| /* |
| * This file implements the perfmon-2 subsystem which is used |
| * to program the IA-64 Performance Monitoring Unit (PMU). |
| * |
| * The initial version of perfmon.c was written by |
| * Ganesh Venkitachalam, IBM Corp. |
| * |
| * Then it was modified for perfmon-1.x by Stephane Eranian and |
| * David Mosberger, Hewlett Packard Co. |
| * |
| * Version Perfmon-2.x is a rewrite of perfmon-1.x |
| * by Stephane Eranian, Hewlett Packard Co. |
| * |
| * Copyright (C) 1999-2005 Hewlett Packard Co |
| * Stephane Eranian <eranian@hpl.hp.com> |
| * David Mosberger-Tang <davidm@hpl.hp.com> |
| * |
| * More information about perfmon available at: |
| * http://www.hpl.hp.com/research/linux/perfmon |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/interrupt.h> |
| #include <linux/smp_lock.h> |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| #include <linux/init.h> |
| #include <linux/vmalloc.h> |
| #include <linux/mm.h> |
| #include <linux/sysctl.h> |
| #include <linux/list.h> |
| #include <linux/file.h> |
| #include <linux/poll.h> |
| #include <linux/vfs.h> |
| #include <linux/pagemap.h> |
| #include <linux/mount.h> |
| #include <linux/bitops.h> |
| #include <linux/rcupdate.h> |
| |
| #include <asm/errno.h> |
| #include <asm/intrinsics.h> |
| #include <asm/page.h> |
| #include <asm/perfmon.h> |
| #include <asm/processor.h> |
| #include <asm/signal.h> |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| #include <asm/delay.h> |
| |
| #ifdef CONFIG_PERFMON |
| /* |
| * perfmon context state |
| */ |
| #define PFM_CTX_UNLOADED 1 /* context is not loaded onto any task */ |
| #define PFM_CTX_LOADED 2 /* context is loaded onto a task */ |
| #define PFM_CTX_MASKED 3 /* context is loaded but monitoring is masked due to overflow */ |
| #define PFM_CTX_ZOMBIE 4 /* owner of the context is closing it */ |
| |
| #define PFM_INVALID_ACTIVATION (~0UL) |
| |
| /* |
| * depth of message queue |
| */ |
| #define PFM_MAX_MSGS 32 |
| #define PFM_CTXQ_EMPTY(g) ((g)->ctx_msgq_head == (g)->ctx_msgq_tail) |
| |
| /* |
| * type of a PMU register (bitmask). |
| * bitmask structure: |
| * bit0 : register implemented |
| * bit1 : end marker |
| * bit2-3 : reserved |
| * bit4 : pmc has pmc.pm |
| * bit5 : pmc controls a counter (has pmc.oi), pmd is used as counter |
| * bit6-7 : register type |
| * bit8-31: reserved |
| */ |
| #define PFM_REG_NOTIMPL 0x0 /* not implemented at all */ |
| #define PFM_REG_IMPL 0x1 /* register implemented */ |
| #define PFM_REG_END 0x2 /* end marker */ |
| #define PFM_REG_MONITOR (0x1<<4|PFM_REG_IMPL) /* a PMC with a pmc.pm field only */ |
| #define PFM_REG_COUNTING (0x2<<4|PFM_REG_MONITOR) /* a monitor + pmc.oi+ PMD used as a counter */ |
| #define PFM_REG_CONTROL (0x4<<4|PFM_REG_IMPL) /* PMU control register */ |
| #define PFM_REG_CONFIG (0x8<<4|PFM_REG_IMPL) /* configuration register */ |
| #define PFM_REG_BUFFER (0xc<<4|PFM_REG_IMPL) /* PMD used as buffer */ |
| |
| #define PMC_IS_LAST(i) (pmu_conf->pmc_desc[i].type & PFM_REG_END) |
| #define PMD_IS_LAST(i) (pmu_conf->pmd_desc[i].type & PFM_REG_END) |
| |
| #define PMC_OVFL_NOTIFY(ctx, i) ((ctx)->ctx_pmds[i].flags & PFM_REGFL_OVFL_NOTIFY) |
| |
| /* i assumed unsigned */ |
| #define PMC_IS_IMPL(i) (i< PMU_MAX_PMCS && (pmu_conf->pmc_desc[i].type & PFM_REG_IMPL)) |
| #define PMD_IS_IMPL(i) (i< PMU_MAX_PMDS && (pmu_conf->pmd_desc[i].type & PFM_REG_IMPL)) |
| |
| /* XXX: these assume that register i is implemented */ |
| #define PMD_IS_COUNTING(i) ((pmu_conf->pmd_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING) |
| #define PMC_IS_COUNTING(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_COUNTING) == PFM_REG_COUNTING) |
| #define PMC_IS_MONITOR(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_MONITOR) == PFM_REG_MONITOR) |
| #define PMC_IS_CONTROL(i) ((pmu_conf->pmc_desc[i].type & PFM_REG_CONTROL) == PFM_REG_CONTROL) |
| |
| #define PMC_DFL_VAL(i) pmu_conf->pmc_desc[i].default_value |
| #define PMC_RSVD_MASK(i) pmu_conf->pmc_desc[i].reserved_mask |
| #define PMD_PMD_DEP(i) pmu_conf->pmd_desc[i].dep_pmd[0] |
| #define PMC_PMD_DEP(i) pmu_conf->pmc_desc[i].dep_pmd[0] |
| |
| #define PFM_NUM_IBRS IA64_NUM_DBG_REGS |
| #define PFM_NUM_DBRS IA64_NUM_DBG_REGS |
| |
| #define CTX_OVFL_NOBLOCK(c) ((c)->ctx_fl_block == 0) |
| #define CTX_HAS_SMPL(c) ((c)->ctx_fl_is_sampling) |
| #define PFM_CTX_TASK(h) (h)->ctx_task |
| |
| #define PMU_PMC_OI 5 /* position of pmc.oi bit */ |
| |
| /* XXX: does not support more than 64 PMDs */ |
| #define CTX_USED_PMD(ctx, mask) (ctx)->ctx_used_pmds[0] |= (mask) |
| #define CTX_IS_USED_PMD(ctx, c) (((ctx)->ctx_used_pmds[0] & (1UL << (c))) != 0UL) |
| |
| #define CTX_USED_MONITOR(ctx, mask) (ctx)->ctx_used_monitors[0] |= (mask) |
| |
| #define CTX_USED_IBR(ctx,n) (ctx)->ctx_used_ibrs[(n)>>6] |= 1UL<< ((n) % 64) |
| #define CTX_USED_DBR(ctx,n) (ctx)->ctx_used_dbrs[(n)>>6] |= 1UL<< ((n) % 64) |
| #define CTX_USES_DBREGS(ctx) (((pfm_context_t *)(ctx))->ctx_fl_using_dbreg==1) |
| #define PFM_CODE_RR 0 /* requesting code range restriction */ |
| #define PFM_DATA_RR 1 /* requestion data range restriction */ |
| |
| #define PFM_CPUINFO_CLEAR(v) pfm_get_cpu_var(pfm_syst_info) &= ~(v) |
| #define PFM_CPUINFO_SET(v) pfm_get_cpu_var(pfm_syst_info) |= (v) |
| #define PFM_CPUINFO_GET() pfm_get_cpu_var(pfm_syst_info) |
| |
| #define RDEP(x) (1UL<<(x)) |
| |
| /* |
| * context protection macros |
| * in SMP: |
| * - we need to protect against CPU concurrency (spin_lock) |
| * - we need to protect against PMU overflow interrupts (local_irq_disable) |
| * in UP: |
| * - we need to protect against PMU overflow interrupts (local_irq_disable) |
| * |
| * spin_lock_irqsave()/spin_lock_irqrestore(): |
| * in SMP: local_irq_disable + spin_lock |
| * in UP : local_irq_disable |
| * |
| * spin_lock()/spin_lock(): |
| * in UP : removed automatically |
| * in SMP: protect against context accesses from other CPU. interrupts |
| * are not masked. This is useful for the PMU interrupt handler |
| * because we know we will not get PMU concurrency in that code. |
| */ |
| #define PROTECT_CTX(c, f) \ |
| do { \ |
| DPRINT(("spinlock_irq_save ctx %p by [%d]\n", c, current->pid)); \ |
| spin_lock_irqsave(&(c)->ctx_lock, f); \ |
| DPRINT(("spinlocked ctx %p by [%d]\n", c, current->pid)); \ |
| } while(0) |
| |
| #define UNPROTECT_CTX(c, f) \ |
| do { \ |
| DPRINT(("spinlock_irq_restore ctx %p by [%d]\n", c, current->pid)); \ |
| spin_unlock_irqrestore(&(c)->ctx_lock, f); \ |
| } while(0) |
| |
| #define PROTECT_CTX_NOPRINT(c, f) \ |
| do { \ |
| spin_lock_irqsave(&(c)->ctx_lock, f); \ |
| } while(0) |
| |
| |
| #define UNPROTECT_CTX_NOPRINT(c, f) \ |
| do { \ |
| spin_unlock_irqrestore(&(c)->ctx_lock, f); \ |
| } while(0) |
| |
| |
| #define PROTECT_CTX_NOIRQ(c) \ |
| do { \ |
| spin_lock(&(c)->ctx_lock); \ |
| } while(0) |
| |
| #define UNPROTECT_CTX_NOIRQ(c) \ |
| do { \ |
| spin_unlock(&(c)->ctx_lock); \ |
| } while(0) |
| |
| |
| #ifdef CONFIG_SMP |
| |
| #define GET_ACTIVATION() pfm_get_cpu_var(pmu_activation_number) |
| #define INC_ACTIVATION() pfm_get_cpu_var(pmu_activation_number)++ |
| #define SET_ACTIVATION(c) (c)->ctx_last_activation = GET_ACTIVATION() |
| |
| #else /* !CONFIG_SMP */ |
| #define SET_ACTIVATION(t) do {} while(0) |
| #define GET_ACTIVATION(t) do {} while(0) |
| #define INC_ACTIVATION(t) do {} while(0) |
| #endif /* CONFIG_SMP */ |
| |
| #define SET_PMU_OWNER(t, c) do { pfm_get_cpu_var(pmu_owner) = (t); pfm_get_cpu_var(pmu_ctx) = (c); } while(0) |
| #define GET_PMU_OWNER() pfm_get_cpu_var(pmu_owner) |
| #define GET_PMU_CTX() pfm_get_cpu_var(pmu_ctx) |
| |
| #define LOCK_PFS(g) spin_lock_irqsave(&pfm_sessions.pfs_lock, g) |
| #define UNLOCK_PFS(g) spin_unlock_irqrestore(&pfm_sessions.pfs_lock, g) |
| |
| #define PFM_REG_RETFLAG_SET(flags, val) do { flags &= ~PFM_REG_RETFL_MASK; flags |= (val); } while(0) |
| |
| /* |
| * cmp0 must be the value of pmc0 |
| */ |
| #define PMC0_HAS_OVFL(cmp0) (cmp0 & ~0x1UL) |
| |
| #define PFMFS_MAGIC 0xa0b4d889 |
| |
| /* |
| * debugging |
| */ |
| #define PFM_DEBUGGING 1 |
| #ifdef PFM_DEBUGGING |
| #define DPRINT(a) \ |
| do { \ |
| if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \ |
| } while (0) |
| |
| #define DPRINT_ovfl(a) \ |
| do { \ |
| if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d [%d] ", __FUNCTION__, __LINE__, smp_processor_id(), current->pid); printk a; } \ |
| } while (0) |
| #endif |
| |
| /* |
| * 64-bit software counter structure |
| * |
| * the next_reset_type is applied to the next call to pfm_reset_regs() |
| */ |
| typedef struct { |
| unsigned long val; /* virtual 64bit counter value */ |
| unsigned long lval; /* last reset value */ |
| unsigned long long_reset; /* reset value on sampling overflow */ |
| unsigned long short_reset; /* reset value on overflow */ |
| unsigned long reset_pmds[4]; /* which other pmds to reset when this counter overflows */ |
| unsigned long smpl_pmds[4]; /* which pmds are accessed when counter overflow */ |
| unsigned long seed; /* seed for random-number generator */ |
| unsigned long mask; /* mask for random-number generator */ |
| unsigned int flags; /* notify/do not notify */ |
| unsigned long eventid; /* overflow event identifier */ |
| } pfm_counter_t; |
| |
| /* |
| * context flags |
| */ |
| typedef struct { |
| unsigned int block:1; /* when 1, task will blocked on user notifications */ |
| unsigned int system:1; /* do system wide monitoring */ |
| unsigned int using_dbreg:1; /* using range restrictions (debug registers) */ |
| unsigned int is_sampling:1; /* true if using a custom format */ |
| unsigned int excl_idle:1; /* exclude idle task in system wide session */ |
| unsigned int going_zombie:1; /* context is zombie (MASKED+blocking) */ |
| unsigned int trap_reason:2; /* reason for going into pfm_handle_work() */ |
| unsigned int no_msg:1; /* no message sent on overflow */ |
| unsigned int can_restart:1; /* allowed to issue a PFM_RESTART */ |
| unsigned int reserved:22; |
| } pfm_context_flags_t; |
| |
| #define PFM_TRAP_REASON_NONE 0x0 /* default value */ |
| #define PFM_TRAP_REASON_BLOCK 0x1 /* we need to block on overflow */ |
| #define PFM_TRAP_REASON_RESET 0x2 /* we need to reset PMDs */ |
| |
| |
| /* |
| * perfmon context: encapsulates all the state of a monitoring session |
| */ |
| |
| typedef struct pfm_context { |
| spinlock_t ctx_lock; /* context protection */ |
| |
| pfm_context_flags_t ctx_flags; /* bitmask of flags (block reason incl.) */ |
| unsigned int ctx_state; /* state: active/inactive (no bitfield) */ |
| |
| struct task_struct *ctx_task; /* task to which context is attached */ |
| |
| unsigned long ctx_ovfl_regs[4]; /* which registers overflowed (notification) */ |
| |
| struct semaphore ctx_restart_sem; /* use for blocking notification mode */ |
| |
| unsigned long ctx_used_pmds[4]; /* bitmask of PMD used */ |
| unsigned long ctx_all_pmds[4]; /* bitmask of all accessible PMDs */ |
| unsigned long ctx_reload_pmds[4]; /* bitmask of force reload PMD on ctxsw in */ |
| |
| unsigned long ctx_all_pmcs[4]; /* bitmask of all accessible PMCs */ |
| unsigned long ctx_reload_pmcs[4]; /* bitmask of force reload PMC on ctxsw in */ |
| unsigned long ctx_used_monitors[4]; /* bitmask of monitor PMC being used */ |
| |
| unsigned long ctx_pmcs[IA64_NUM_PMC_REGS]; /* saved copies of PMC values */ |
| |
| unsigned int ctx_used_ibrs[1]; /* bitmask of used IBR (speedup ctxsw in) */ |
| unsigned int ctx_used_dbrs[1]; /* bitmask of used DBR (speedup ctxsw in) */ |
| unsigned long ctx_dbrs[IA64_NUM_DBG_REGS]; /* DBR values (cache) when not loaded */ |
| unsigned long ctx_ibrs[IA64_NUM_DBG_REGS]; /* IBR values (cache) when not loaded */ |
| |
| pfm_counter_t ctx_pmds[IA64_NUM_PMD_REGS]; /* software state for PMDS */ |
| |
| u64 ctx_saved_psr_up; /* only contains psr.up value */ |
| |
| unsigned long ctx_last_activation; /* context last activation number for last_cpu */ |
| unsigned int ctx_last_cpu; /* CPU id of current or last CPU used (SMP only) */ |
| unsigned int ctx_cpu; /* cpu to which perfmon is applied (system wide) */ |
| |
| int ctx_fd; /* file descriptor used my this context */ |
| pfm_ovfl_arg_t ctx_ovfl_arg; /* argument to custom buffer format handler */ |
| |
| pfm_buffer_fmt_t *ctx_buf_fmt; /* buffer format callbacks */ |
| void *ctx_smpl_hdr; /* points to sampling buffer header kernel vaddr */ |
| unsigned long ctx_smpl_size; /* size of sampling buffer */ |
| void *ctx_smpl_vaddr; /* user level virtual address of smpl buffer */ |
| |
| wait_queue_head_t ctx_msgq_wait; |
| pfm_msg_t ctx_msgq[PFM_MAX_MSGS]; |
| int ctx_msgq_head; |
| int ctx_msgq_tail; |
| struct fasync_struct *ctx_async_queue; |
| |
| wait_queue_head_t ctx_zombieq; /* termination cleanup wait queue */ |
| } pfm_context_t; |
| |
| /* |
| * magic number used to verify that structure is really |
| * a perfmon context |
| */ |
| #define PFM_IS_FILE(f) ((f)->f_op == &pfm_file_ops) |
| |
| #define PFM_GET_CTX(t) ((pfm_context_t *)(t)->thread.pfm_context) |
| |
| #ifdef CONFIG_SMP |
| #define SET_LAST_CPU(ctx, v) (ctx)->ctx_last_cpu = (v) |
| #define GET_LAST_CPU(ctx) (ctx)->ctx_last_cpu |
| #else |
| #define SET_LAST_CPU(ctx, v) do {} while(0) |
| #define GET_LAST_CPU(ctx) do {} while(0) |
| #endif |
| |
| |
| #define ctx_fl_block ctx_flags.block |
| #define ctx_fl_system ctx_flags.system |
| #define ctx_fl_using_dbreg ctx_flags.using_dbreg |
| #define ctx_fl_is_sampling ctx_flags.is_sampling |
| #define ctx_fl_excl_idle ctx_flags.excl_idle |
| #define ctx_fl_going_zombie ctx_flags.going_zombie |
| #define ctx_fl_trap_reason ctx_flags.trap_reason |
| #define ctx_fl_no_msg ctx_flags.no_msg |
| #define ctx_fl_can_restart ctx_flags.can_restart |
| |
| #define PFM_SET_WORK_PENDING(t, v) do { (t)->thread.pfm_needs_checking = v; } while(0); |
| #define PFM_GET_WORK_PENDING(t) (t)->thread.pfm_needs_checking |
| |
| /* |
| * global information about all sessions |
| * mostly used to synchronize between system wide and per-process |
| */ |
| typedef struct { |
| spinlock_t pfs_lock; /* lock the structure */ |
| |
| unsigned int pfs_task_sessions; /* number of per task sessions */ |
| unsigned int pfs_sys_sessions; /* number of per system wide sessions */ |
| unsigned int pfs_sys_use_dbregs; /* incremented when a system wide session uses debug regs */ |
| unsigned int pfs_ptrace_use_dbregs; /* incremented when a process uses debug regs */ |
| struct task_struct *pfs_sys_session[NR_CPUS]; /* point to task owning a system-wide session */ |
| } pfm_session_t; |
| |
| /* |
| * information about a PMC or PMD. |
| * dep_pmd[]: a bitmask of dependent PMD registers |
| * dep_pmc[]: a bitmask of dependent PMC registers |
| */ |
| typedef int (*pfm_reg_check_t)(struct task_struct *task, pfm_context_t *ctx, unsigned int cnum, unsigned long *val, struct pt_regs *regs); |
| typedef struct { |
| unsigned int type; |
| int pm_pos; |
| unsigned long default_value; /* power-on default value */ |
| unsigned long reserved_mask; /* bitmask of reserved bits */ |
| pfm_reg_check_t read_check; |
| pfm_reg_check_t write_check; |
| unsigned long dep_pmd[4]; |
| unsigned long dep_pmc[4]; |
| } pfm_reg_desc_t; |
| |
| /* assume cnum is a valid monitor */ |
| #define PMC_PM(cnum, val) (((val) >> (pmu_conf->pmc_desc[cnum].pm_pos)) & 0x1) |
| |
| /* |
| * This structure is initialized at boot time and contains |
| * a description of the PMU main characteristics. |
| * |
| * If the probe function is defined, detection is based |
| * on its return value: |
| * - 0 means recognized PMU |
| * - anything else means not supported |
| * When the probe function is not defined, then the pmu_family field |
| * is used and it must match the host CPU family such that: |
| * - cpu->family & config->pmu_family != 0 |
| */ |
| typedef struct { |
| unsigned long ovfl_val; /* overflow value for counters */ |
| |
| pfm_reg_desc_t *pmc_desc; /* detailed PMC register dependencies descriptions */ |
| pfm_reg_desc_t *pmd_desc; /* detailed PMD register dependencies descriptions */ |
| |
| unsigned int num_pmcs; /* number of PMCS: computed at init time */ |
| unsigned int num_pmds; /* number of PMDS: computed at init time */ |
| unsigned long impl_pmcs[4]; /* bitmask of implemented PMCS */ |
| unsigned long impl_pmds[4]; /* bitmask of implemented PMDS */ |
| |
| char *pmu_name; /* PMU family name */ |
| unsigned int pmu_family; /* cpuid family pattern used to identify pmu */ |
| unsigned int flags; /* pmu specific flags */ |
| unsigned int num_ibrs; /* number of IBRS: computed at init time */ |
| unsigned int num_dbrs; /* number of DBRS: computed at init time */ |
| unsigned int num_counters; /* PMC/PMD counting pairs : computed at init time */ |
| int (*probe)(void); /* customized probe routine */ |
| unsigned int use_rr_dbregs:1; /* set if debug registers used for range restriction */ |
| } pmu_config_t; |
| /* |
| * PMU specific flags |
| */ |
| #define PFM_PMU_IRQ_RESEND 1 /* PMU needs explicit IRQ resend */ |
| |
| /* |
| * debug register related type definitions |
| */ |
| typedef struct { |
| unsigned long ibr_mask:56; |
| unsigned long ibr_plm:4; |
| unsigned long ibr_ig:3; |
| unsigned long ibr_x:1; |
| } ibr_mask_reg_t; |
| |
| typedef struct { |
| unsigned long dbr_mask:56; |
| unsigned long dbr_plm:4; |
| unsigned long dbr_ig:2; |
| unsigned long dbr_w:1; |
| unsigned long dbr_r:1; |
| } dbr_mask_reg_t; |
| |
| typedef union { |
| unsigned long val; |
| ibr_mask_reg_t ibr; |
| dbr_mask_reg_t dbr; |
| } dbreg_t; |
| |
| |
| /* |
| * perfmon command descriptions |
| */ |
| typedef struct { |
| int (*cmd_func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); |
| char *cmd_name; |
| int cmd_flags; |
| unsigned int cmd_narg; |
| size_t cmd_argsize; |
| int (*cmd_getsize)(void *arg, size_t *sz); |
| } pfm_cmd_desc_t; |
| |
| #define PFM_CMD_FD 0x01 /* command requires a file descriptor */ |
| #define PFM_CMD_ARG_READ 0x02 /* command must read argument(s) */ |
| #define PFM_CMD_ARG_RW 0x04 /* command must read/write argument(s) */ |
| #define PFM_CMD_STOP 0x08 /* command does not work on zombie context */ |
| |
| |
| #define PFM_CMD_NAME(cmd) pfm_cmd_tab[(cmd)].cmd_name |
| #define PFM_CMD_READ_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_READ) |
| #define PFM_CMD_RW_ARG(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_ARG_RW) |
| #define PFM_CMD_USE_FD(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_FD) |
| #define PFM_CMD_STOPPED(cmd) (pfm_cmd_tab[(cmd)].cmd_flags & PFM_CMD_STOP) |
| |
| #define PFM_CMD_ARG_MANY -1 /* cannot be zero */ |
| |
| typedef struct { |
| unsigned long pfm_spurious_ovfl_intr_count; /* keep track of spurious ovfl interrupts */ |
| unsigned long pfm_replay_ovfl_intr_count; /* keep track of replayed ovfl interrupts */ |
| unsigned long pfm_ovfl_intr_count; /* keep track of ovfl interrupts */ |
| unsigned long pfm_ovfl_intr_cycles; /* cycles spent processing ovfl interrupts */ |
| unsigned long pfm_ovfl_intr_cycles_min; /* min cycles spent processing ovfl interrupts */ |
| unsigned long pfm_ovfl_intr_cycles_max; /* max cycles spent processing ovfl interrupts */ |
| unsigned long pfm_smpl_handler_calls; |
| unsigned long pfm_smpl_handler_cycles; |
| char pad[SMP_CACHE_BYTES] ____cacheline_aligned; |
| } pfm_stats_t; |
| |
| /* |
| * perfmon internal variables |
| */ |
| static pfm_stats_t pfm_stats[NR_CPUS]; |
| static pfm_session_t pfm_sessions; /* global sessions information */ |
| |
| static spinlock_t pfm_alt_install_check = SPIN_LOCK_UNLOCKED; |
| static pfm_intr_handler_desc_t *pfm_alt_intr_handler; |
| |
| static struct proc_dir_entry *perfmon_dir; |
| static pfm_uuid_t pfm_null_uuid = {0,}; |
| |
| static spinlock_t pfm_buffer_fmt_lock; |
| static LIST_HEAD(pfm_buffer_fmt_list); |
| |
| static pmu_config_t *pmu_conf; |
| |
| /* sysctl() controls */ |
| pfm_sysctl_t pfm_sysctl; |
| EXPORT_SYMBOL(pfm_sysctl); |
| |
| static ctl_table pfm_ctl_table[]={ |
| {1, "debug", &pfm_sysctl.debug, sizeof(int), 0666, NULL, &proc_dointvec, NULL,}, |
| {2, "debug_ovfl", &pfm_sysctl.debug_ovfl, sizeof(int), 0666, NULL, &proc_dointvec, NULL,}, |
| {3, "fastctxsw", &pfm_sysctl.fastctxsw, sizeof(int), 0600, NULL, &proc_dointvec, NULL,}, |
| {4, "expert_mode", &pfm_sysctl.expert_mode, sizeof(int), 0600, NULL, &proc_dointvec, NULL,}, |
| { 0, }, |
| }; |
| static ctl_table pfm_sysctl_dir[] = { |
| {1, "perfmon", NULL, 0, 0755, pfm_ctl_table, }, |
| {0,}, |
| }; |
| static ctl_table pfm_sysctl_root[] = { |
| {1, "kernel", NULL, 0, 0755, pfm_sysctl_dir, }, |
| {0,}, |
| }; |
| static struct ctl_table_header *pfm_sysctl_header; |
| |
| static int pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); |
| static int pfm_flush(struct file *filp); |
| |
| #define pfm_get_cpu_var(v) __ia64_per_cpu_var(v) |
| #define pfm_get_cpu_data(a,b) per_cpu(a, b) |
| |
| static inline void |
| pfm_put_task(struct task_struct *task) |
| { |
| if (task != current) put_task_struct(task); |
| } |
| |
| static inline void |
| pfm_set_task_notify(struct task_struct *task) |
| { |
| struct thread_info *info; |
| |
| info = (struct thread_info *) ((char *) task + IA64_TASK_SIZE); |
| set_bit(TIF_NOTIFY_RESUME, &info->flags); |
| } |
| |
| static inline void |
| pfm_clear_task_notify(void) |
| { |
| clear_thread_flag(TIF_NOTIFY_RESUME); |
| } |
| |
| static inline void |
| pfm_reserve_page(unsigned long a) |
| { |
| SetPageReserved(vmalloc_to_page((void *)a)); |
| } |
| static inline void |
| pfm_unreserve_page(unsigned long a) |
| { |
| ClearPageReserved(vmalloc_to_page((void*)a)); |
| } |
| |
| static inline unsigned long |
| pfm_protect_ctx_ctxsw(pfm_context_t *x) |
| { |
| spin_lock(&(x)->ctx_lock); |
| return 0UL; |
| } |
| |
| static inline unsigned long |
| pfm_unprotect_ctx_ctxsw(pfm_context_t *x, unsigned long f) |
| { |
| spin_unlock(&(x)->ctx_lock); |
| } |
| |
| static inline unsigned int |
| pfm_do_munmap(struct mm_struct *mm, unsigned long addr, size_t len, int acct) |
| { |
| return do_munmap(mm, addr, len); |
| } |
| |
| static inline unsigned long |
| pfm_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, unsigned long exec) |
| { |
| return get_unmapped_area(file, addr, len, pgoff, flags); |
| } |
| |
| |
| static struct super_block * |
| pfmfs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) |
| { |
| return get_sb_pseudo(fs_type, "pfm:", NULL, PFMFS_MAGIC); |
| } |
| |
| static struct file_system_type pfm_fs_type = { |
| .name = "pfmfs", |
| .get_sb = pfmfs_get_sb, |
| .kill_sb = kill_anon_super, |
| }; |
| |
| DEFINE_PER_CPU(unsigned long, pfm_syst_info); |
| DEFINE_PER_CPU(struct task_struct *, pmu_owner); |
| DEFINE_PER_CPU(pfm_context_t *, pmu_ctx); |
| DEFINE_PER_CPU(unsigned long, pmu_activation_number); |
| EXPORT_PER_CPU_SYMBOL_GPL(pfm_syst_info); |
| |
| |
| /* forward declaration */ |
| static struct file_operations pfm_file_ops; |
| |
| /* |
| * forward declarations |
| */ |
| #ifndef CONFIG_SMP |
| static void pfm_lazy_save_regs (struct task_struct *ta); |
| #endif |
| |
| void dump_pmu_state(const char *); |
| static int pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); |
| |
| #include "perfmon_itanium.h" |
| #include "perfmon_mckinley.h" |
| #include "perfmon_generic.h" |
| |
| static pmu_config_t *pmu_confs[]={ |
| &pmu_conf_mck, |
| &pmu_conf_ita, |
| &pmu_conf_gen, /* must be last */ |
| NULL |
| }; |
| |
| |
| static int pfm_end_notify_user(pfm_context_t *ctx); |
| |
| static inline void |
| pfm_clear_psr_pp(void) |
| { |
| ia64_rsm(IA64_PSR_PP); |
| ia64_srlz_i(); |
| } |
| |
| static inline void |
| pfm_set_psr_pp(void) |
| { |
| ia64_ssm(IA64_PSR_PP); |
| ia64_srlz_i(); |
| } |
| |
| static inline void |
| pfm_clear_psr_up(void) |
| { |
| ia64_rsm(IA64_PSR_UP); |
| ia64_srlz_i(); |
| } |
| |
| static inline void |
| pfm_set_psr_up(void) |
| { |
| ia64_ssm(IA64_PSR_UP); |
| ia64_srlz_i(); |
| } |
| |
| static inline unsigned long |
| pfm_get_psr(void) |
| { |
| unsigned long tmp; |
| tmp = ia64_getreg(_IA64_REG_PSR); |
| ia64_srlz_i(); |
| return tmp; |
| } |
| |
| static inline void |
| pfm_set_psr_l(unsigned long val) |
| { |
| ia64_setreg(_IA64_REG_PSR_L, val); |
| ia64_srlz_i(); |
| } |
| |
| static inline void |
| pfm_freeze_pmu(void) |
| { |
| ia64_set_pmc(0,1UL); |
| ia64_srlz_d(); |
| } |
| |
| static inline void |
| pfm_unfreeze_pmu(void) |
| { |
| ia64_set_pmc(0,0UL); |
| ia64_srlz_d(); |
| } |
| |
| static inline void |
| pfm_restore_ibrs(unsigned long *ibrs, unsigned int nibrs) |
| { |
| int i; |
| |
| for (i=0; i < nibrs; i++) { |
| ia64_set_ibr(i, ibrs[i]); |
| ia64_dv_serialize_instruction(); |
| } |
| ia64_srlz_i(); |
| } |
| |
| static inline void |
| pfm_restore_dbrs(unsigned long *dbrs, unsigned int ndbrs) |
| { |
| int i; |
| |
| for (i=0; i < ndbrs; i++) { |
| ia64_set_dbr(i, dbrs[i]); |
| ia64_dv_serialize_data(); |
| } |
| ia64_srlz_d(); |
| } |
| |
| /* |
| * PMD[i] must be a counter. no check is made |
| */ |
| static inline unsigned long |
| pfm_read_soft_counter(pfm_context_t *ctx, int i) |
| { |
| return ctx->ctx_pmds[i].val + (ia64_get_pmd(i) & pmu_conf->ovfl_val); |
| } |
| |
| /* |
| * PMD[i] must be a counter. no check is made |
| */ |
| static inline void |
| pfm_write_soft_counter(pfm_context_t *ctx, int i, unsigned long val) |
| { |
| unsigned long ovfl_val = pmu_conf->ovfl_val; |
| |
| ctx->ctx_pmds[i].val = val & ~ovfl_val; |
| /* |
| * writing to unimplemented part is ignore, so we do not need to |
| * mask off top part |
| */ |
| ia64_set_pmd(i, val & ovfl_val); |
| } |
| |
| static pfm_msg_t * |
| pfm_get_new_msg(pfm_context_t *ctx) |
| { |
| int idx, next; |
| |
| next = (ctx->ctx_msgq_tail+1) % PFM_MAX_MSGS; |
| |
| DPRINT(("ctx_fd=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); |
| if (next == ctx->ctx_msgq_head) return NULL; |
| |
| idx = ctx->ctx_msgq_tail; |
| ctx->ctx_msgq_tail = next; |
| |
| DPRINT(("ctx=%p head=%d tail=%d msg=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, idx)); |
| |
| return ctx->ctx_msgq+idx; |
| } |
| |
| static pfm_msg_t * |
| pfm_get_next_msg(pfm_context_t *ctx) |
| { |
| pfm_msg_t *msg; |
| |
| DPRINT(("ctx=%p head=%d tail=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); |
| |
| if (PFM_CTXQ_EMPTY(ctx)) return NULL; |
| |
| /* |
| * get oldest message |
| */ |
| msg = ctx->ctx_msgq+ctx->ctx_msgq_head; |
| |
| /* |
| * and move forward |
| */ |
| ctx->ctx_msgq_head = (ctx->ctx_msgq_head+1) % PFM_MAX_MSGS; |
| |
| DPRINT(("ctx=%p head=%d tail=%d type=%d\n", ctx, ctx->ctx_msgq_head, ctx->ctx_msgq_tail, msg->pfm_gen_msg.msg_type)); |
| |
| return msg; |
| } |
| |
| static void |
| pfm_reset_msgq(pfm_context_t *ctx) |
| { |
| ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0; |
| DPRINT(("ctx=%p msgq reset\n", ctx)); |
| } |
| |
| static void * |
| pfm_rvmalloc(unsigned long size) |
| { |
| void *mem; |
| unsigned long addr; |
| |
| size = PAGE_ALIGN(size); |
| mem = vmalloc(size); |
| if (mem) { |
| //printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem); |
| memset(mem, 0, size); |
| addr = (unsigned long)mem; |
| while (size > 0) { |
| pfm_reserve_page(addr); |
| addr+=PAGE_SIZE; |
| size-=PAGE_SIZE; |
| } |
| } |
| return mem; |
| } |
| |
| static void |
| pfm_rvfree(void *mem, unsigned long size) |
| { |
| unsigned long addr; |
| |
| if (mem) { |
| DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size)); |
| addr = (unsigned long) mem; |
| while ((long) size > 0) { |
| pfm_unreserve_page(addr); |
| addr+=PAGE_SIZE; |
| size-=PAGE_SIZE; |
| } |
| vfree(mem); |
| } |
| return; |
| } |
| |
| static pfm_context_t * |
| pfm_context_alloc(void) |
| { |
| pfm_context_t *ctx; |
| |
| /* |
| * allocate context descriptor |
| * must be able to free with interrupts disabled |
| */ |
| ctx = kmalloc(sizeof(pfm_context_t), GFP_KERNEL); |
| if (ctx) { |
| memset(ctx, 0, sizeof(pfm_context_t)); |
| DPRINT(("alloc ctx @%p\n", ctx)); |
| } |
| return ctx; |
| } |
| |
| static void |
| pfm_context_free(pfm_context_t *ctx) |
| { |
| if (ctx) { |
| DPRINT(("free ctx @%p\n", ctx)); |
| kfree(ctx); |
| } |
| } |
| |
| static void |
| pfm_mask_monitoring(struct task_struct *task) |
| { |
| pfm_context_t *ctx = PFM_GET_CTX(task); |
| struct thread_struct *th = &task->thread; |
| unsigned long mask, val, ovfl_mask; |
| int i; |
| |
| DPRINT_ovfl(("masking monitoring for [%d]\n", task->pid)); |
| |
| ovfl_mask = pmu_conf->ovfl_val; |
| /* |
| * monitoring can only be masked as a result of a valid |
| * counter overflow. In UP, it means that the PMU still |
| * has an owner. Note that the owner can be different |
| * from the current task. However the PMU state belongs |
| * to the owner. |
| * In SMP, a valid overflow only happens when task is |
| * current. Therefore if we come here, we know that |
| * the PMU state belongs to the current task, therefore |
| * we can access the live registers. |
| * |
| * So in both cases, the live register contains the owner's |
| * state. We can ONLY touch the PMU registers and NOT the PSR. |
| * |
| * As a consequence to this call, the thread->pmds[] array |
| * contains stale information which must be ignored |
| * when context is reloaded AND monitoring is active (see |
| * pfm_restart). |
| */ |
| mask = ctx->ctx_used_pmds[0]; |
| for (i = 0; mask; i++, mask>>=1) { |
| /* skip non used pmds */ |
| if ((mask & 0x1) == 0) continue; |
| val = ia64_get_pmd(i); |
| |
| if (PMD_IS_COUNTING(i)) { |
| /* |
| * we rebuild the full 64 bit value of the counter |
| */ |
| ctx->ctx_pmds[i].val += (val & ovfl_mask); |
| } else { |
| ctx->ctx_pmds[i].val = val; |
| } |
| DPRINT_ovfl(("pmd[%d]=0x%lx hw_pmd=0x%lx\n", |
| i, |
| ctx->ctx_pmds[i].val, |
| val & ovfl_mask)); |
| } |
| /* |
| * mask monitoring by setting the privilege level to 0 |
| * we cannot use psr.pp/psr.up for this, it is controlled by |
| * the user |
| * |
| * if task is current, modify actual registers, otherwise modify |
| * thread save state, i.e., what will be restored in pfm_load_regs() |
| */ |
| mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER; |
| for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) { |
| if ((mask & 0x1) == 0UL) continue; |
| ia64_set_pmc(i, th->pmcs[i] & ~0xfUL); |
| th->pmcs[i] &= ~0xfUL; |
| DPRINT_ovfl(("pmc[%d]=0x%lx\n", i, th->pmcs[i])); |
| } |
| /* |
| * make all of this visible |
| */ |
| ia64_srlz_d(); |
| } |
| |
| /* |
| * must always be done with task == current |
| * |
| * context must be in MASKED state when calling |
| */ |
| static void |
| pfm_restore_monitoring(struct task_struct *task) |
| { |
| pfm_context_t *ctx = PFM_GET_CTX(task); |
| struct thread_struct *th = &task->thread; |
| unsigned long mask, ovfl_mask; |
| unsigned long psr, val; |
| int i, is_system; |
| |
| is_system = ctx->ctx_fl_system; |
| ovfl_mask = pmu_conf->ovfl_val; |
| |
| if (task != current) { |
| printk(KERN_ERR "perfmon.%d: invalid task[%d] current[%d]\n", __LINE__, task->pid, current->pid); |
| return; |
| } |
| if (ctx->ctx_state != PFM_CTX_MASKED) { |
| printk(KERN_ERR "perfmon.%d: task[%d] current[%d] invalid state=%d\n", __LINE__, |
| task->pid, current->pid, ctx->ctx_state); |
| return; |
| } |
| psr = pfm_get_psr(); |
| /* |
| * monitoring is masked via the PMC. |
| * As we restore their value, we do not want each counter to |
| * restart right away. We stop monitoring using the PSR, |
| * restore the PMC (and PMD) and then re-establish the psr |
| * as it was. Note that there can be no pending overflow at |
| * this point, because monitoring was MASKED. |
| * |
| * system-wide session are pinned and self-monitoring |
| */ |
| if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) { |
| /* disable dcr pp */ |
| ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP); |
| pfm_clear_psr_pp(); |
| } else { |
| pfm_clear_psr_up(); |
| } |
| /* |
| * first, we restore the PMD |
| */ |
| mask = ctx->ctx_used_pmds[0]; |
| for (i = 0; mask; i++, mask>>=1) { |
| /* skip non used pmds */ |
| if ((mask & 0x1) == 0) continue; |
| |
| if (PMD_IS_COUNTING(i)) { |
| /* |
| * we split the 64bit value according to |
| * counter width |
| */ |
| val = ctx->ctx_pmds[i].val & ovfl_mask; |
| ctx->ctx_pmds[i].val &= ~ovfl_mask; |
| } else { |
| val = ctx->ctx_pmds[i].val; |
| } |
| ia64_set_pmd(i, val); |
| |
| DPRINT(("pmd[%d]=0x%lx hw_pmd=0x%lx\n", |
| i, |
| ctx->ctx_pmds[i].val, |
| val)); |
| } |
| /* |
| * restore the PMCs |
| */ |
| mask = ctx->ctx_used_monitors[0] >> PMU_FIRST_COUNTER; |
| for(i= PMU_FIRST_COUNTER; mask; i++, mask>>=1) { |
| if ((mask & 0x1) == 0UL) continue; |
| th->pmcs[i] = ctx->ctx_pmcs[i]; |
| ia64_set_pmc(i, th->pmcs[i]); |
| DPRINT(("[%d] pmc[%d]=0x%lx\n", task->pid, i, th->pmcs[i])); |
| } |
| ia64_srlz_d(); |
| |
| /* |
| * must restore DBR/IBR because could be modified while masked |
| * XXX: need to optimize |
| */ |
| if (ctx->ctx_fl_using_dbreg) { |
| pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); |
| pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); |
| } |
| |
| /* |
| * now restore PSR |
| */ |
| if (is_system && (PFM_CPUINFO_GET() & PFM_CPUINFO_DCR_PP)) { |
| /* enable dcr pp */ |
| ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP); |
| ia64_srlz_i(); |
| } |
| pfm_set_psr_l(psr); |
| } |
| |
| static inline void |
| pfm_save_pmds(unsigned long *pmds, unsigned long mask) |
| { |
| int i; |
| |
| ia64_srlz_d(); |
| |
| for (i=0; mask; i++, mask>>=1) { |
| if (mask & 0x1) pmds[i] = ia64_get_pmd(i); |
| } |
| } |
| |
| /* |
| * reload from thread state (used for ctxw only) |
| */ |
| static inline void |
| pfm_restore_pmds(unsigned long *pmds, unsigned long mask) |
| { |
| int i; |
| unsigned long val, ovfl_val = pmu_conf->ovfl_val; |
| |
| for (i=0; mask; i++, mask>>=1) { |
| if ((mask & 0x1) == 0) continue; |
| val = PMD_IS_COUNTING(i) ? pmds[i] & ovfl_val : pmds[i]; |
| ia64_set_pmd(i, val); |
| } |
| ia64_srlz_d(); |
| } |
| |
| /* |
| * propagate PMD from context to thread-state |
| */ |
| static inline void |
| pfm_copy_pmds(struct task_struct *task, pfm_context_t *ctx) |
| { |
| struct thread_struct *thread = &task->thread; |
| unsigned long ovfl_val = pmu_conf->ovfl_val; |
| unsigned long mask = ctx->ctx_all_pmds[0]; |
| unsigned long val; |
| int i; |
| |
| DPRINT(("mask=0x%lx\n", mask)); |
| |
| for (i=0; mask; i++, mask>>=1) { |
| |
| val = ctx->ctx_pmds[i].val; |
| |
| /* |
| * We break up the 64 bit value into 2 pieces |
| * the lower bits go to the machine state in the |
| * thread (will be reloaded on ctxsw in). |
| * The upper part stays in the soft-counter. |
| */ |
| if (PMD_IS_COUNTING(i)) { |
| ctx->ctx_pmds[i].val = val & ~ovfl_val; |
| val &= ovfl_val; |
| } |
| thread->pmds[i] = val; |
| |
| DPRINT(("pmd[%d]=0x%lx soft_val=0x%lx\n", |
| i, |
| thread->pmds[i], |
| ctx->ctx_pmds[i].val)); |
| } |
| } |
| |
| /* |
| * propagate PMC from context to thread-state |
| */ |
| static inline void |
| pfm_copy_pmcs(struct task_struct *task, pfm_context_t *ctx) |
| { |
| struct thread_struct *thread = &task->thread; |
| unsigned long mask = ctx->ctx_all_pmcs[0]; |
| int i; |
| |
| DPRINT(("mask=0x%lx\n", mask)); |
| |
| for (i=0; mask; i++, mask>>=1) { |
| /* masking 0 with ovfl_val yields 0 */ |
| thread->pmcs[i] = ctx->ctx_pmcs[i]; |
| DPRINT(("pmc[%d]=0x%lx\n", i, thread->pmcs[i])); |
| } |
| } |
| |
| |
| |
| static inline void |
| pfm_restore_pmcs(unsigned long *pmcs, unsigned long mask) |
| { |
| int i; |
| |
| for (i=0; mask; i++, mask>>=1) { |
| if ((mask & 0x1) == 0) continue; |
| ia64_set_pmc(i, pmcs[i]); |
| } |
| ia64_srlz_d(); |
| } |
| |
| static inline int |
| pfm_uuid_cmp(pfm_uuid_t a, pfm_uuid_t b) |
| { |
| return memcmp(a, b, sizeof(pfm_uuid_t)); |
| } |
| |
| static inline int |
| pfm_buf_fmt_exit(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, struct pt_regs *regs) |
| { |
| int ret = 0; |
| if (fmt->fmt_exit) ret = (*fmt->fmt_exit)(task, buf, regs); |
| return ret; |
| } |
| |
| static inline int |
| pfm_buf_fmt_getsize(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, int cpu, void *arg, unsigned long *size) |
| { |
| int ret = 0; |
| if (fmt->fmt_getsize) ret = (*fmt->fmt_getsize)(task, flags, cpu, arg, size); |
| return ret; |
| } |
| |
| |
| static inline int |
| pfm_buf_fmt_validate(pfm_buffer_fmt_t *fmt, struct task_struct *task, unsigned int flags, |
| int cpu, void *arg) |
| { |
| int ret = 0; |
| if (fmt->fmt_validate) ret = (*fmt->fmt_validate)(task, flags, cpu, arg); |
| return ret; |
| } |
| |
| static inline int |
| pfm_buf_fmt_init(pfm_buffer_fmt_t *fmt, struct task_struct *task, void *buf, unsigned int flags, |
| int cpu, void *arg) |
| { |
| int ret = 0; |
| if (fmt->fmt_init) ret = (*fmt->fmt_init)(task, buf, flags, cpu, arg); |
| return ret; |
| } |
| |
| static inline int |
| pfm_buf_fmt_restart(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs) |
| { |
| int ret = 0; |
| if (fmt->fmt_restart) ret = (*fmt->fmt_restart)(task, ctrl, buf, regs); |
| return ret; |
| } |
| |
| static inline int |
| pfm_buf_fmt_restart_active(pfm_buffer_fmt_t *fmt, struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs) |
| { |
| int ret = 0; |
| if (fmt->fmt_restart_active) ret = (*fmt->fmt_restart_active)(task, ctrl, buf, regs); |
| return ret; |
| } |
| |
| static pfm_buffer_fmt_t * |
| __pfm_find_buffer_fmt(pfm_uuid_t uuid) |
| { |
| struct list_head * pos; |
| pfm_buffer_fmt_t * entry; |
| |
| list_for_each(pos, &pfm_buffer_fmt_list) { |
| entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list); |
| if (pfm_uuid_cmp(uuid, entry->fmt_uuid) == 0) |
| return entry; |
| } |
| return NULL; |
| } |
| |
| /* |
| * find a buffer format based on its uuid |
| */ |
| static pfm_buffer_fmt_t * |
| pfm_find_buffer_fmt(pfm_uuid_t uuid) |
| { |
| pfm_buffer_fmt_t * fmt; |
| spin_lock(&pfm_buffer_fmt_lock); |
| fmt = __pfm_find_buffer_fmt(uuid); |
| spin_unlock(&pfm_buffer_fmt_lock); |
| return fmt; |
| } |
| |
| int |
| pfm_register_buffer_fmt(pfm_buffer_fmt_t *fmt) |
| { |
| int ret = 0; |
| |
| /* some sanity checks */ |
| if (fmt == NULL || fmt->fmt_name == NULL) return -EINVAL; |
| |
| /* we need at least a handler */ |
| if (fmt->fmt_handler == NULL) return -EINVAL; |
| |
| /* |
| * XXX: need check validity of fmt_arg_size |
| */ |
| |
| spin_lock(&pfm_buffer_fmt_lock); |
| |
| if (__pfm_find_buffer_fmt(fmt->fmt_uuid)) { |
| printk(KERN_ERR "perfmon: duplicate sampling format: %s\n", fmt->fmt_name); |
| ret = -EBUSY; |
| goto out; |
| } |
| list_add(&fmt->fmt_list, &pfm_buffer_fmt_list); |
| printk(KERN_INFO "perfmon: added sampling format %s\n", fmt->fmt_name); |
| |
| out: |
| spin_unlock(&pfm_buffer_fmt_lock); |
| return ret; |
| } |
| EXPORT_SYMBOL(pfm_register_buffer_fmt); |
| |
| int |
| pfm_unregister_buffer_fmt(pfm_uuid_t uuid) |
| { |
| pfm_buffer_fmt_t *fmt; |
| int ret = 0; |
| |
| spin_lock(&pfm_buffer_fmt_lock); |
| |
| fmt = __pfm_find_buffer_fmt(uuid); |
| if (!fmt) { |
| printk(KERN_ERR "perfmon: cannot unregister format, not found\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| list_del_init(&fmt->fmt_list); |
| printk(KERN_INFO "perfmon: removed sampling format: %s\n", fmt->fmt_name); |
| |
| out: |
| spin_unlock(&pfm_buffer_fmt_lock); |
| return ret; |
| |
| } |
| EXPORT_SYMBOL(pfm_unregister_buffer_fmt); |
| |
| extern void update_pal_halt_status(int); |
| |
| static int |
| pfm_reserve_session(struct task_struct *task, int is_syswide, unsigned int cpu) |
| { |
| unsigned long flags; |
| /* |
| * validy checks on cpu_mask have been done upstream |
| */ |
| LOCK_PFS(flags); |
| |
| DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", |
| pfm_sessions.pfs_sys_sessions, |
| pfm_sessions.pfs_task_sessions, |
| pfm_sessions.pfs_sys_use_dbregs, |
| is_syswide, |
| cpu)); |
| |
| if (is_syswide) { |
| /* |
| * cannot mix system wide and per-task sessions |
| */ |
| if (pfm_sessions.pfs_task_sessions > 0UL) { |
| DPRINT(("system wide not possible, %u conflicting task_sessions\n", |
| pfm_sessions.pfs_task_sessions)); |
| goto abort; |
| } |
| |
| if (pfm_sessions.pfs_sys_session[cpu]) goto error_conflict; |
| |
| DPRINT(("reserving system wide session on CPU%u currently on CPU%u\n", cpu, smp_processor_id())); |
| |
| pfm_sessions.pfs_sys_session[cpu] = task; |
| |
| pfm_sessions.pfs_sys_sessions++ ; |
| |
| } else { |
| if (pfm_sessions.pfs_sys_sessions) goto abort; |
| pfm_sessions.pfs_task_sessions++; |
| } |
| |
| DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", |
| pfm_sessions.pfs_sys_sessions, |
| pfm_sessions.pfs_task_sessions, |
| pfm_sessions.pfs_sys_use_dbregs, |
| is_syswide, |
| cpu)); |
| |
| /* |
| * disable default_idle() to go to PAL_HALT |
| */ |
| update_pal_halt_status(0); |
| |
| UNLOCK_PFS(flags); |
| |
| return 0; |
| |
| error_conflict: |
| DPRINT(("system wide not possible, conflicting session [%d] on CPU%d\n", |
| pfm_sessions.pfs_sys_session[cpu]->pid, |
| cpu)); |
| abort: |
| UNLOCK_PFS(flags); |
| |
| return -EBUSY; |
| |
| } |
| |
| static int |
| pfm_unreserve_session(pfm_context_t *ctx, int is_syswide, unsigned int cpu) |
| { |
| unsigned long flags; |
| /* |
| * validy checks on cpu_mask have been done upstream |
| */ |
| LOCK_PFS(flags); |
| |
| DPRINT(("in sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", |
| pfm_sessions.pfs_sys_sessions, |
| pfm_sessions.pfs_task_sessions, |
| pfm_sessions.pfs_sys_use_dbregs, |
| is_syswide, |
| cpu)); |
| |
| |
| if (is_syswide) { |
| pfm_sessions.pfs_sys_session[cpu] = NULL; |
| /* |
| * would not work with perfmon+more than one bit in cpu_mask |
| */ |
| if (ctx && ctx->ctx_fl_using_dbreg) { |
| if (pfm_sessions.pfs_sys_use_dbregs == 0) { |
| printk(KERN_ERR "perfmon: invalid release for ctx %p sys_use_dbregs=0\n", ctx); |
| } else { |
| pfm_sessions.pfs_sys_use_dbregs--; |
| } |
| } |
| pfm_sessions.pfs_sys_sessions--; |
| } else { |
| pfm_sessions.pfs_task_sessions--; |
| } |
| DPRINT(("out sys_sessions=%u task_sessions=%u dbregs=%u syswide=%d cpu=%u\n", |
| pfm_sessions.pfs_sys_sessions, |
| pfm_sessions.pfs_task_sessions, |
| pfm_sessions.pfs_sys_use_dbregs, |
| is_syswide, |
| cpu)); |
| |
| /* |
| * if possible, enable default_idle() to go into PAL_HALT |
| */ |
| if (pfm_sessions.pfs_task_sessions == 0 && pfm_sessions.pfs_sys_sessions == 0) |
| update_pal_halt_status(1); |
| |
| UNLOCK_PFS(flags); |
| |
| return 0; |
| } |
| |
| /* |
| * removes virtual mapping of the sampling buffer. |
| * IMPORTANT: cannot be called with interrupts disable, e.g. inside |
| * a PROTECT_CTX() section. |
| */ |
| static int |
| pfm_remove_smpl_mapping(struct task_struct *task, void *vaddr, unsigned long size) |
| { |
| int r; |
| |
| /* sanity checks */ |
| if (task->mm == NULL || size == 0UL || vaddr == NULL) { |
| printk(KERN_ERR "perfmon: pfm_remove_smpl_mapping [%d] invalid context mm=%p\n", task->pid, task->mm); |
| return -EINVAL; |
| } |
| |
| DPRINT(("smpl_vaddr=%p size=%lu\n", vaddr, size)); |
| |
| /* |
| * does the actual unmapping |
| */ |
| down_write(&task->mm->mmap_sem); |
| |
| DPRINT(("down_write done smpl_vaddr=%p size=%lu\n", vaddr, size)); |
| |
| r = pfm_do_munmap(task->mm, (unsigned long)vaddr, size, 0); |
| |
| up_write(&task->mm->mmap_sem); |
| if (r !=0) { |
| printk(KERN_ERR "perfmon: [%d] unable to unmap sampling buffer @%p size=%lu\n", task->pid, vaddr, size); |
| } |
| |
| DPRINT(("do_unmap(%p, %lu)=%d\n", vaddr, size, r)); |
| |
| return 0; |
| } |
| |
| /* |
| * free actual physical storage used by sampling buffer |
| */ |
| #if 0 |
| static int |
| pfm_free_smpl_buffer(pfm_context_t *ctx) |
| { |
| pfm_buffer_fmt_t *fmt; |
| |
| if (ctx->ctx_smpl_hdr == NULL) goto invalid_free; |
| |
| /* |
| * we won't use the buffer format anymore |
| */ |
| fmt = ctx->ctx_buf_fmt; |
| |
| DPRINT(("sampling buffer @%p size %lu vaddr=%p\n", |
| ctx->ctx_smpl_hdr, |
| ctx->ctx_smpl_size, |
| ctx->ctx_smpl_vaddr)); |
| |
| pfm_buf_fmt_exit(fmt, current, NULL, NULL); |
| |
| /* |
| * free the buffer |
| */ |
| pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size); |
| |
| ctx->ctx_smpl_hdr = NULL; |
| ctx->ctx_smpl_size = 0UL; |
| |
| return 0; |
| |
| invalid_free: |
| printk(KERN_ERR "perfmon: pfm_free_smpl_buffer [%d] no buffer\n", current->pid); |
| return -EINVAL; |
| } |
| #endif |
| |
| static inline void |
| pfm_exit_smpl_buffer(pfm_buffer_fmt_t *fmt) |
| { |
| if (fmt == NULL) return; |
| |
| pfm_buf_fmt_exit(fmt, current, NULL, NULL); |
| |
| } |
| |
| /* |
| * pfmfs should _never_ be mounted by userland - too much of security hassle, |
| * no real gain from having the whole whorehouse mounted. So we don't need |
| * any operations on the root directory. However, we need a non-trivial |
| * d_name - pfm: will go nicely and kill the special-casing in procfs. |
| */ |
| static struct vfsmount *pfmfs_mnt; |
| |
| static int __init |
| init_pfm_fs(void) |
| { |
| int err = register_filesystem(&pfm_fs_type); |
| if (!err) { |
| pfmfs_mnt = kern_mount(&pfm_fs_type); |
| err = PTR_ERR(pfmfs_mnt); |
| if (IS_ERR(pfmfs_mnt)) |
| unregister_filesystem(&pfm_fs_type); |
| else |
| err = 0; |
| } |
| return err; |
| } |
| |
| static void __exit |
| exit_pfm_fs(void) |
| { |
| unregister_filesystem(&pfm_fs_type); |
| mntput(pfmfs_mnt); |
| } |
| |
| static ssize_t |
| pfm_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos) |
| { |
| pfm_context_t *ctx; |
| pfm_msg_t *msg; |
| ssize_t ret; |
| unsigned long flags; |
| DECLARE_WAITQUEUE(wait, current); |
| if (PFM_IS_FILE(filp) == 0) { |
| printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid); |
| return -EINVAL; |
| } |
| |
| ctx = (pfm_context_t *)filp->private_data; |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: pfm_read: NULL ctx [%d]\n", current->pid); |
| return -EINVAL; |
| } |
| |
| /* |
| * check even when there is no message |
| */ |
| if (size < sizeof(pfm_msg_t)) { |
| DPRINT(("message is too small ctx=%p (>=%ld)\n", ctx, sizeof(pfm_msg_t))); |
| return -EINVAL; |
| } |
| |
| PROTECT_CTX(ctx, flags); |
| |
| /* |
| * put ourselves on the wait queue |
| */ |
| add_wait_queue(&ctx->ctx_msgq_wait, &wait); |
| |
| |
| for(;;) { |
| /* |
| * check wait queue |
| */ |
| |
| set_current_state(TASK_INTERRUPTIBLE); |
| |
| DPRINT(("head=%d tail=%d\n", ctx->ctx_msgq_head, ctx->ctx_msgq_tail)); |
| |
| ret = 0; |
| if(PFM_CTXQ_EMPTY(ctx) == 0) break; |
| |
| UNPROTECT_CTX(ctx, flags); |
| |
| /* |
| * check non-blocking read |
| */ |
| ret = -EAGAIN; |
| if(filp->f_flags & O_NONBLOCK) break; |
| |
| /* |
| * check pending signals |
| */ |
| if(signal_pending(current)) { |
| ret = -EINTR; |
| break; |
| } |
| /* |
| * no message, so wait |
| */ |
| schedule(); |
| |
| PROTECT_CTX(ctx, flags); |
| } |
| DPRINT(("[%d] back to running ret=%ld\n", current->pid, ret)); |
| set_current_state(TASK_RUNNING); |
| remove_wait_queue(&ctx->ctx_msgq_wait, &wait); |
| |
| if (ret < 0) goto abort; |
| |
| ret = -EINVAL; |
| msg = pfm_get_next_msg(ctx); |
| if (msg == NULL) { |
| printk(KERN_ERR "perfmon: pfm_read no msg for ctx=%p [%d]\n", ctx, current->pid); |
| goto abort_locked; |
| } |
| |
| DPRINT(("fd=%d type=%d\n", msg->pfm_gen_msg.msg_ctx_fd, msg->pfm_gen_msg.msg_type)); |
| |
| ret = -EFAULT; |
| if(copy_to_user(buf, msg, sizeof(pfm_msg_t)) == 0) ret = sizeof(pfm_msg_t); |
| |
| abort_locked: |
| UNPROTECT_CTX(ctx, flags); |
| abort: |
| return ret; |
| } |
| |
| static ssize_t |
| pfm_write(struct file *file, const char __user *ubuf, |
| size_t size, loff_t *ppos) |
| { |
| DPRINT(("pfm_write called\n")); |
| return -EINVAL; |
| } |
| |
| static unsigned int |
| pfm_poll(struct file *filp, poll_table * wait) |
| { |
| pfm_context_t *ctx; |
| unsigned long flags; |
| unsigned int mask = 0; |
| |
| if (PFM_IS_FILE(filp) == 0) { |
| printk(KERN_ERR "perfmon: pfm_poll: bad magic [%d]\n", current->pid); |
| return 0; |
| } |
| |
| ctx = (pfm_context_t *)filp->private_data; |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: pfm_poll: NULL ctx [%d]\n", current->pid); |
| return 0; |
| } |
| |
| |
| DPRINT(("pfm_poll ctx_fd=%d before poll_wait\n", ctx->ctx_fd)); |
| |
| poll_wait(filp, &ctx->ctx_msgq_wait, wait); |
| |
| PROTECT_CTX(ctx, flags); |
| |
| if (PFM_CTXQ_EMPTY(ctx) == 0) |
| mask = POLLIN | POLLRDNORM; |
| |
| UNPROTECT_CTX(ctx, flags); |
| |
| DPRINT(("pfm_poll ctx_fd=%d mask=0x%x\n", ctx->ctx_fd, mask)); |
| |
| return mask; |
| } |
| |
| static int |
| pfm_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) |
| { |
| DPRINT(("pfm_ioctl called\n")); |
| return -EINVAL; |
| } |
| |
| /* |
| * interrupt cannot be masked when coming here |
| */ |
| static inline int |
| pfm_do_fasync(int fd, struct file *filp, pfm_context_t *ctx, int on) |
| { |
| int ret; |
| |
| ret = fasync_helper (fd, filp, on, &ctx->ctx_async_queue); |
| |
| DPRINT(("pfm_fasync called by [%d] on ctx_fd=%d on=%d async_queue=%p ret=%d\n", |
| current->pid, |
| fd, |
| on, |
| ctx->ctx_async_queue, ret)); |
| |
| return ret; |
| } |
| |
| static int |
| pfm_fasync(int fd, struct file *filp, int on) |
| { |
| pfm_context_t *ctx; |
| int ret; |
| |
| if (PFM_IS_FILE(filp) == 0) { |
| printk(KERN_ERR "perfmon: pfm_fasync bad magic [%d]\n", current->pid); |
| return -EBADF; |
| } |
| |
| ctx = (pfm_context_t *)filp->private_data; |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: pfm_fasync NULL ctx [%d]\n", current->pid); |
| return -EBADF; |
| } |
| /* |
| * we cannot mask interrupts during this call because this may |
| * may go to sleep if memory is not readily avalaible. |
| * |
| * We are protected from the conetxt disappearing by the get_fd()/put_fd() |
| * done in caller. Serialization of this function is ensured by caller. |
| */ |
| ret = pfm_do_fasync(fd, filp, ctx, on); |
| |
| |
| DPRINT(("pfm_fasync called on ctx_fd=%d on=%d async_queue=%p ret=%d\n", |
| fd, |
| on, |
| ctx->ctx_async_queue, ret)); |
| |
| return ret; |
| } |
| |
| #ifdef CONFIG_SMP |
| /* |
| * this function is exclusively called from pfm_close(). |
| * The context is not protected at that time, nor are interrupts |
| * on the remote CPU. That's necessary to avoid deadlocks. |
| */ |
| static void |
| pfm_syswide_force_stop(void *info) |
| { |
| pfm_context_t *ctx = (pfm_context_t *)info; |
| struct pt_regs *regs = ia64_task_regs(current); |
| struct task_struct *owner; |
| unsigned long flags; |
| int ret; |
| |
| if (ctx->ctx_cpu != smp_processor_id()) { |
| printk(KERN_ERR "perfmon: pfm_syswide_force_stop for CPU%d but on CPU%d\n", |
| ctx->ctx_cpu, |
| smp_processor_id()); |
| return; |
| } |
| owner = GET_PMU_OWNER(); |
| if (owner != ctx->ctx_task) { |
| printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected owner [%d] instead of [%d]\n", |
| smp_processor_id(), |
| owner->pid, ctx->ctx_task->pid); |
| return; |
| } |
| if (GET_PMU_CTX() != ctx) { |
| printk(KERN_ERR "perfmon: pfm_syswide_force_stop CPU%d unexpected ctx %p instead of %p\n", |
| smp_processor_id(), |
| GET_PMU_CTX(), ctx); |
| return; |
| } |
| |
| DPRINT(("on CPU%d forcing system wide stop for [%d]\n", smp_processor_id(), ctx->ctx_task->pid)); |
| /* |
| * the context is already protected in pfm_close(), we simply |
| * need to mask interrupts to avoid a PMU interrupt race on |
| * this CPU |
| */ |
| local_irq_save(flags); |
| |
| ret = pfm_context_unload(ctx, NULL, 0, regs); |
| if (ret) { |
| DPRINT(("context_unload returned %d\n", ret)); |
| } |
| |
| /* |
| * unmask interrupts, PMU interrupts are now spurious here |
| */ |
| local_irq_restore(flags); |
| } |
| |
| static void |
| pfm_syswide_cleanup_other_cpu(pfm_context_t *ctx) |
| { |
| int ret; |
| |
| DPRINT(("calling CPU%d for cleanup\n", ctx->ctx_cpu)); |
| ret = smp_call_function_single(ctx->ctx_cpu, pfm_syswide_force_stop, ctx, 0, 1); |
| DPRINT(("called CPU%d for cleanup ret=%d\n", ctx->ctx_cpu, ret)); |
| } |
| #endif /* CONFIG_SMP */ |
| |
| /* |
| * called for each close(). Partially free resources. |
| * When caller is self-monitoring, the context is unloaded. |
| */ |
| static int |
| pfm_flush(struct file *filp) |
| { |
| pfm_context_t *ctx; |
| struct task_struct *task; |
| struct pt_regs *regs; |
| unsigned long flags; |
| unsigned long smpl_buf_size = 0UL; |
| void *smpl_buf_vaddr = NULL; |
| int state, is_system; |
| |
| if (PFM_IS_FILE(filp) == 0) { |
| DPRINT(("bad magic for\n")); |
| return -EBADF; |
| } |
| |
| ctx = (pfm_context_t *)filp->private_data; |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: pfm_flush: NULL ctx [%d]\n", current->pid); |
| return -EBADF; |
| } |
| |
| /* |
| * remove our file from the async queue, if we use this mode. |
| * This can be done without the context being protected. We come |
| * here when the context has become unreacheable by other tasks. |
| * |
| * We may still have active monitoring at this point and we may |
| * end up in pfm_overflow_handler(). However, fasync_helper() |
| * operates with interrupts disabled and it cleans up the |
| * queue. If the PMU handler is called prior to entering |
| * fasync_helper() then it will send a signal. If it is |
| * invoked after, it will find an empty queue and no |
| * signal will be sent. In both case, we are safe |
| */ |
| if (filp->f_flags & FASYNC) { |
| DPRINT(("cleaning up async_queue=%p\n", ctx->ctx_async_queue)); |
| pfm_do_fasync (-1, filp, ctx, 0); |
| } |
| |
| PROTECT_CTX(ctx, flags); |
| |
| state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| |
| task = PFM_CTX_TASK(ctx); |
| regs = ia64_task_regs(task); |
| |
| DPRINT(("ctx_state=%d is_current=%d\n", |
| state, |
| task == current ? 1 : 0)); |
| |
| /* |
| * if state == UNLOADED, then task is NULL |
| */ |
| |
| /* |
| * we must stop and unload because we are losing access to the context. |
| */ |
| if (task == current) { |
| #ifdef CONFIG_SMP |
| /* |
| * the task IS the owner but it migrated to another CPU: that's bad |
| * but we must handle this cleanly. Unfortunately, the kernel does |
| * not provide a mechanism to block migration (while the context is loaded). |
| * |
| * We need to release the resource on the ORIGINAL cpu. |
| */ |
| if (is_system && ctx->ctx_cpu != smp_processor_id()) { |
| |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| /* |
| * keep context protected but unmask interrupt for IPI |
| */ |
| local_irq_restore(flags); |
| |
| pfm_syswide_cleanup_other_cpu(ctx); |
| |
| /* |
| * restore interrupt masking |
| */ |
| local_irq_save(flags); |
| |
| /* |
| * context is unloaded at this point |
| */ |
| } else |
| #endif /* CONFIG_SMP */ |
| { |
| |
| DPRINT(("forcing unload\n")); |
| /* |
| * stop and unload, returning with state UNLOADED |
| * and session unreserved. |
| */ |
| pfm_context_unload(ctx, NULL, 0, regs); |
| |
| DPRINT(("ctx_state=%d\n", ctx->ctx_state)); |
| } |
| } |
| |
| /* |
| * remove virtual mapping, if any, for the calling task. |
| * cannot reset ctx field until last user is calling close(). |
| * |
| * ctx_smpl_vaddr must never be cleared because it is needed |
| * by every task with access to the context |
| * |
| * When called from do_exit(), the mm context is gone already, therefore |
| * mm is NULL, i.e., the VMA is already gone and we do not have to |
| * do anything here |
| */ |
| if (ctx->ctx_smpl_vaddr && current->mm) { |
| smpl_buf_vaddr = ctx->ctx_smpl_vaddr; |
| smpl_buf_size = ctx->ctx_smpl_size; |
| } |
| |
| UNPROTECT_CTX(ctx, flags); |
| |
| /* |
| * if there was a mapping, then we systematically remove it |
| * at this point. Cannot be done inside critical section |
| * because some VM function reenables interrupts. |
| * |
| */ |
| if (smpl_buf_vaddr) pfm_remove_smpl_mapping(current, smpl_buf_vaddr, smpl_buf_size); |
| |
| return 0; |
| } |
| /* |
| * called either on explicit close() or from exit_files(). |
| * Only the LAST user of the file gets to this point, i.e., it is |
| * called only ONCE. |
| * |
| * IMPORTANT: we get called ONLY when the refcnt on the file gets to zero |
| * (fput()),i.e, last task to access the file. Nobody else can access the |
| * file at this point. |
| * |
| * When called from exit_files(), the VMA has been freed because exit_mm() |
| * is executed before exit_files(). |
| * |
| * When called from exit_files(), the current task is not yet ZOMBIE but we |
| * flush the PMU state to the context. |
| */ |
| static int |
| pfm_close(struct inode *inode, struct file *filp) |
| { |
| pfm_context_t *ctx; |
| struct task_struct *task; |
| struct pt_regs *regs; |
| DECLARE_WAITQUEUE(wait, current); |
| unsigned long flags; |
| unsigned long smpl_buf_size = 0UL; |
| void *smpl_buf_addr = NULL; |
| int free_possible = 1; |
| int state, is_system; |
| |
| DPRINT(("pfm_close called private=%p\n", filp->private_data)); |
| |
| if (PFM_IS_FILE(filp) == 0) { |
| DPRINT(("bad magic\n")); |
| return -EBADF; |
| } |
| |
| ctx = (pfm_context_t *)filp->private_data; |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: pfm_close: NULL ctx [%d]\n", current->pid); |
| return -EBADF; |
| } |
| |
| PROTECT_CTX(ctx, flags); |
| |
| state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| |
| task = PFM_CTX_TASK(ctx); |
| regs = ia64_task_regs(task); |
| |
| DPRINT(("ctx_state=%d is_current=%d\n", |
| state, |
| task == current ? 1 : 0)); |
| |
| /* |
| * if task == current, then pfm_flush() unloaded the context |
| */ |
| if (state == PFM_CTX_UNLOADED) goto doit; |
| |
| /* |
| * context is loaded/masked and task != current, we need to |
| * either force an unload or go zombie |
| */ |
| |
| /* |
| * The task is currently blocked or will block after an overflow. |
| * we must force it to wakeup to get out of the |
| * MASKED state and transition to the unloaded state by itself. |
| * |
| * This situation is only possible for per-task mode |
| */ |
| if (state == PFM_CTX_MASKED && CTX_OVFL_NOBLOCK(ctx) == 0) { |
| |
| /* |
| * set a "partial" zombie state to be checked |
| * upon return from down() in pfm_handle_work(). |
| * |
| * We cannot use the ZOMBIE state, because it is checked |
| * by pfm_load_regs() which is called upon wakeup from down(). |
| * In such case, it would free the context and then we would |
| * return to pfm_handle_work() which would access the |
| * stale context. Instead, we set a flag invisible to pfm_load_regs() |
| * but visible to pfm_handle_work(). |
| * |
| * For some window of time, we have a zombie context with |
| * ctx_state = MASKED and not ZOMBIE |
| */ |
| ctx->ctx_fl_going_zombie = 1; |
| |
| /* |
| * force task to wake up from MASKED state |
| */ |
| up(&ctx->ctx_restart_sem); |
| |
| DPRINT(("waking up ctx_state=%d\n", state)); |
| |
| /* |
| * put ourself to sleep waiting for the other |
| * task to report completion |
| * |
| * the context is protected by mutex, therefore there |
| * is no risk of being notified of completion before |
| * begin actually on the waitq. |
| */ |
| set_current_state(TASK_INTERRUPTIBLE); |
| add_wait_queue(&ctx->ctx_zombieq, &wait); |
| |
| UNPROTECT_CTX(ctx, flags); |
| |
| /* |
| * XXX: check for signals : |
| * - ok for explicit close |
| * - not ok when coming from exit_files() |
| */ |
| schedule(); |
| |
| |
| PROTECT_CTX(ctx, flags); |
| |
| |
| remove_wait_queue(&ctx->ctx_zombieq, &wait); |
| set_current_state(TASK_RUNNING); |
| |
| /* |
| * context is unloaded at this point |
| */ |
| DPRINT(("after zombie wakeup ctx_state=%d for\n", state)); |
| } |
| else if (task != current) { |
| #ifdef CONFIG_SMP |
| /* |
| * switch context to zombie state |
| */ |
| ctx->ctx_state = PFM_CTX_ZOMBIE; |
| |
| DPRINT(("zombie ctx for [%d]\n", task->pid)); |
| /* |
| * cannot free the context on the spot. deferred until |
| * the task notices the ZOMBIE state |
| */ |
| free_possible = 0; |
| #else |
| pfm_context_unload(ctx, NULL, 0, regs); |
| #endif |
| } |
| |
| doit: |
| /* reload state, may have changed during opening of critical section */ |
| state = ctx->ctx_state; |
| |
| /* |
| * the context is still attached to a task (possibly current) |
| * we cannot destroy it right now |
| */ |
| |
| /* |
| * we must free the sampling buffer right here because |
| * we cannot rely on it being cleaned up later by the |
| * monitored task. It is not possible to free vmalloc'ed |
| * memory in pfm_load_regs(). Instead, we remove the buffer |
| * now. should there be subsequent PMU overflow originally |
| * meant for sampling, the will be converted to spurious |
| * and that's fine because the monitoring tools is gone anyway. |
| */ |
| if (ctx->ctx_smpl_hdr) { |
| smpl_buf_addr = ctx->ctx_smpl_hdr; |
| smpl_buf_size = ctx->ctx_smpl_size; |
| /* no more sampling */ |
| ctx->ctx_smpl_hdr = NULL; |
| ctx->ctx_fl_is_sampling = 0; |
| } |
| |
| DPRINT(("ctx_state=%d free_possible=%d addr=%p size=%lu\n", |
| state, |
| free_possible, |
| smpl_buf_addr, |
| smpl_buf_size)); |
| |
| if (smpl_buf_addr) pfm_exit_smpl_buffer(ctx->ctx_buf_fmt); |
| |
| /* |
| * UNLOADED that the session has already been unreserved. |
| */ |
| if (state == PFM_CTX_ZOMBIE) { |
| pfm_unreserve_session(ctx, ctx->ctx_fl_system , ctx->ctx_cpu); |
| } |
| |
| /* |
| * disconnect file descriptor from context must be done |
| * before we unlock. |
| */ |
| filp->private_data = NULL; |
| |
| /* |
| * if we free on the spot, the context is now completely unreacheable |
| * from the callers side. The monitored task side is also cut, so we |
| * can freely cut. |
| * |
| * If we have a deferred free, only the caller side is disconnected. |
| */ |
| UNPROTECT_CTX(ctx, flags); |
| |
| /* |
| * All memory free operations (especially for vmalloc'ed memory) |
| * MUST be done with interrupts ENABLED. |
| */ |
| if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size); |
| |
| /* |
| * return the memory used by the context |
| */ |
| if (free_possible) pfm_context_free(ctx); |
| |
| return 0; |
| } |
| |
| static int |
| pfm_no_open(struct inode *irrelevant, struct file *dontcare) |
| { |
| DPRINT(("pfm_no_open called\n")); |
| return -ENXIO; |
| } |
| |
| |
| |
| static struct file_operations pfm_file_ops = { |
| .llseek = no_llseek, |
| .read = pfm_read, |
| .write = pfm_write, |
| .poll = pfm_poll, |
| .ioctl = pfm_ioctl, |
| .open = pfm_no_open, /* special open code to disallow open via /proc */ |
| .fasync = pfm_fasync, |
| .release = pfm_close, |
| .flush = pfm_flush |
| }; |
| |
| static int |
| pfmfs_delete_dentry(struct dentry *dentry) |
| { |
| return 1; |
| } |
| |
| static struct dentry_operations pfmfs_dentry_operations = { |
| .d_delete = pfmfs_delete_dentry, |
| }; |
| |
| |
| static int |
| pfm_alloc_fd(struct file **cfile) |
| { |
| int fd, ret = 0; |
| struct file *file = NULL; |
| struct inode * inode; |
| char name[32]; |
| struct qstr this; |
| |
| fd = get_unused_fd(); |
| if (fd < 0) return -ENFILE; |
| |
| ret = -ENFILE; |
| |
| file = get_empty_filp(); |
| if (!file) goto out; |
| |
| /* |
| * allocate a new inode |
| */ |
| inode = new_inode(pfmfs_mnt->mnt_sb); |
| if (!inode) goto out; |
| |
| DPRINT(("new inode ino=%ld @%p\n", inode->i_ino, inode)); |
| |
| inode->i_mode = S_IFCHR|S_IRUGO; |
| inode->i_uid = current->fsuid; |
| inode->i_gid = current->fsgid; |
| |
| sprintf(name, "[%lu]", inode->i_ino); |
| this.name = name; |
| this.len = strlen(name); |
| this.hash = inode->i_ino; |
| |
| ret = -ENOMEM; |
| |
| /* |
| * allocate a new dcache entry |
| */ |
| file->f_dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this); |
| if (!file->f_dentry) goto out; |
| |
| file->f_dentry->d_op = &pfmfs_dentry_operations; |
| |
| d_add(file->f_dentry, inode); |
| file->f_vfsmnt = mntget(pfmfs_mnt); |
| file->f_mapping = inode->i_mapping; |
| |
| file->f_op = &pfm_file_ops; |
| file->f_mode = FMODE_READ; |
| file->f_flags = O_RDONLY; |
| file->f_pos = 0; |
| |
| /* |
| * may have to delay until context is attached? |
| */ |
| fd_install(fd, file); |
| |
| /* |
| * the file structure we will use |
| */ |
| *cfile = file; |
| |
| return fd; |
| out: |
| if (file) put_filp(file); |
| put_unused_fd(fd); |
| return ret; |
| } |
| |
| static void |
| pfm_free_fd(int fd, struct file *file) |
| { |
| struct files_struct *files = current->files; |
| struct fdtable *fdt = files_fdtable(files); |
| |
| /* |
| * there ie no fd_uninstall(), so we do it here |
| */ |
| spin_lock(&files->file_lock); |
| rcu_assign_pointer(fdt->fd[fd], NULL); |
| spin_unlock(&files->file_lock); |
| |
| if (file) |
| put_filp(file); |
| put_unused_fd(fd); |
| } |
| |
| static int |
| pfm_remap_buffer(struct vm_area_struct *vma, unsigned long buf, unsigned long addr, unsigned long size) |
| { |
| DPRINT(("CPU%d buf=0x%lx addr=0x%lx size=%ld\n", smp_processor_id(), buf, addr, size)); |
| |
| while (size > 0) { |
| unsigned long pfn = ia64_tpa(buf) >> PAGE_SHIFT; |
| |
| |
| if (remap_pfn_range(vma, addr, pfn, PAGE_SIZE, PAGE_READONLY)) |
| return -ENOMEM; |
| |
| addr += PAGE_SIZE; |
| buf += PAGE_SIZE; |
| size -= PAGE_SIZE; |
| } |
| return 0; |
| } |
| |
| /* |
| * allocate a sampling buffer and remaps it into the user address space of the task |
| */ |
| static int |
| pfm_smpl_buffer_alloc(struct task_struct *task, pfm_context_t *ctx, unsigned long rsize, void **user_vaddr) |
| { |
| struct mm_struct *mm = task->mm; |
| struct vm_area_struct *vma = NULL; |
| unsigned long size; |
| void *smpl_buf; |
| |
| |
| /* |
| * the fixed header + requested size and align to page boundary |
| */ |
| size = PAGE_ALIGN(rsize); |
| |
| DPRINT(("sampling buffer rsize=%lu size=%lu bytes\n", rsize, size)); |
| |
| /* |
| * check requested size to avoid Denial-of-service attacks |
| * XXX: may have to refine this test |
| * Check against address space limit. |
| * |
| * if ((mm->total_vm << PAGE_SHIFT) + len> task->rlim[RLIMIT_AS].rlim_cur) |
| * return -ENOMEM; |
| */ |
| if (size > task->signal->rlim[RLIMIT_MEMLOCK].rlim_cur) |
| return -ENOMEM; |
| |
| /* |
| * We do the easy to undo allocations first. |
| * |
| * pfm_rvmalloc(), clears the buffer, so there is no leak |
| */ |
| smpl_buf = pfm_rvmalloc(size); |
| if (smpl_buf == NULL) { |
| DPRINT(("Can't allocate sampling buffer\n")); |
| return -ENOMEM; |
| } |
| |
| DPRINT(("smpl_buf @%p\n", smpl_buf)); |
| |
| /* allocate vma */ |
| vma = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL); |
| if (!vma) { |
| DPRINT(("Cannot allocate vma\n")); |
| goto error_kmem; |
| } |
| memset(vma, 0, sizeof(*vma)); |
| |
| /* |
| * partially initialize the vma for the sampling buffer |
| */ |
| vma->vm_mm = mm; |
| vma->vm_flags = VM_READ| VM_MAYREAD |VM_RESERVED; |
| vma->vm_page_prot = PAGE_READONLY; /* XXX may need to change */ |
| |
| /* |
| * Now we have everything we need and we can initialize |
| * and connect all the data structures |
| */ |
| |
| ctx->ctx_smpl_hdr = smpl_buf; |
| ctx->ctx_smpl_size = size; /* aligned size */ |
| |
| /* |
| * Let's do the difficult operations next. |
| * |
| * now we atomically find some area in the address space and |
| * remap the buffer in it. |
| */ |
| down_write(&task->mm->mmap_sem); |
| |
| /* find some free area in address space, must have mmap sem held */ |
| vma->vm_start = pfm_get_unmapped_area(NULL, 0, size, 0, MAP_PRIVATE|MAP_ANONYMOUS, 0); |
| if (vma->vm_start == 0UL) { |
| DPRINT(("Cannot find unmapped area for size %ld\n", size)); |
| up_write(&task->mm->mmap_sem); |
| goto error; |
| } |
| vma->vm_end = vma->vm_start + size; |
| vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT; |
| |
| DPRINT(("aligned size=%ld, hdr=%p mapped @0x%lx\n", size, ctx->ctx_smpl_hdr, vma->vm_start)); |
| |
| /* can only be applied to current task, need to have the mm semaphore held when called */ |
| if (pfm_remap_buffer(vma, (unsigned long)smpl_buf, vma->vm_start, size)) { |
| DPRINT(("Can't remap buffer\n")); |
| up_write(&task->mm->mmap_sem); |
| goto error; |
| } |
| |
| /* |
| * now insert the vma in the vm list for the process, must be |
| * done with mmap lock held |
| */ |
| insert_vm_struct(mm, vma); |
| |
| mm->total_vm += size >> PAGE_SHIFT; |
| vm_stat_account(vma); |
| up_write(&task->mm->mmap_sem); |
| |
| /* |
| * keep track of user level virtual address |
| */ |
| ctx->ctx_smpl_vaddr = (void *)vma->vm_start; |
| *(unsigned long *)user_vaddr = vma->vm_start; |
| |
| return 0; |
| |
| error: |
| kmem_cache_free(vm_area_cachep, vma); |
| error_kmem: |
| pfm_rvfree(smpl_buf, size); |
| |
| return -ENOMEM; |
| } |
| |
| /* |
| * XXX: do something better here |
| */ |
| static int |
| pfm_bad_permissions(struct task_struct *task) |
| { |
| /* inspired by ptrace_attach() */ |
| DPRINT(("cur: uid=%d gid=%d task: euid=%d suid=%d uid=%d egid=%d sgid=%d\n", |
| current->uid, |
| current->gid, |
| task->euid, |
| task->suid, |
| task->uid, |
| task->egid, |
| task->sgid)); |
| |
| return ((current->uid != task->euid) |
| || (current->uid != task->suid) |
| || (current->uid != task->uid) |
| || (current->gid != task->egid) |
| || (current->gid != task->sgid) |
| || (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE); |
| } |
| |
| static int |
| pfarg_is_sane(struct task_struct *task, pfarg_context_t *pfx) |
| { |
| int ctx_flags; |
| |
| /* valid signal */ |
| |
| ctx_flags = pfx->ctx_flags; |
| |
| if (ctx_flags & PFM_FL_SYSTEM_WIDE) { |
| |
| /* |
| * cannot block in this mode |
| */ |
| if (ctx_flags & PFM_FL_NOTIFY_BLOCK) { |
| DPRINT(("cannot use blocking mode when in system wide monitoring\n")); |
| return -EINVAL; |
| } |
| } else { |
| } |
| /* probably more to add here */ |
| |
| return 0; |
| } |
| |
| static int |
| pfm_setup_buffer_fmt(struct task_struct *task, pfm_context_t *ctx, unsigned int ctx_flags, |
| unsigned int cpu, pfarg_context_t *arg) |
| { |
| pfm_buffer_fmt_t *fmt = NULL; |
| unsigned long size = 0UL; |
| void *uaddr = NULL; |
| void *fmt_arg = NULL; |
| int ret = 0; |
| #define PFM_CTXARG_BUF_ARG(a) (pfm_buffer_fmt_t *)(a+1) |
| |
| /* invoke and lock buffer format, if found */ |
| fmt = pfm_find_buffer_fmt(arg->ctx_smpl_buf_id); |
| if (fmt == NULL) { |
| DPRINT(("[%d] cannot find buffer format\n", task->pid)); |
| return -EINVAL; |
| } |
| |
| /* |
| * buffer argument MUST be contiguous to pfarg_context_t |
| */ |
| if (fmt->fmt_arg_size) fmt_arg = PFM_CTXARG_BUF_ARG(arg); |
| |
| ret = pfm_buf_fmt_validate(fmt, task, ctx_flags, cpu, fmt_arg); |
| |
| DPRINT(("[%d] after validate(0x%x,%d,%p)=%d\n", task->pid, ctx_flags, cpu, fmt_arg, ret)); |
| |
| if (ret) goto error; |
| |
| /* link buffer format and context */ |
| ctx->ctx_buf_fmt = fmt; |
| |
| /* |
| * check if buffer format wants to use perfmon buffer allocation/mapping service |
| */ |
| ret = pfm_buf_fmt_getsize(fmt, task, ctx_flags, cpu, fmt_arg, &size); |
| if (ret) goto error; |
| |
| if (size) { |
| /* |
| * buffer is always remapped into the caller's address space |
| */ |
| ret = pfm_smpl_buffer_alloc(current, ctx, size, &uaddr); |
| if (ret) goto error; |
| |
| /* keep track of user address of buffer */ |
| arg->ctx_smpl_vaddr = uaddr; |
| } |
| ret = pfm_buf_fmt_init(fmt, task, ctx->ctx_smpl_hdr, ctx_flags, cpu, fmt_arg); |
| |
| error: |
| return ret; |
| } |
| |
| static void |
| pfm_reset_pmu_state(pfm_context_t *ctx) |
| { |
| int i; |
| |
| /* |
| * install reset values for PMC. |
| */ |
| for (i=1; PMC_IS_LAST(i) == 0; i++) { |
| if (PMC_IS_IMPL(i) == 0) continue; |
| ctx->ctx_pmcs[i] = PMC_DFL_VAL(i); |
| DPRINT(("pmc[%d]=0x%lx\n", i, ctx->ctx_pmcs[i])); |
| } |
| /* |
| * PMD registers are set to 0UL when the context in memset() |
| */ |
| |
| /* |
| * On context switched restore, we must restore ALL pmc and ALL pmd even |
| * when they are not actively used by the task. In UP, the incoming process |
| * may otherwise pick up left over PMC, PMD state from the previous process. |
| * As opposed to PMD, stale PMC can cause harm to the incoming |
| * process because they may change what is being measured. |
| * Therefore, we must systematically reinstall the entire |
| * PMC state. In SMP, the same thing is possible on the |
| * same CPU but also on between 2 CPUs. |
| * |
| * The problem with PMD is information leaking especially |
| * to user level when psr.sp=0 |
| * |
| * There is unfortunately no easy way to avoid this problem |
| * on either UP or SMP. This definitively slows down the |
| * pfm_load_regs() function. |
| */ |
| |
| /* |
| * bitmask of all PMCs accessible to this context |
| * |
| * PMC0 is treated differently. |
| */ |
| ctx->ctx_all_pmcs[0] = pmu_conf->impl_pmcs[0] & ~0x1; |
| |
| /* |
| * bitmask of all PMDs that are accesible to this context |
| */ |
| ctx->ctx_all_pmds[0] = pmu_conf->impl_pmds[0]; |
| |
| DPRINT(("<%d> all_pmcs=0x%lx all_pmds=0x%lx\n", ctx->ctx_fd, ctx->ctx_all_pmcs[0],ctx->ctx_all_pmds[0])); |
| |
| /* |
| * useful in case of re-enable after disable |
| */ |
| ctx->ctx_used_ibrs[0] = 0UL; |
| ctx->ctx_used_dbrs[0] = 0UL; |
| } |
| |
| static int |
| pfm_ctx_getsize(void *arg, size_t *sz) |
| { |
| pfarg_context_t *req = (pfarg_context_t *)arg; |
| pfm_buffer_fmt_t *fmt; |
| |
| *sz = 0; |
| |
| if (!pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) return 0; |
| |
| fmt = pfm_find_buffer_fmt(req->ctx_smpl_buf_id); |
| if (fmt == NULL) { |
| DPRINT(("cannot find buffer format\n")); |
| return -EINVAL; |
| } |
| /* get just enough to copy in user parameters */ |
| *sz = fmt->fmt_arg_size; |
| DPRINT(("arg_size=%lu\n", *sz)); |
| |
| return 0; |
| } |
| |
| |
| |
| /* |
| * cannot attach if : |
| * - kernel task |
| * - task not owned by caller |
| * - task incompatible with context mode |
| */ |
| static int |
| pfm_task_incompatible(pfm_context_t *ctx, struct task_struct *task) |
| { |
| /* |
| * no kernel task or task not owner by caller |
| */ |
| if (task->mm == NULL) { |
| DPRINT(("task [%d] has not memory context (kernel thread)\n", task->pid)); |
| return -EPERM; |
| } |
| if (pfm_bad_permissions(task)) { |
| DPRINT(("no permission to attach to [%d]\n", task->pid)); |
| return -EPERM; |
| } |
| /* |
| * cannot block in self-monitoring mode |
| */ |
| if (CTX_OVFL_NOBLOCK(ctx) == 0 && task == current) { |
| DPRINT(("cannot load a blocking context on self for [%d]\n", task->pid)); |
| return -EINVAL; |
| } |
| |
| if (task->exit_state == EXIT_ZOMBIE) { |
| DPRINT(("cannot attach to zombie task [%d]\n", task->pid)); |
| return -EBUSY; |
| } |
| |
| /* |
| * always ok for self |
| */ |
| if (task == current) return 0; |
| |
| if ((task->state != TASK_STOPPED) && (task->state != TASK_TRACED)) { |
| DPRINT(("cannot attach to non-stopped task [%d] state=%ld\n", task->pid, task->state)); |
| return -EBUSY; |
| } |
| /* |
| * make sure the task is off any CPU |
| */ |
| wait_task_inactive(task); |
| |
| /* more to come... */ |
| |
| return 0; |
| } |
| |
| static int |
| pfm_get_task(pfm_context_t *ctx, pid_t pid, struct task_struct **task) |
| { |
| struct task_struct *p = current; |
| int ret; |
| |
| /* XXX: need to add more checks here */ |
| if (pid < 2) return -EPERM; |
| |
| if (pid != current->pid) { |
| |
| read_lock(&tasklist_lock); |
| |
| p = find_task_by_pid(pid); |
| |
| /* make sure task cannot go away while we operate on it */ |
| if (p) get_task_struct(p); |
| |
| read_unlock(&tasklist_lock); |
| |
| if (p == NULL) return -ESRCH; |
| } |
| |
| ret = pfm_task_incompatible(ctx, p); |
| if (ret == 0) { |
| *task = p; |
| } else if (p != current) { |
| pfm_put_task(p); |
| } |
| return ret; |
| } |
| |
| |
| |
| static int |
| pfm_context_create(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| pfarg_context_t *req = (pfarg_context_t *)arg; |
| struct file *filp; |
| int ctx_flags; |
| int ret; |
| |
| /* let's check the arguments first */ |
| ret = pfarg_is_sane(current, req); |
| if (ret < 0) return ret; |
| |
| ctx_flags = req->ctx_flags; |
| |
| ret = -ENOMEM; |
| |
| ctx = pfm_context_alloc(); |
| if (!ctx) goto error; |
| |
| ret = pfm_alloc_fd(&filp); |
| if (ret < 0) goto error_file; |
| |
| req->ctx_fd = ctx->ctx_fd = ret; |
| |
| /* |
| * attach context to file |
| */ |
| filp->private_data = ctx; |
| |
| /* |
| * does the user want to sample? |
| */ |
| if (pfm_uuid_cmp(req->ctx_smpl_buf_id, pfm_null_uuid)) { |
| ret = pfm_setup_buffer_fmt(current, ctx, ctx_flags, 0, req); |
| if (ret) goto buffer_error; |
| } |
| |
| /* |
| * init context protection lock |
| */ |
| spin_lock_init(&ctx->ctx_lock); |
| |
| /* |
| * context is unloaded |
| */ |
| ctx->ctx_state = PFM_CTX_UNLOADED; |
| |
| /* |
| * initialization of context's flags |
| */ |
| ctx->ctx_fl_block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0; |
| ctx->ctx_fl_system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0; |
| ctx->ctx_fl_is_sampling = ctx->ctx_buf_fmt ? 1 : 0; /* assume record() is defined */ |
| ctx->ctx_fl_no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0; |
| /* |
| * will move to set properties |
| * ctx->ctx_fl_excl_idle = (ctx_flags & PFM_FL_EXCL_IDLE) ? 1: 0; |
| */ |
| |
| /* |
| * init restart semaphore to locked |
| */ |
| sema_init(&ctx->ctx_restart_sem, 0); |
| |
| /* |
| * activation is used in SMP only |
| */ |
| ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; |
| SET_LAST_CPU(ctx, -1); |
| |
| /* |
| * initialize notification message queue |
| */ |
| ctx->ctx_msgq_head = ctx->ctx_msgq_tail = 0; |
| init_waitqueue_head(&ctx->ctx_msgq_wait); |
| init_waitqueue_head(&ctx->ctx_zombieq); |
| |
| DPRINT(("ctx=%p flags=0x%x system=%d notify_block=%d excl_idle=%d no_msg=%d ctx_fd=%d \n", |
| ctx, |
| ctx_flags, |
| ctx->ctx_fl_system, |
| ctx->ctx_fl_block, |
| ctx->ctx_fl_excl_idle, |
| ctx->ctx_fl_no_msg, |
| ctx->ctx_fd)); |
| |
| /* |
| * initialize soft PMU state |
| */ |
| pfm_reset_pmu_state(ctx); |
| |
| return 0; |
| |
| buffer_error: |
| pfm_free_fd(ctx->ctx_fd, filp); |
| |
| if (ctx->ctx_buf_fmt) { |
| pfm_buf_fmt_exit(ctx->ctx_buf_fmt, current, NULL, regs); |
| } |
| error_file: |
| pfm_context_free(ctx); |
| |
| error: |
| return ret; |
| } |
| |
| static inline unsigned long |
| pfm_new_counter_value (pfm_counter_t *reg, int is_long_reset) |
| { |
| unsigned long val = is_long_reset ? reg->long_reset : reg->short_reset; |
| unsigned long new_seed, old_seed = reg->seed, mask = reg->mask; |
| extern unsigned long carta_random32 (unsigned long seed); |
| |
| if (reg->flags & PFM_REGFL_RANDOM) { |
| new_seed = carta_random32(old_seed); |
| val -= (old_seed & mask); /* counter values are negative numbers! */ |
| if ((mask >> 32) != 0) |
| /* construct a full 64-bit random value: */ |
| new_seed |= carta_random32(old_seed >> 32) << 32; |
| reg->seed = new_seed; |
| } |
| reg->lval = val; |
| return val; |
| } |
| |
| static void |
| pfm_reset_regs_masked(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset) |
| { |
| unsigned long mask = ovfl_regs[0]; |
| unsigned long reset_others = 0UL; |
| unsigned long val; |
| int i; |
| |
| /* |
| * now restore reset value on sampling overflowed counters |
| */ |
| mask >>= PMU_FIRST_COUNTER; |
| for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) { |
| |
| if ((mask & 0x1UL) == 0UL) continue; |
| |
| ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset); |
| reset_others |= ctx->ctx_pmds[i].reset_pmds[0]; |
| |
| DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val)); |
| } |
| |
| /* |
| * Now take care of resetting the other registers |
| */ |
| for(i = 0; reset_others; i++, reset_others >>= 1) { |
| |
| if ((reset_others & 0x1) == 0) continue; |
| |
| ctx->ctx_pmds[i].val = val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset); |
| |
| DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n", |
| is_long_reset ? "long" : "short", i, val)); |
| } |
| } |
| |
| static void |
| pfm_reset_regs(pfm_context_t *ctx, unsigned long *ovfl_regs, int is_long_reset) |
| { |
| unsigned long mask = ovfl_regs[0]; |
| unsigned long reset_others = 0UL; |
| unsigned long val; |
| int i; |
| |
| DPRINT_ovfl(("ovfl_regs=0x%lx is_long_reset=%d\n", ovfl_regs[0], is_long_reset)); |
| |
| if (ctx->ctx_state == PFM_CTX_MASKED) { |
| pfm_reset_regs_masked(ctx, ovfl_regs, is_long_reset); |
| return; |
| } |
| |
| /* |
| * now restore reset value on sampling overflowed counters |
| */ |
| mask >>= PMU_FIRST_COUNTER; |
| for(i = PMU_FIRST_COUNTER; mask; i++, mask >>= 1) { |
| |
| if ((mask & 0x1UL) == 0UL) continue; |
| |
| val = pfm_new_counter_value(ctx->ctx_pmds+ i, is_long_reset); |
| reset_others |= ctx->ctx_pmds[i].reset_pmds[0]; |
| |
| DPRINT_ovfl((" %s reset ctx_pmds[%d]=%lx\n", is_long_reset ? "long" : "short", i, val)); |
| |
| pfm_write_soft_counter(ctx, i, val); |
| } |
| |
| /* |
| * Now take care of resetting the other registers |
| */ |
| for(i = 0; reset_others; i++, reset_others >>= 1) { |
| |
| if ((reset_others & 0x1) == 0) continue; |
| |
| val = pfm_new_counter_value(ctx->ctx_pmds + i, is_long_reset); |
| |
| if (PMD_IS_COUNTING(i)) { |
| pfm_write_soft_counter(ctx, i, val); |
| } else { |
| ia64_set_pmd(i, val); |
| } |
| DPRINT_ovfl(("%s reset_others pmd[%d]=%lx\n", |
| is_long_reset ? "long" : "short", i, val)); |
| } |
| ia64_srlz_d(); |
| } |
| |
| static int |
| pfm_write_pmcs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct thread_struct *thread = NULL; |
| struct task_struct *task; |
| pfarg_reg_t *req = (pfarg_reg_t *)arg; |
| unsigned long value, pmc_pm; |
| unsigned long smpl_pmds, reset_pmds, impl_pmds; |
| unsigned int cnum, reg_flags, flags, pmc_type; |
| int i, can_access_pmu = 0, is_loaded, is_system, expert_mode; |
| int is_monitor, is_counting, state; |
| int ret = -EINVAL; |
| pfm_reg_check_t wr_func; |
| #define PFM_CHECK_PMC_PM(x, y, z) ((x)->ctx_fl_system ^ PMC_PM(y, z)) |
| |
| state = ctx->ctx_state; |
| is_loaded = state == PFM_CTX_LOADED ? 1 : 0; |
| is_system = ctx->ctx_fl_system; |
| task = ctx->ctx_task; |
| impl_pmds = pmu_conf->impl_pmds[0]; |
| |
| if (state == PFM_CTX_ZOMBIE) return -EINVAL; |
| |
| if (is_loaded) { |
| thread = &task->thread; |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (is_system && ctx->ctx_cpu != smp_processor_id()) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; |
| } |
| expert_mode = pfm_sysctl.expert_mode; |
| |
| for (i = 0; i < count; i++, req++) { |
| |
| cnum = req->reg_num; |
| reg_flags = req->reg_flags; |
| value = req->reg_value; |
| smpl_pmds = req->reg_smpl_pmds[0]; |
| reset_pmds = req->reg_reset_pmds[0]; |
| flags = 0; |
| |
| |
| if (cnum >= PMU_MAX_PMCS) { |
| DPRINT(("pmc%u is invalid\n", cnum)); |
| goto error; |
| } |
| |
| pmc_type = pmu_conf->pmc_desc[cnum].type; |
| pmc_pm = (value >> pmu_conf->pmc_desc[cnum].pm_pos) & 0x1; |
| is_counting = (pmc_type & PFM_REG_COUNTING) == PFM_REG_COUNTING ? 1 : 0; |
| is_monitor = (pmc_type & PFM_REG_MONITOR) == PFM_REG_MONITOR ? 1 : 0; |
| |
| /* |
| * we reject all non implemented PMC as well |
| * as attempts to modify PMC[0-3] which are used |
| * as status registers by the PMU |
| */ |
| if ((pmc_type & PFM_REG_IMPL) == 0 || (pmc_type & PFM_REG_CONTROL) == PFM_REG_CONTROL) { |
| DPRINT(("pmc%u is unimplemented or no-access pmc_type=%x\n", cnum, pmc_type)); |
| goto error; |
| } |
| wr_func = pmu_conf->pmc_desc[cnum].write_check; |
| /* |
| * If the PMC is a monitor, then if the value is not the default: |
| * - system-wide session: PMCx.pm=1 (privileged monitor) |
| * - per-task : PMCx.pm=0 (user monitor) |
| */ |
| if (is_monitor && value != PMC_DFL_VAL(cnum) && is_system ^ pmc_pm) { |
| DPRINT(("pmc%u pmc_pm=%lu is_system=%d\n", |
| cnum, |
| pmc_pm, |
| is_system)); |
| goto error; |
| } |
| |
| if (is_counting) { |
| /* |
| * enforce generation of overflow interrupt. Necessary on all |
| * CPUs. |
| */ |
| value |= 1 << PMU_PMC_OI; |
| |
| if (reg_flags & PFM_REGFL_OVFL_NOTIFY) { |
| flags |= PFM_REGFL_OVFL_NOTIFY; |
| } |
| |
| if (reg_flags & PFM_REGFL_RANDOM) flags |= PFM_REGFL_RANDOM; |
| |
| /* verify validity of smpl_pmds */ |
| if ((smpl_pmds & impl_pmds) != smpl_pmds) { |
| DPRINT(("invalid smpl_pmds 0x%lx for pmc%u\n", smpl_pmds, cnum)); |
| goto error; |
| } |
| |
| /* verify validity of reset_pmds */ |
| if ((reset_pmds & impl_pmds) != reset_pmds) { |
| DPRINT(("invalid reset_pmds 0x%lx for pmc%u\n", reset_pmds, cnum)); |
| goto error; |
| } |
| } else { |
| if (reg_flags & (PFM_REGFL_OVFL_NOTIFY|PFM_REGFL_RANDOM)) { |
| DPRINT(("cannot set ovfl_notify or random on pmc%u\n", cnum)); |
| goto error; |
| } |
| /* eventid on non-counting monitors are ignored */ |
| } |
| |
| /* |
| * execute write checker, if any |
| */ |
| if (likely(expert_mode == 0 && wr_func)) { |
| ret = (*wr_func)(task, ctx, cnum, &value, regs); |
| if (ret) goto error; |
| ret = -EINVAL; |
| } |
| |
| /* |
| * no error on this register |
| */ |
| PFM_REG_RETFLAG_SET(req->reg_flags, 0); |
| |
| /* |
| * Now we commit the changes to the software state |
| */ |
| |
| /* |
| * update overflow information |
| */ |
| if (is_counting) { |
| /* |
| * full flag update each time a register is programmed |
| */ |
| ctx->ctx_pmds[cnum].flags = flags; |
| |
| ctx->ctx_pmds[cnum].reset_pmds[0] = reset_pmds; |
| ctx->ctx_pmds[cnum].smpl_pmds[0] = smpl_pmds; |
| ctx->ctx_pmds[cnum].eventid = req->reg_smpl_eventid; |
| |
| /* |
| * Mark all PMDS to be accessed as used. |
| * |
| * We do not keep track of PMC because we have to |
| * systematically restore ALL of them. |
| * |
| * We do not update the used_monitors mask, because |
| * if we have not programmed them, then will be in |
| * a quiescent state, therefore we will not need to |
| * mask/restore then when context is MASKED. |
| */ |
| CTX_USED_PMD(ctx, reset_pmds); |
| CTX_USED_PMD(ctx, smpl_pmds); |
| /* |
| * make sure we do not try to reset on |
| * restart because we have established new values |
| */ |
| if (state == PFM_CTX_MASKED) ctx->ctx_ovfl_regs[0] &= ~1UL << cnum; |
| } |
| /* |
| * Needed in case the user does not initialize the equivalent |
| * PMD. Clearing is done indirectly via pfm_reset_pmu_state() so there is no |
| * possible leak here. |
| */ |
| CTX_USED_PMD(ctx, pmu_conf->pmc_desc[cnum].dep_pmd[0]); |
| |
| /* |
| * keep track of the monitor PMC that we are using. |
| * we save the value of the pmc in ctx_pmcs[] and if |
| * the monitoring is not stopped for the context we also |
| * place it in the saved state area so that it will be |
| * picked up later by the context switch code. |
| * |
| * The value in ctx_pmcs[] can only be changed in pfm_write_pmcs(). |
| * |
| * The value in thread->pmcs[] may be modified on overflow, i.e., when |
| * monitoring needs to be stopped. |
| */ |
| if (is_monitor) CTX_USED_MONITOR(ctx, 1UL << cnum); |
| |
| /* |
| * update context state |
| */ |
| ctx->ctx_pmcs[cnum] = value; |
| |
| if (is_loaded) { |
| /* |
| * write thread state |
| */ |
| if (is_system == 0) thread->pmcs[cnum] = value; |
| |
| /* |
| * write hardware register if we can |
| */ |
| if (can_access_pmu) { |
| ia64_set_pmc(cnum, value); |
| } |
| #ifdef CONFIG_SMP |
| else { |
| /* |
| * per-task SMP only here |
| * |
| * we are guaranteed that the task is not running on the other CPU, |
| * we indicate that this PMD will need to be reloaded if the task |
| * is rescheduled on the CPU it ran last on. |
| */ |
| ctx->ctx_reload_pmcs[0] |= 1UL << cnum; |
| } |
| #endif |
| } |
| |
| DPRINT(("pmc[%u]=0x%lx ld=%d apmu=%d flags=0x%x all_pmcs=0x%lx used_pmds=0x%lx eventid=%ld smpl_pmds=0x%lx reset_pmds=0x%lx reloads_pmcs=0x%lx used_monitors=0x%lx ovfl_regs=0x%lx\n", |
| cnum, |
| value, |
| is_loaded, |
| can_access_pmu, |
| flags, |
| ctx->ctx_all_pmcs[0], |
| ctx->ctx_used_pmds[0], |
| ctx->ctx_pmds[cnum].eventid, |
| smpl_pmds, |
| reset_pmds, |
| ctx->ctx_reload_pmcs[0], |
| ctx->ctx_used_monitors[0], |
| ctx->ctx_ovfl_regs[0])); |
| } |
| |
| /* |
| * make sure the changes are visible |
| */ |
| if (can_access_pmu) ia64_srlz_d(); |
| |
| return 0; |
| error: |
| PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); |
| return ret; |
| } |
| |
| static int |
| pfm_write_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct thread_struct *thread = NULL; |
| struct task_struct *task; |
| pfarg_reg_t *req = (pfarg_reg_t *)arg; |
| unsigned long value, hw_value, ovfl_mask; |
| unsigned int cnum; |
| int i, can_access_pmu = 0, state; |
| int is_counting, is_loaded, is_system, expert_mode; |
| int ret = -EINVAL; |
| pfm_reg_check_t wr_func; |
| |
| |
| state = ctx->ctx_state; |
| is_loaded = state == PFM_CTX_LOADED ? 1 : 0; |
| is_system = ctx->ctx_fl_system; |
| ovfl_mask = pmu_conf->ovfl_val; |
| task = ctx->ctx_task; |
| |
| if (unlikely(state == PFM_CTX_ZOMBIE)) return -EINVAL; |
| |
| /* |
| * on both UP and SMP, we can only write to the PMC when the task is |
| * the owner of the local PMU. |
| */ |
| if (likely(is_loaded)) { |
| thread = &task->thread; |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; |
| } |
| expert_mode = pfm_sysctl.expert_mode; |
| |
| for (i = 0; i < count; i++, req++) { |
| |
| cnum = req->reg_num; |
| value = req->reg_value; |
| |
| if (!PMD_IS_IMPL(cnum)) { |
| DPRINT(("pmd[%u] is unimplemented or invalid\n", cnum)); |
| goto abort_mission; |
| } |
| is_counting = PMD_IS_COUNTING(cnum); |
| wr_func = pmu_conf->pmd_desc[cnum].write_check; |
| |
| /* |
| * execute write checker, if any |
| */ |
| if (unlikely(expert_mode == 0 && wr_func)) { |
| unsigned long v = value; |
| |
| ret = (*wr_func)(task, ctx, cnum, &v, regs); |
| if (ret) goto abort_mission; |
| |
| value = v; |
| ret = -EINVAL; |
| } |
| |
| /* |
| * no error on this register |
| */ |
| PFM_REG_RETFLAG_SET(req->reg_flags, 0); |
| |
| /* |
| * now commit changes to software state |
| */ |
| hw_value = value; |
| |
| /* |
| * update virtualized (64bits) counter |
| */ |
| if (is_counting) { |
| /* |
| * write context state |
| */ |
| ctx->ctx_pmds[cnum].lval = value; |
| |
| /* |
| * when context is load we use the split value |
| */ |
| if (is_loaded) { |
| hw_value = value & ovfl_mask; |
| value = value & ~ovfl_mask; |
| } |
| } |
| /* |
| * update reset values (not just for counters) |
| */ |
| ctx->ctx_pmds[cnum].long_reset = req->reg_long_reset; |
| ctx->ctx_pmds[cnum].short_reset = req->reg_short_reset; |
| |
| /* |
| * update randomization parameters (not just for counters) |
| */ |
| ctx->ctx_pmds[cnum].seed = req->reg_random_seed; |
| ctx->ctx_pmds[cnum].mask = req->reg_random_mask; |
| |
| /* |
| * update context value |
| */ |
| ctx->ctx_pmds[cnum].val = value; |
| |
| /* |
| * Keep track of what we use |
| * |
| * We do not keep track of PMC because we have to |
| * systematically restore ALL of them. |
| */ |
| CTX_USED_PMD(ctx, PMD_PMD_DEP(cnum)); |
| |
| /* |
| * mark this PMD register used as well |
| */ |
| CTX_USED_PMD(ctx, RDEP(cnum)); |
| |
| /* |
| * make sure we do not try to reset on |
| * restart because we have established new values |
| */ |
| if (is_counting && state == PFM_CTX_MASKED) { |
| ctx->ctx_ovfl_regs[0] &= ~1UL << cnum; |
| } |
| |
| if (is_loaded) { |
| /* |
| * write thread state |
| */ |
| if (is_system == 0) thread->pmds[cnum] = hw_value; |
| |
| /* |
| * write hardware register if we can |
| */ |
| if (can_access_pmu) { |
| ia64_set_pmd(cnum, hw_value); |
| } else { |
| #ifdef CONFIG_SMP |
| /* |
| * we are guaranteed that the task is not running on the other CPU, |
| * we indicate that this PMD will need to be reloaded if the task |
| * is rescheduled on the CPU it ran last on. |
| */ |
| ctx->ctx_reload_pmds[0] |= 1UL << cnum; |
| #endif |
| } |
| } |
| |
| DPRINT(("pmd[%u]=0x%lx ld=%d apmu=%d, hw_value=0x%lx ctx_pmd=0x%lx short_reset=0x%lx " |
| "long_reset=0x%lx notify=%c seed=0x%lx mask=0x%lx used_pmds=0x%lx reset_pmds=0x%lx reload_pmds=0x%lx all_pmds=0x%lx ovfl_regs=0x%lx\n", |
| cnum, |
| value, |
| is_loaded, |
| can_access_pmu, |
| hw_value, |
| ctx->ctx_pmds[cnum].val, |
| ctx->ctx_pmds[cnum].short_reset, |
| ctx->ctx_pmds[cnum].long_reset, |
| PMC_OVFL_NOTIFY(ctx, cnum) ? 'Y':'N', |
| ctx->ctx_pmds[cnum].seed, |
| ctx->ctx_pmds[cnum].mask, |
| ctx->ctx_used_pmds[0], |
| ctx->ctx_pmds[cnum].reset_pmds[0], |
| ctx->ctx_reload_pmds[0], |
| ctx->ctx_all_pmds[0], |
| ctx->ctx_ovfl_regs[0])); |
| } |
| |
| /* |
| * make changes visible |
| */ |
| if (can_access_pmu) ia64_srlz_d(); |
| |
| return 0; |
| |
| abort_mission: |
| /* |
| * for now, we have only one possibility for error |
| */ |
| PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); |
| return ret; |
| } |
| |
| /* |
| * By the way of PROTECT_CONTEXT(), interrupts are masked while we are in this function. |
| * Therefore we know, we do not have to worry about the PMU overflow interrupt. If an |
| * interrupt is delivered during the call, it will be kept pending until we leave, making |
| * it appears as if it had been generated at the UNPROTECT_CONTEXT(). At least we are |
| * guaranteed to return consistent data to the user, it may simply be old. It is not |
| * trivial to treat the overflow while inside the call because you may end up in |
| * some module sampling buffer code causing deadlocks. |
| */ |
| static int |
| pfm_read_pmds(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct thread_struct *thread = NULL; |
| struct task_struct *task; |
| unsigned long val = 0UL, lval, ovfl_mask, sval; |
| pfarg_reg_t *req = (pfarg_reg_t *)arg; |
| unsigned int cnum, reg_flags = 0; |
| int i, can_access_pmu = 0, state; |
| int is_loaded, is_system, is_counting, expert_mode; |
| int ret = -EINVAL; |
| pfm_reg_check_t rd_func; |
| |
| /* |
| * access is possible when loaded only for |
| * self-monitoring tasks or in UP mode |
| */ |
| |
| state = ctx->ctx_state; |
| is_loaded = state == PFM_CTX_LOADED ? 1 : 0; |
| is_system = ctx->ctx_fl_system; |
| ovfl_mask = pmu_conf->ovfl_val; |
| task = ctx->ctx_task; |
| |
| if (state == PFM_CTX_ZOMBIE) return -EINVAL; |
| |
| if (likely(is_loaded)) { |
| thread = &task->thread; |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| /* |
| * this can be true when not self-monitoring only in UP |
| */ |
| can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; |
| |
| if (can_access_pmu) ia64_srlz_d(); |
| } |
| expert_mode = pfm_sysctl.expert_mode; |
| |
| DPRINT(("ld=%d apmu=%d ctx_state=%d\n", |
| is_loaded, |
| can_access_pmu, |
| state)); |
| |
| /* |
| * on both UP and SMP, we can only read the PMD from the hardware register when |
| * the task is the owner of the local PMU. |
| */ |
| |
| for (i = 0; i < count; i++, req++) { |
| |
| cnum = req->reg_num; |
| reg_flags = req->reg_flags; |
| |
| if (unlikely(!PMD_IS_IMPL(cnum))) goto error; |
| /* |
| * we can only read the register that we use. That includes |
| * the one we explicitely initialize AND the one we want included |
| * in the sampling buffer (smpl_regs). |
| * |
| * Having this restriction allows optimization in the ctxsw routine |
| * without compromising security (leaks) |
| */ |
| if (unlikely(!CTX_IS_USED_PMD(ctx, cnum))) goto error; |
| |
| sval = ctx->ctx_pmds[cnum].val; |
| lval = ctx->ctx_pmds[cnum].lval; |
| is_counting = PMD_IS_COUNTING(cnum); |
| |
| /* |
| * If the task is not the current one, then we check if the |
| * PMU state is still in the local live register due to lazy ctxsw. |
| * If true, then we read directly from the registers. |
| */ |
| if (can_access_pmu){ |
| val = ia64_get_pmd(cnum); |
| } else { |
| /* |
| * context has been saved |
| * if context is zombie, then task does not exist anymore. |
| * In this case, we use the full value saved in the context (pfm_flush_regs()). |
| */ |
| val = is_loaded ? thread->pmds[cnum] : 0UL; |
| } |
| rd_func = pmu_conf->pmd_desc[cnum].read_check; |
| |
| if (is_counting) { |
| /* |
| * XXX: need to check for overflow when loaded |
| */ |
| val &= ovfl_mask; |
| val += sval; |
| } |
| |
| /* |
| * execute read checker, if any |
| */ |
| if (unlikely(expert_mode == 0 && rd_func)) { |
| unsigned long v = val; |
| ret = (*rd_func)(ctx->ctx_task, ctx, cnum, &v, regs); |
| if (ret) goto error; |
| val = v; |
| ret = -EINVAL; |
| } |
| |
| PFM_REG_RETFLAG_SET(reg_flags, 0); |
| |
| DPRINT(("pmd[%u]=0x%lx\n", cnum, val)); |
| |
| /* |
| * update register return value, abort all if problem during copy. |
| * we only modify the reg_flags field. no check mode is fine because |
| * access has been verified upfront in sys_perfmonctl(). |
| */ |
| req->reg_value = val; |
| req->reg_flags = reg_flags; |
| req->reg_last_reset_val = lval; |
| } |
| |
| return 0; |
| |
| error: |
| PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); |
| return ret; |
| } |
| |
| int |
| pfm_mod_write_pmcs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) |
| { |
| pfm_context_t *ctx; |
| |
| if (req == NULL) return -EINVAL; |
| |
| ctx = GET_PMU_CTX(); |
| |
| if (ctx == NULL) return -EINVAL; |
| |
| /* |
| * for now limit to current task, which is enough when calling |
| * from overflow handler |
| */ |
| if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; |
| |
| return pfm_write_pmcs(ctx, req, nreq, regs); |
| } |
| EXPORT_SYMBOL(pfm_mod_write_pmcs); |
| |
| int |
| pfm_mod_read_pmds(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) |
| { |
| pfm_context_t *ctx; |
| |
| if (req == NULL) return -EINVAL; |
| |
| ctx = GET_PMU_CTX(); |
| |
| if (ctx == NULL) return -EINVAL; |
| |
| /* |
| * for now limit to current task, which is enough when calling |
| * from overflow handler |
| */ |
| if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; |
| |
| return pfm_read_pmds(ctx, req, nreq, regs); |
| } |
| EXPORT_SYMBOL(pfm_mod_read_pmds); |
| |
| /* |
| * Only call this function when a process it trying to |
| * write the debug registers (reading is always allowed) |
| */ |
| int |
| pfm_use_debug_registers(struct task_struct *task) |
| { |
| pfm_context_t *ctx = task->thread.pfm_context; |
| unsigned long flags; |
| int ret = 0; |
| |
| if (pmu_conf->use_rr_dbregs == 0) return 0; |
| |
| DPRINT(("called for [%d]\n", task->pid)); |
| |
| /* |
| * do it only once |
| */ |
| if (task->thread.flags & IA64_THREAD_DBG_VALID) return 0; |
| |
| /* |
| * Even on SMP, we do not need to use an atomic here because |
| * the only way in is via ptrace() and this is possible only when the |
| * process is stopped. Even in the case where the ctxsw out is not totally |
| * completed by the time we come here, there is no way the 'stopped' process |
| * could be in the middle of fiddling with the pfm_write_ibr_dbr() routine. |
| * So this is always safe. |
| */ |
| if (ctx && ctx->ctx_fl_using_dbreg == 1) return -1; |
| |
| LOCK_PFS(flags); |
| |
| /* |
| * We cannot allow setting breakpoints when system wide monitoring |
| * sessions are using the debug registers. |
| */ |
| if (pfm_sessions.pfs_sys_use_dbregs> 0) |
| ret = -1; |
| else |
| pfm_sessions.pfs_ptrace_use_dbregs++; |
| |
| DPRINT(("ptrace_use_dbregs=%u sys_use_dbregs=%u by [%d] ret = %d\n", |
| pfm_sessions.pfs_ptrace_use_dbregs, |
| pfm_sessions.pfs_sys_use_dbregs, |
| task->pid, ret)); |
| |
| UNLOCK_PFS(flags); |
| |
| return ret; |
| } |
| |
| /* |
| * This function is called for every task that exits with the |
| * IA64_THREAD_DBG_VALID set. This indicates a task which was |
| * able to use the debug registers for debugging purposes via |
| * ptrace(). Therefore we know it was not using them for |
| * perfmormance monitoring, so we only decrement the number |
| * of "ptraced" debug register users to keep the count up to date |
| */ |
| int |
| pfm_release_debug_registers(struct task_struct *task) |
| { |
| unsigned long flags; |
| int ret; |
| |
| if (pmu_conf->use_rr_dbregs == 0) return 0; |
| |
| LOCK_PFS(flags); |
| if (pfm_sessions.pfs_ptrace_use_dbregs == 0) { |
| printk(KERN_ERR "perfmon: invalid release for [%d] ptrace_use_dbregs=0\n", task->pid); |
| ret = -1; |
| } else { |
| pfm_sessions.pfs_ptrace_use_dbregs--; |
| ret = 0; |
| } |
| UNLOCK_PFS(flags); |
| |
| return ret; |
| } |
| |
| static int |
| pfm_restart(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct task_struct *task; |
| pfm_buffer_fmt_t *fmt; |
| pfm_ovfl_ctrl_t rst_ctrl; |
| int state, is_system; |
| int ret = 0; |
| |
| state = ctx->ctx_state; |
| fmt = ctx->ctx_buf_fmt; |
| is_system = ctx->ctx_fl_system; |
| task = PFM_CTX_TASK(ctx); |
| |
| switch(state) { |
| case PFM_CTX_MASKED: |
| break; |
| case PFM_CTX_LOADED: |
| if (CTX_HAS_SMPL(ctx) && fmt->fmt_restart_active) break; |
| /* fall through */ |
| case PFM_CTX_UNLOADED: |
| case PFM_CTX_ZOMBIE: |
| DPRINT(("invalid state=%d\n", state)); |
| return -EBUSY; |
| default: |
| DPRINT(("state=%d, cannot operate (no active_restart handler)\n", state)); |
| return -EINVAL; |
| } |
| |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (is_system && ctx->ctx_cpu != smp_processor_id()) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| |
| /* sanity check */ |
| if (unlikely(task == NULL)) { |
| printk(KERN_ERR "perfmon: [%d] pfm_restart no task\n", current->pid); |
| return -EINVAL; |
| } |
| |
| if (task == current || is_system) { |
| |
| fmt = ctx->ctx_buf_fmt; |
| |
| DPRINT(("restarting self %d ovfl=0x%lx\n", |
| task->pid, |
| ctx->ctx_ovfl_regs[0])); |
| |
| if (CTX_HAS_SMPL(ctx)) { |
| |
| prefetch(ctx->ctx_smpl_hdr); |
| |
| rst_ctrl.bits.mask_monitoring = 0; |
| rst_ctrl.bits.reset_ovfl_pmds = 0; |
| |
| if (state == PFM_CTX_LOADED) |
| ret = pfm_buf_fmt_restart_active(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs); |
| else |
| ret = pfm_buf_fmt_restart(fmt, task, &rst_ctrl, ctx->ctx_smpl_hdr, regs); |
| } else { |
| rst_ctrl.bits.mask_monitoring = 0; |
| rst_ctrl.bits.reset_ovfl_pmds = 1; |
| } |
| |
| if (ret == 0) { |
| if (rst_ctrl.bits.reset_ovfl_pmds) |
| pfm_reset_regs(ctx, ctx->ctx_ovfl_regs, PFM_PMD_LONG_RESET); |
| |
| if (rst_ctrl.bits.mask_monitoring == 0) { |
| DPRINT(("resuming monitoring for [%d]\n", task->pid)); |
| |
| if (state == PFM_CTX_MASKED) pfm_restore_monitoring(task); |
| } else { |
| DPRINT(("keeping monitoring stopped for [%d]\n", task->pid)); |
| |
| // cannot use pfm_stop_monitoring(task, regs); |
| } |
| } |
| /* |
| * clear overflowed PMD mask to remove any stale information |
| */ |
| ctx->ctx_ovfl_regs[0] = 0UL; |
| |
| /* |
| * back to LOADED state |
| */ |
| ctx->ctx_state = PFM_CTX_LOADED; |
| |
| /* |
| * XXX: not really useful for self monitoring |
| */ |
| ctx->ctx_fl_can_restart = 0; |
| |
| return 0; |
| } |
| |
| /* |
| * restart another task |
| */ |
| |
| /* |
| * When PFM_CTX_MASKED, we cannot issue a restart before the previous |
| * one is seen by the task. |
| */ |
| if (state == PFM_CTX_MASKED) { |
| if (ctx->ctx_fl_can_restart == 0) return -EINVAL; |
| /* |
| * will prevent subsequent restart before this one is |
| * seen by other task |
| */ |
| ctx->ctx_fl_can_restart = 0; |
| } |
| |
| /* |
| * if blocking, then post the semaphore is PFM_CTX_MASKED, i.e. |
| * the task is blocked or on its way to block. That's the normal |
| * restart path. If the monitoring is not masked, then the task |
| * can be actively monitoring and we cannot directly intervene. |
| * Therefore we use the trap mechanism to catch the task and |
| * force it to reset the buffer/reset PMDs. |
| * |
| * if non-blocking, then we ensure that the task will go into |
| * pfm_handle_work() before returning to user mode. |
| * |
| * We cannot explicitely reset another task, it MUST always |
| * be done by the task itself. This works for system wide because |
| * the tool that is controlling the session is logically doing |
| * "self-monitoring". |
| */ |
| if (CTX_OVFL_NOBLOCK(ctx) == 0 && state == PFM_CTX_MASKED) { |
| DPRINT(("unblocking [%d] \n", task->pid)); |
| up(&ctx->ctx_restart_sem); |
| } else { |
| DPRINT(("[%d] armed exit trap\n", task->pid)); |
| |
| ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_RESET; |
| |
| PFM_SET_WORK_PENDING(task, 1); |
| |
| pfm_set_task_notify(task); |
| |
| /* |
| * XXX: send reschedule if task runs on another CPU |
| */ |
| } |
| return 0; |
| } |
| |
| static int |
| pfm_debug(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| unsigned int m = *(unsigned int *)arg; |
| |
| pfm_sysctl.debug = m == 0 ? 0 : 1; |
| |
| printk(KERN_INFO "perfmon debugging %s (timing reset)\n", pfm_sysctl.debug ? "on" : "off"); |
| |
| if (m == 0) { |
| memset(pfm_stats, 0, sizeof(pfm_stats)); |
| for(m=0; m < NR_CPUS; m++) pfm_stats[m].pfm_ovfl_intr_cycles_min = ~0UL; |
| } |
| return 0; |
| } |
| |
| /* |
| * arg can be NULL and count can be zero for this function |
| */ |
| static int |
| pfm_write_ibr_dbr(int mode, pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct thread_struct *thread = NULL; |
| struct task_struct *task; |
| pfarg_dbreg_t *req = (pfarg_dbreg_t *)arg; |
| unsigned long flags; |
| dbreg_t dbreg; |
| unsigned int rnum; |
| int first_time; |
| int ret = 0, state; |
| int i, can_access_pmu = 0; |
| int is_system, is_loaded; |
| |
| if (pmu_conf->use_rr_dbregs == 0) return -EINVAL; |
| |
| state = ctx->ctx_state; |
| is_loaded = state == PFM_CTX_LOADED ? 1 : 0; |
| is_system = ctx->ctx_fl_system; |
| task = ctx->ctx_task; |
| |
| if (state == PFM_CTX_ZOMBIE) return -EINVAL; |
| |
| /* |
| * on both UP and SMP, we can only write to the PMC when the task is |
| * the owner of the local PMU. |
| */ |
| if (is_loaded) { |
| thread = &task->thread; |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (unlikely(is_system && ctx->ctx_cpu != smp_processor_id())) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| can_access_pmu = GET_PMU_OWNER() == task || is_system ? 1 : 0; |
| } |
| |
| /* |
| * we do not need to check for ipsr.db because we do clear ibr.x, dbr.r, and dbr.w |
| * ensuring that no real breakpoint can be installed via this call. |
| * |
| * IMPORTANT: regs can be NULL in this function |
| */ |
| |
| first_time = ctx->ctx_fl_using_dbreg == 0; |
| |
| /* |
| * don't bother if we are loaded and task is being debugged |
| */ |
| if (is_loaded && (thread->flags & IA64_THREAD_DBG_VALID) != 0) { |
| DPRINT(("debug registers already in use for [%d]\n", task->pid)); |
| return -EBUSY; |
| } |
| |
| /* |
| * check for debug registers in system wide mode |
| * |
| * If though a check is done in pfm_context_load(), |
| * we must repeat it here, in case the registers are |
| * written after the context is loaded |
| */ |
| if (is_loaded) { |
| LOCK_PFS(flags); |
| |
| if (first_time && is_system) { |
| if (pfm_sessions.pfs_ptrace_use_dbregs) |
| ret = -EBUSY; |
| else |
| pfm_sessions.pfs_sys_use_dbregs++; |
| } |
| UNLOCK_PFS(flags); |
| } |
| |
| if (ret != 0) return ret; |
| |
| /* |
| * mark ourself as user of the debug registers for |
| * perfmon purposes. |
| */ |
| ctx->ctx_fl_using_dbreg = 1; |
| |
| /* |
| * clear hardware registers to make sure we don't |
| * pick up stale state. |
| * |
| * for a system wide session, we do not use |
| * thread.dbr, thread.ibr because this process |
| * never leaves the current CPU and the state |
| * is shared by all processes running on it |
| */ |
| if (first_time && can_access_pmu) { |
| DPRINT(("[%d] clearing ibrs, dbrs\n", task->pid)); |
| for (i=0; i < pmu_conf->num_ibrs; i++) { |
| ia64_set_ibr(i, 0UL); |
| ia64_dv_serialize_instruction(); |
| } |
| ia64_srlz_i(); |
| for (i=0; i < pmu_conf->num_dbrs; i++) { |
| ia64_set_dbr(i, 0UL); |
| ia64_dv_serialize_data(); |
| } |
| ia64_srlz_d(); |
| } |
| |
| /* |
| * Now install the values into the registers |
| */ |
| for (i = 0; i < count; i++, req++) { |
| |
| rnum = req->dbreg_num; |
| dbreg.val = req->dbreg_value; |
| |
| ret = -EINVAL; |
| |
| if ((mode == PFM_CODE_RR && rnum >= PFM_NUM_IBRS) || ((mode == PFM_DATA_RR) && rnum >= PFM_NUM_DBRS)) { |
| DPRINT(("invalid register %u val=0x%lx mode=%d i=%d count=%d\n", |
| rnum, dbreg.val, mode, i, count)); |
| |
| goto abort_mission; |
| } |
| |
| /* |
| * make sure we do not install enabled breakpoint |
| */ |
| if (rnum & 0x1) { |
| if (mode == PFM_CODE_RR) |
| dbreg.ibr.ibr_x = 0; |
| else |
| dbreg.dbr.dbr_r = dbreg.dbr.dbr_w = 0; |
| } |
| |
| PFM_REG_RETFLAG_SET(req->dbreg_flags, 0); |
| |
| /* |
| * Debug registers, just like PMC, can only be modified |
| * by a kernel call. Moreover, perfmon() access to those |
| * registers are centralized in this routine. The hardware |
| * does not modify the value of these registers, therefore, |
| * if we save them as they are written, we can avoid having |
| * to save them on context switch out. This is made possible |
| * by the fact that when perfmon uses debug registers, ptrace() |
| * won't be able to modify them concurrently. |
| */ |
| if (mode == PFM_CODE_RR) { |
| CTX_USED_IBR(ctx, rnum); |
| |
| if (can_access_pmu) { |
| ia64_set_ibr(rnum, dbreg.val); |
| ia64_dv_serialize_instruction(); |
| } |
| |
| ctx->ctx_ibrs[rnum] = dbreg.val; |
| |
| DPRINT(("write ibr%u=0x%lx used_ibrs=0x%x ld=%d apmu=%d\n", |
| rnum, dbreg.val, ctx->ctx_used_ibrs[0], is_loaded, can_access_pmu)); |
| } else { |
| CTX_USED_DBR(ctx, rnum); |
| |
| if (can_access_pmu) { |
| ia64_set_dbr(rnum, dbreg.val); |
| ia64_dv_serialize_data(); |
| } |
| ctx->ctx_dbrs[rnum] = dbreg.val; |
| |
| DPRINT(("write dbr%u=0x%lx used_dbrs=0x%x ld=%d apmu=%d\n", |
| rnum, dbreg.val, ctx->ctx_used_dbrs[0], is_loaded, can_access_pmu)); |
| } |
| } |
| |
| return 0; |
| |
| abort_mission: |
| /* |
| * in case it was our first attempt, we undo the global modifications |
| */ |
| if (first_time) { |
| LOCK_PFS(flags); |
| if (ctx->ctx_fl_system) { |
| pfm_sessions.pfs_sys_use_dbregs--; |
| } |
| UNLOCK_PFS(flags); |
| ctx->ctx_fl_using_dbreg = 0; |
| } |
| /* |
| * install error return flag |
| */ |
| PFM_REG_RETFLAG_SET(req->dbreg_flags, PFM_REG_RETFL_EINVAL); |
| |
| return ret; |
| } |
| |
| static int |
| pfm_write_ibrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| return pfm_write_ibr_dbr(PFM_CODE_RR, ctx, arg, count, regs); |
| } |
| |
| static int |
| pfm_write_dbrs(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| return pfm_write_ibr_dbr(PFM_DATA_RR, ctx, arg, count, regs); |
| } |
| |
| int |
| pfm_mod_write_ibrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) |
| { |
| pfm_context_t *ctx; |
| |
| if (req == NULL) return -EINVAL; |
| |
| ctx = GET_PMU_CTX(); |
| |
| if (ctx == NULL) return -EINVAL; |
| |
| /* |
| * for now limit to current task, which is enough when calling |
| * from overflow handler |
| */ |
| if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; |
| |
| return pfm_write_ibrs(ctx, req, nreq, regs); |
| } |
| EXPORT_SYMBOL(pfm_mod_write_ibrs); |
| |
| int |
| pfm_mod_write_dbrs(struct task_struct *task, void *req, unsigned int nreq, struct pt_regs *regs) |
| { |
| pfm_context_t *ctx; |
| |
| if (req == NULL) return -EINVAL; |
| |
| ctx = GET_PMU_CTX(); |
| |
| if (ctx == NULL) return -EINVAL; |
| |
| /* |
| * for now limit to current task, which is enough when calling |
| * from overflow handler |
| */ |
| if (task != current && ctx->ctx_fl_system == 0) return -EBUSY; |
| |
| return pfm_write_dbrs(ctx, req, nreq, regs); |
| } |
| EXPORT_SYMBOL(pfm_mod_write_dbrs); |
| |
| |
| static int |
| pfm_get_features(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| pfarg_features_t *req = (pfarg_features_t *)arg; |
| |
| req->ft_version = PFM_VERSION; |
| return 0; |
| } |
| |
| static int |
| pfm_stop(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct pt_regs *tregs; |
| struct task_struct *task = PFM_CTX_TASK(ctx); |
| int state, is_system; |
| |
| state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| |
| /* |
| * context must be attached to issue the stop command (includes LOADED,MASKED,ZOMBIE) |
| */ |
| if (state == PFM_CTX_UNLOADED) return -EINVAL; |
| |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (is_system && ctx->ctx_cpu != smp_processor_id()) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| DPRINT(("task [%d] ctx_state=%d is_system=%d\n", |
| PFM_CTX_TASK(ctx)->pid, |
| state, |
| is_system)); |
| /* |
| * in system mode, we need to update the PMU directly |
| * and the user level state of the caller, which may not |
| * necessarily be the creator of the context. |
| */ |
| if (is_system) { |
| /* |
| * Update local PMU first |
| * |
| * disable dcr pp |
| */ |
| ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) & ~IA64_DCR_PP); |
| ia64_srlz_i(); |
| |
| /* |
| * update local cpuinfo |
| */ |
| PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP); |
| |
| /* |
| * stop monitoring, does srlz.i |
| */ |
| pfm_clear_psr_pp(); |
| |
| /* |
| * stop monitoring in the caller |
| */ |
| ia64_psr(regs)->pp = 0; |
| |
| return 0; |
| } |
| /* |
| * per-task mode |
| */ |
| |
| if (task == current) { |
| /* stop monitoring at kernel level */ |
| pfm_clear_psr_up(); |
| |
| /* |
| * stop monitoring at the user level |
| */ |
| ia64_psr(regs)->up = 0; |
| } else { |
| tregs = ia64_task_regs(task); |
| |
| /* |
| * stop monitoring at the user level |
| */ |
| ia64_psr(tregs)->up = 0; |
| |
| /* |
| * monitoring disabled in kernel at next reschedule |
| */ |
| ctx->ctx_saved_psr_up = 0; |
| DPRINT(("task=[%d]\n", task->pid)); |
| } |
| return 0; |
| } |
| |
| |
| static int |
| pfm_start(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct pt_regs *tregs; |
| int state, is_system; |
| |
| state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| |
| if (state != PFM_CTX_LOADED) return -EINVAL; |
| |
| /* |
| * In system wide and when the context is loaded, access can only happen |
| * when the caller is running on the CPU being monitored by the session. |
| * It does not have to be the owner (ctx_task) of the context per se. |
| */ |
| if (is_system && ctx->ctx_cpu != smp_processor_id()) { |
| DPRINT(("should be running on CPU%d\n", ctx->ctx_cpu)); |
| return -EBUSY; |
| } |
| |
| /* |
| * in system mode, we need to update the PMU directly |
| * and the user level state of the caller, which may not |
| * necessarily be the creator of the context. |
| */ |
| if (is_system) { |
| |
| /* |
| * set user level psr.pp for the caller |
| */ |
| ia64_psr(regs)->pp = 1; |
| |
| /* |
| * now update the local PMU and cpuinfo |
| */ |
| PFM_CPUINFO_SET(PFM_CPUINFO_DCR_PP); |
| |
| /* |
| * start monitoring at kernel level |
| */ |
| pfm_set_psr_pp(); |
| |
| /* enable dcr pp */ |
| ia64_setreg(_IA64_REG_CR_DCR, ia64_getreg(_IA64_REG_CR_DCR) | IA64_DCR_PP); |
| ia64_srlz_i(); |
| |
| return 0; |
| } |
| |
| /* |
| * per-process mode |
| */ |
| |
| if (ctx->ctx_task == current) { |
| |
| /* start monitoring at kernel level */ |
| pfm_set_psr_up(); |
| |
| /* |
| * activate monitoring at user level |
| */ |
| ia64_psr(regs)->up = 1; |
| |
| } else { |
| tregs = ia64_task_regs(ctx->ctx_task); |
| |
| /* |
| * start monitoring at the kernel level the next |
| * time the task is scheduled |
| */ |
| ctx->ctx_saved_psr_up = IA64_PSR_UP; |
| |
| /* |
| * activate monitoring at user level |
| */ |
| ia64_psr(tregs)->up = 1; |
| } |
| return 0; |
| } |
| |
| static int |
| pfm_get_pmc_reset(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| pfarg_reg_t *req = (pfarg_reg_t *)arg; |
| unsigned int cnum; |
| int i; |
| int ret = -EINVAL; |
| |
| for (i = 0; i < count; i++, req++) { |
| |
| cnum = req->reg_num; |
| |
| if (!PMC_IS_IMPL(cnum)) goto abort_mission; |
| |
| req->reg_value = PMC_DFL_VAL(cnum); |
| |
| PFM_REG_RETFLAG_SET(req->reg_flags, 0); |
| |
| DPRINT(("pmc_reset_val pmc[%u]=0x%lx\n", cnum, req->reg_value)); |
| } |
| return 0; |
| |
| abort_mission: |
| PFM_REG_RETFLAG_SET(req->reg_flags, PFM_REG_RETFL_EINVAL); |
| return ret; |
| } |
| |
| static int |
| pfm_check_task_exist(pfm_context_t *ctx) |
| { |
| struct task_struct *g, *t; |
| int ret = -ESRCH; |
| |
| read_lock(&tasklist_lock); |
| |
| do_each_thread (g, t) { |
| if (t->thread.pfm_context == ctx) { |
| ret = 0; |
| break; |
| } |
| } while_each_thread (g, t); |
| |
| read_unlock(&tasklist_lock); |
| |
| DPRINT(("pfm_check_task_exist: ret=%d ctx=%p\n", ret, ctx)); |
| |
| return ret; |
| } |
| |
| static int |
| pfm_context_load(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct task_struct *task; |
| struct thread_struct *thread; |
| struct pfm_context_t *old; |
| unsigned long flags; |
| #ifndef CONFIG_SMP |
| struct task_struct *owner_task = NULL; |
| #endif |
| pfarg_load_t *req = (pfarg_load_t *)arg; |
| unsigned long *pmcs_source, *pmds_source; |
| int the_cpu; |
| int ret = 0; |
| int state, is_system, set_dbregs = 0; |
| |
| state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| /* |
| * can only load from unloaded or terminated state |
| */ |
| if (state != PFM_CTX_UNLOADED) { |
| DPRINT(("cannot load to [%d], invalid ctx_state=%d\n", |
| req->load_pid, |
| ctx->ctx_state)); |
| return -EBUSY; |
| } |
| |
| DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg)); |
| |
| if (CTX_OVFL_NOBLOCK(ctx) == 0 && req->load_pid == current->pid) { |
| DPRINT(("cannot use blocking mode on self\n")); |
| return -EINVAL; |
| } |
| |
| ret = pfm_get_task(ctx, req->load_pid, &task); |
| if (ret) { |
| DPRINT(("load_pid [%d] get_task=%d\n", req->load_pid, ret)); |
| return ret; |
| } |
| |
| ret = -EINVAL; |
| |
| /* |
| * system wide is self monitoring only |
| */ |
| if (is_system && task != current) { |
| DPRINT(("system wide is self monitoring only load_pid=%d\n", |
| req->load_pid)); |
| goto error; |
| } |
| |
| thread = &task->thread; |
| |
| ret = 0; |
| /* |
| * cannot load a context which is using range restrictions, |
| * into a task that is being debugged. |
| */ |
| if (ctx->ctx_fl_using_dbreg) { |
| if (thread->flags & IA64_THREAD_DBG_VALID) { |
| ret = -EBUSY; |
| DPRINT(("load_pid [%d] task is debugged, cannot load range restrictions\n", req->load_pid)); |
| goto error; |
| } |
| LOCK_PFS(flags); |
| |
| if (is_system) { |
| if (pfm_sessions.pfs_ptrace_use_dbregs) { |
| DPRINT(("cannot load [%d] dbregs in use\n", task->pid)); |
| ret = -EBUSY; |
| } else { |
| pfm_sessions.pfs_sys_use_dbregs++; |
| DPRINT(("load [%d] increased sys_use_dbreg=%u\n", task->pid, pfm_sessions.pfs_sys_use_dbregs)); |
| set_dbregs = 1; |
| } |
| } |
| |
| UNLOCK_PFS(flags); |
| |
| if (ret) goto error; |
| } |
| |
| /* |
| * SMP system-wide monitoring implies self-monitoring. |
| * |
| * The programming model expects the task to |
| * be pinned on a CPU throughout the session. |
| * Here we take note of the current CPU at the |
| * time the context is loaded. No call from |
| * another CPU will be allowed. |
| * |
| * The pinning via shed_setaffinity() |
| * must be done by the calling task prior |
| * to this call. |
| * |
| * systemwide: keep track of CPU this session is supposed to run on |
| */ |
| the_cpu = ctx->ctx_cpu = smp_processor_id(); |
| |
| ret = -EBUSY; |
| /* |
| * now reserve the session |
| */ |
| ret = pfm_reserve_session(current, is_system, the_cpu); |
| if (ret) goto error; |
| |
| /* |
| * task is necessarily stopped at this point. |
| * |
| * If the previous context was zombie, then it got removed in |
| * pfm_save_regs(). Therefore we should not see it here. |
| * If we see a context, then this is an active context |
| * |
| * XXX: needs to be atomic |
| */ |
| DPRINT(("before cmpxchg() old_ctx=%p new_ctx=%p\n", |
| thread->pfm_context, ctx)); |
| |
| ret = -EBUSY; |
| old = ia64_cmpxchg(acq, &thread->pfm_context, NULL, ctx, sizeof(pfm_context_t *)); |
| if (old != NULL) { |
| DPRINT(("load_pid [%d] already has a context\n", req->load_pid)); |
| goto error_unres; |
| } |
| |
| pfm_reset_msgq(ctx); |
| |
| ctx->ctx_state = PFM_CTX_LOADED; |
| |
| /* |
| * link context to task |
| */ |
| ctx->ctx_task = task; |
| |
| if (is_system) { |
| /* |
| * we load as stopped |
| */ |
| PFM_CPUINFO_SET(PFM_CPUINFO_SYST_WIDE); |
| PFM_CPUINFO_CLEAR(PFM_CPUINFO_DCR_PP); |
| |
| if (ctx->ctx_fl_excl_idle) PFM_CPUINFO_SET(PFM_CPUINFO_EXCL_IDLE); |
| } else { |
| thread->flags |= IA64_THREAD_PM_VALID; |
| } |
| |
| /* |
| * propagate into thread-state |
| */ |
| pfm_copy_pmds(task, ctx); |
| pfm_copy_pmcs(task, ctx); |
| |
| pmcs_source = thread->pmcs; |
| pmds_source = thread->pmds; |
| |
| /* |
| * always the case for system-wide |
| */ |
| if (task == current) { |
| |
| if (is_system == 0) { |
| |
| /* allow user level control */ |
| ia64_psr(regs)->sp = 0; |
| DPRINT(("clearing psr.sp for [%d]\n", task->pid)); |
| |
| SET_LAST_CPU(ctx, smp_processor_id()); |
| INC_ACTIVATION(); |
| SET_ACTIVATION(ctx); |
| #ifndef CONFIG_SMP |
| /* |
| * push the other task out, if any |
| */ |
| owner_task = GET_PMU_OWNER(); |
| if (owner_task) pfm_lazy_save_regs(owner_task); |
| #endif |
| } |
| /* |
| * load all PMD from ctx to PMU (as opposed to thread state) |
| * restore all PMC from ctx to PMU |
| */ |
| pfm_restore_pmds(pmds_source, ctx->ctx_all_pmds[0]); |
| pfm_restore_pmcs(pmcs_source, ctx->ctx_all_pmcs[0]); |
| |
| ctx->ctx_reload_pmcs[0] = 0UL; |
| ctx->ctx_reload_pmds[0] = 0UL; |
| |
| /* |
| * guaranteed safe by earlier check against DBG_VALID |
| */ |
| if (ctx->ctx_fl_using_dbreg) { |
| pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); |
| pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); |
| } |
| /* |
| * set new ownership |
| */ |
| SET_PMU_OWNER(task, ctx); |
| |
| DPRINT(("context loaded on PMU for [%d]\n", task->pid)); |
| } else { |
| /* |
| * when not current, task MUST be stopped, so this is safe |
| */ |
| regs = ia64_task_regs(task); |
| |
| /* force a full reload */ |
| ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; |
| SET_LAST_CPU(ctx, -1); |
| |
| /* initial saved psr (stopped) */ |
| ctx->ctx_saved_psr_up = 0UL; |
| ia64_psr(regs)->up = ia64_psr(regs)->pp = 0; |
| } |
| |
| ret = 0; |
| |
| error_unres: |
| if (ret) pfm_unreserve_session(ctx, ctx->ctx_fl_system, the_cpu); |
| error: |
| /* |
| * we must undo the dbregs setting (for system-wide) |
| */ |
| if (ret && set_dbregs) { |
| LOCK_PFS(flags); |
| pfm_sessions.pfs_sys_use_dbregs--; |
| UNLOCK_PFS(flags); |
| } |
| /* |
| * release task, there is now a link with the context |
| */ |
| if (is_system == 0 && task != current) { |
| pfm_put_task(task); |
| |
| if (ret == 0) { |
| ret = pfm_check_task_exist(ctx); |
| if (ret) { |
| ctx->ctx_state = PFM_CTX_UNLOADED; |
| ctx->ctx_task = NULL; |
| } |
| } |
| } |
| return ret; |
| } |
| |
| /* |
| * in this function, we do not need to increase the use count |
| * for the task via get_task_struct(), because we hold the |
| * context lock. If the task were to disappear while having |
| * a context attached, it would go through pfm_exit_thread() |
| * which also grabs the context lock and would therefore be blocked |
| * until we are here. |
| */ |
| static void pfm_flush_pmds(struct task_struct *, pfm_context_t *ctx); |
| |
| static int |
| pfm_context_unload(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs) |
| { |
| struct task_struct *task = PFM_CTX_TASK(ctx); |
| struct pt_regs *tregs; |
| int prev_state, is_system; |
| int ret; |
| |
| DPRINT(("ctx_state=%d task [%d]\n", ctx->ctx_state, task ? task->pid : -1)); |
| |
| prev_state = ctx->ctx_state; |
| is_system = ctx->ctx_fl_system; |
| |
| /* |
| * unload only when necessary |
| */ |
| if (prev_state == PFM_CTX_UNLOADED) { |
| DPRINT(("ctx_state=%d, nothing to do\n", prev_state)); |
| return 0; |
| } |
| |
| /* |
| * clear psr and dcr bits |
| */ |
| ret = pfm_stop(ctx, NULL, 0, regs); |
| if (ret) return ret; |
| |
| ctx->ctx_state = PFM_CTX_UNLOADED; |
| |
| /* |
| * in system mode, we need to update the PMU directly |
| * and the user level state of the caller, which may not |
| * necessarily be the creator of the context. |
| */ |
| if (is_system) { |
| |
| /* |
| * Update cpuinfo |
| * |
| * local PMU is taken care of in pfm_stop() |
| */ |
| PFM_CPUINFO_CLEAR(PFM_CPUINFO_SYST_WIDE); |
| PFM_CPUINFO_CLEAR(PFM_CPUINFO_EXCL_IDLE); |
| |
| /* |
| * save PMDs in context |
| * release ownership |
| */ |
| pfm_flush_pmds(current, ctx); |
| |
| /* |
| * at this point we are done with the PMU |
| * so we can unreserve the resource. |
| */ |
| if (prev_state != PFM_CTX_ZOMBIE) |
| pfm_unreserve_session(ctx, 1 , ctx->ctx_cpu); |
| |
| /* |
| * disconnect context from task |
| */ |
| task->thread.pfm_context = NULL; |
| /* |
| * disconnect task from context |
| */ |
| ctx->ctx_task = NULL; |
| |
| /* |
| * There is nothing more to cleanup here. |
| */ |
| return 0; |
| } |
| |
| /* |
| * per-task mode |
| */ |
| tregs = task == current ? regs : ia64_task_regs(task); |
| |
| if (task == current) { |
| /* |
| * cancel user level control |
| */ |
| ia64_psr(regs)->sp = 1; |
| |
| DPRINT(("setting psr.sp for [%d]\n", task->pid)); |
| } |
| /* |
| * save PMDs to context |
| * release ownership |
| */ |
| pfm_flush_pmds(task, ctx); |
| |
| /* |
| * at this point we are done with the PMU |
| * so we can unreserve the resource. |
| * |
| * when state was ZOMBIE, we have already unreserved. |
| */ |
| if (prev_state != PFM_CTX_ZOMBIE) |
| pfm_unreserve_session(ctx, 0 , ctx->ctx_cpu); |
| |
| /* |
| * reset activation counter and psr |
| */ |
| ctx->ctx_last_activation = PFM_INVALID_ACTIVATION; |
| SET_LAST_CPU(ctx, -1); |
| |
| /* |
| * PMU state will not be restored |
| */ |
| task->thread.flags &= ~IA64_THREAD_PM_VALID; |
| |
| /* |
| * break links between context and task |
| */ |
| task->thread.pfm_context = NULL; |
| ctx->ctx_task = NULL; |
| |
| PFM_SET_WORK_PENDING(task, 0); |
| |
| ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE; |
| ctx->ctx_fl_can_restart = 0; |
| ctx->ctx_fl_going_zombie = 0; |
| |
| DPRINT(("disconnected [%d] from context\n", task->pid)); |
| |
| return 0; |
| } |
| |
| |
| /* |
| * called only from exit_thread(): task == current |
| * we come here only if current has a context attached (loaded or masked) |
| */ |
| void |
| pfm_exit_thread(struct task_struct *task) |
| { |
| pfm_context_t *ctx; |
| unsigned long flags; |
| struct pt_regs *regs = ia64_task_regs(task); |
| int ret, state; |
| int free_ok = 0; |
| |
| ctx = PFM_GET_CTX(task); |
| |
| PROTECT_CTX(ctx, flags); |
| |
| DPRINT(("state=%d task [%d]\n", ctx->ctx_state, task->pid)); |
| |
| state = ctx->ctx_state; |
| switch(state) { |
| case PFM_CTX_UNLOADED: |
| /* |
| * only comes to thios function if pfm_context is not NULL, i.e., cannot |
| * be in unloaded state |
| */ |
| printk(KERN_ERR "perfmon: pfm_exit_thread [%d] ctx unloaded\n", task->pid); |
| break; |
| case PFM_CTX_LOADED: |
| case PFM_CTX_MASKED: |
| ret = pfm_context_unload(ctx, NULL, 0, regs); |
| if (ret) { |
| printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task->pid, state, ret); |
| } |
| DPRINT(("ctx unloaded for current state was %d\n", state)); |
| |
| pfm_end_notify_user(ctx); |
| break; |
| case PFM_CTX_ZOMBIE: |
| ret = pfm_context_unload(ctx, NULL, 0, regs); |
| if (ret) { |
| printk(KERN_ERR "perfmon: pfm_exit_thread [%d] state=%d unload failed %d\n", task->pid, state, ret); |
| } |
| free_ok = 1; |
| break; |
| default: |
| printk(KERN_ERR "perfmon: pfm_exit_thread [%d] unexpected state=%d\n", task->pid, state); |
| break; |
| } |
| UNPROTECT_CTX(ctx, flags); |
| |
| { u64 psr = pfm_get_psr(); |
| BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); |
| BUG_ON(GET_PMU_OWNER()); |
| BUG_ON(ia64_psr(regs)->up); |
| BUG_ON(ia64_psr(regs)->pp); |
| } |
| |
| /* |
| * All memory free operations (especially for vmalloc'ed memory) |
| * MUST be done with interrupts ENABLED. |
| */ |
| if (free_ok) pfm_context_free(ctx); |
| } |
| |
| /* |
| * functions MUST be listed in the increasing order of their index (see permfon.h) |
| */ |
| #define PFM_CMD(name, flags, arg_count, arg_type, getsz) { name, #name, flags, arg_count, sizeof(arg_type), getsz } |
| #define PFM_CMD_S(name, flags) { name, #name, flags, 0, 0, NULL } |
| #define PFM_CMD_PCLRWS (PFM_CMD_FD|PFM_CMD_ARG_RW|PFM_CMD_STOP) |
| #define PFM_CMD_PCLRW (PFM_CMD_FD|PFM_CMD_ARG_RW) |
| #define PFM_CMD_NONE { NULL, "no-cmd", 0, 0, 0, NULL} |
| |
| static pfm_cmd_desc_t pfm_cmd_tab[]={ |
| /* 0 */PFM_CMD_NONE, |
| /* 1 */PFM_CMD(pfm_write_pmcs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), |
| /* 2 */PFM_CMD(pfm_write_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), |
| /* 3 */PFM_CMD(pfm_read_pmds, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), |
| /* 4 */PFM_CMD_S(pfm_stop, PFM_CMD_PCLRWS), |
| /* 5 */PFM_CMD_S(pfm_start, PFM_CMD_PCLRWS), |
| /* 6 */PFM_CMD_NONE, |
| /* 7 */PFM_CMD_NONE, |
| /* 8 */PFM_CMD(pfm_context_create, PFM_CMD_ARG_RW, 1, pfarg_context_t, pfm_ctx_getsize), |
| /* 9 */PFM_CMD_NONE, |
| /* 10 */PFM_CMD_S(pfm_restart, PFM_CMD_PCLRW), |
| /* 11 */PFM_CMD_NONE, |
| /* 12 */PFM_CMD(pfm_get_features, PFM_CMD_ARG_RW, 1, pfarg_features_t, NULL), |
| /* 13 */PFM_CMD(pfm_debug, 0, 1, unsigned int, NULL), |
| /* 14 */PFM_CMD_NONE, |
| /* 15 */PFM_CMD(pfm_get_pmc_reset, PFM_CMD_ARG_RW, PFM_CMD_ARG_MANY, pfarg_reg_t, NULL), |
| /* 16 */PFM_CMD(pfm_context_load, PFM_CMD_PCLRWS, 1, pfarg_load_t, NULL), |
| /* 17 */PFM_CMD_S(pfm_context_unload, PFM_CMD_PCLRWS), |
| /* 18 */PFM_CMD_NONE, |
| /* 19 */PFM_CMD_NONE, |
| /* 20 */PFM_CMD_NONE, |
| /* 21 */PFM_CMD_NONE, |
| /* 22 */PFM_CMD_NONE, |
| /* 23 */PFM_CMD_NONE, |
| /* 24 */PFM_CMD_NONE, |
| /* 25 */PFM_CMD_NONE, |
| /* 26 */PFM_CMD_NONE, |
| /* 27 */PFM_CMD_NONE, |
| /* 28 */PFM_CMD_NONE, |
| /* 29 */PFM_CMD_NONE, |
| /* 30 */PFM_CMD_NONE, |
| /* 31 */PFM_CMD_NONE, |
| /* 32 */PFM_CMD(pfm_write_ibrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL), |
| /* 33 */PFM_CMD(pfm_write_dbrs, PFM_CMD_PCLRWS, PFM_CMD_ARG_MANY, pfarg_dbreg_t, NULL) |
| }; |
| #define PFM_CMD_COUNT (sizeof(pfm_cmd_tab)/sizeof(pfm_cmd_desc_t)) |
| |
| static int |
| pfm_check_task_state(pfm_context_t *ctx, int cmd, unsigned long flags) |
| { |
| struct task_struct *task; |
| int state, old_state; |
| |
| recheck: |
| state = ctx->ctx_state; |
| task = ctx->ctx_task; |
| |
| if (task == NULL) { |
| DPRINT(("context %d no task, state=%d\n", ctx->ctx_fd, state)); |
| return 0; |
| } |
| |
| DPRINT(("context %d state=%d [%d] task_state=%ld must_stop=%d\n", |
| ctx->ctx_fd, |
| state, |
| task->pid, |
| task->state, PFM_CMD_STOPPED(cmd))); |
| |
| /* |
| * self-monitoring always ok. |
| * |
| * for system-wide the caller can either be the creator of the |
| * context (to one to which the context is attached to) OR |
| * a task running on the same CPU as the session. |
| */ |
| if (task == current || ctx->ctx_fl_system) return 0; |
| |
| /* |
| * we are monitoring another thread |
| */ |
| switch(state) { |
| case PFM_CTX_UNLOADED: |
| /* |
| * if context is UNLOADED we are safe to go |
| */ |
| return 0; |
| case PFM_CTX_ZOMBIE: |
| /* |
| * no command can operate on a zombie context |
| */ |
| DPRINT(("cmd %d state zombie cannot operate on context\n", cmd)); |
| return -EINVAL; |
| case PFM_CTX_MASKED: |
| /* |
| * PMU state has been saved to software even though |
| * the thread may still be running. |
| */ |
| if (cmd != PFM_UNLOAD_CONTEXT) return 0; |
| } |
| |
| /* |
| * context is LOADED or MASKED. Some commands may need to have |
| * the task stopped. |
| * |
| * We could lift this restriction for UP but it would mean that |
| * the user has no guarantee the task would not run between |
| * two successive calls to perfmonctl(). That's probably OK. |
| * If this user wants to ensure the task does not run, then |
| * the task must be stopped. |
| */ |
| if (PFM_CMD_STOPPED(cmd)) { |
| if ((task->state != TASK_STOPPED) && (task->state != TASK_TRACED)) { |
| DPRINT(("[%d] task not in stopped state\n", task->pid)); |
| return -EBUSY; |
| } |
| /* |
| * task is now stopped, wait for ctxsw out |
| * |
| * This is an interesting point in the code. |
| * We need to unprotect the context because |
| * the pfm_save_regs() routines needs to grab |
| * the same lock. There are danger in doing |
| * this because it leaves a window open for |
| * another task to get access to the context |
| * and possibly change its state. The one thing |
| * that is not possible is for the context to disappear |
| * because we are protected by the VFS layer, i.e., |
| * get_fd()/put_fd(). |
| */ |
| old_state = state; |
| |
| UNPROTECT_CTX(ctx, flags); |
| |
| wait_task_inactive(task); |
| |
| PROTECT_CTX(ctx, flags); |
| |
| /* |
| * we must recheck to verify if state has changed |
| */ |
| if (ctx->ctx_state != old_state) { |
| DPRINT(("old_state=%d new_state=%d\n", old_state, ctx->ctx_state)); |
| goto recheck; |
| } |
| } |
| return 0; |
| } |
| |
| /* |
| * system-call entry point (must return long) |
| */ |
| asmlinkage long |
| sys_perfmonctl (int fd, int cmd, void __user *arg, int count) |
| { |
| struct file *file = NULL; |
| pfm_context_t *ctx = NULL; |
| unsigned long flags = 0UL; |
| void *args_k = NULL; |
| long ret; /* will expand int return types */ |
| size_t base_sz, sz, xtra_sz = 0; |
| int narg, completed_args = 0, call_made = 0, cmd_flags; |
| int (*func)(pfm_context_t *ctx, void *arg, int count, struct pt_regs *regs); |
| int (*getsize)(void *arg, size_t *sz); |
| #define PFM_MAX_ARGSIZE 4096 |
| |
| /* |
| * reject any call if perfmon was disabled at initialization |
| */ |
| if (unlikely(pmu_conf == NULL)) return -ENOSYS; |
| |
| if (unlikely(cmd < 0 || cmd >= PFM_CMD_COUNT)) { |
| DPRINT(("invalid cmd=%d\n", cmd)); |
| return -EINVAL; |
| } |
| |
| func = pfm_cmd_tab[cmd].cmd_func; |
| narg = pfm_cmd_tab[cmd].cmd_narg; |
| base_sz = pfm_cmd_tab[cmd].cmd_argsize; |
| getsize = pfm_cmd_tab[cmd].cmd_getsize; |
| cmd_flags = pfm_cmd_tab[cmd].cmd_flags; |
| |
| if (unlikely(func == NULL)) { |
| DPRINT(("invalid cmd=%d\n", cmd)); |
| return -EINVAL; |
| } |
| |
| DPRINT(("cmd=%s idx=%d narg=0x%x argsz=%lu count=%d\n", |
| PFM_CMD_NAME(cmd), |
| cmd, |
| narg, |
| base_sz, |
| count)); |
| |
| /* |
| * check if number of arguments matches what the command expects |
| */ |
| if (unlikely((narg == PFM_CMD_ARG_MANY && count <= 0) || (narg > 0 && narg != count))) |
| return -EINVAL; |
| |
| restart_args: |
| sz = xtra_sz + base_sz*count; |
| /* |
| * limit abuse to min page size |
| */ |
| if (unlikely(sz > PFM_MAX_ARGSIZE)) { |
| printk(KERN_ERR "perfmon: [%d] argument too big %lu\n", current->pid, sz); |
| return -E2BIG; |
| } |
| |
| /* |
| * allocate default-sized argument buffer |
| */ |
| if (likely(count && args_k == NULL)) { |
| args_k = kmalloc(PFM_MAX_ARGSIZE, GFP_KERNEL); |
| if (args_k == NULL) return -ENOMEM; |
| } |
| |
| ret = -EFAULT; |
| |
| /* |
| * copy arguments |
| * |
| * assume sz = 0 for command without parameters |
| */ |
| if (sz && copy_from_user(args_k, arg, sz)) { |
| DPRINT(("cannot copy_from_user %lu bytes @%p\n", sz, arg)); |
| goto error_args; |
| } |
| |
| /* |
| * check if command supports extra parameters |
| */ |
| if (completed_args == 0 && getsize) { |
| /* |
| * get extra parameters size (based on main argument) |
| */ |
| ret = (*getsize)(args_k, &xtra_sz); |
| if (ret) goto error_args; |
| |
| completed_args = 1; |
| |
| DPRINT(("restart_args sz=%lu xtra_sz=%lu\n", sz, xtra_sz)); |
| |
| /* retry if necessary */ |
| if (likely(xtra_sz)) goto restart_args; |
| } |
| |
| if (unlikely((cmd_flags & PFM_CMD_FD) == 0)) goto skip_fd; |
| |
| ret = -EBADF; |
| |
| file = fget(fd); |
| if (unlikely(file == NULL)) { |
| DPRINT(("invalid fd %d\n", fd)); |
| goto error_args; |
| } |
| if (unlikely(PFM_IS_FILE(file) == 0)) { |
| DPRINT(("fd %d not related to perfmon\n", fd)); |
| goto error_args; |
| } |
| |
| ctx = (pfm_context_t *)file->private_data; |
| if (unlikely(ctx == NULL)) { |
| DPRINT(("no context for fd %d\n", fd)); |
| goto error_args; |
| } |
| prefetch(&ctx->ctx_state); |
| |
| PROTECT_CTX(ctx, flags); |
| |
| /* |
| * check task is stopped |
| */ |
| ret = pfm_check_task_state(ctx, cmd, flags); |
| if (unlikely(ret)) goto abort_locked; |
| |
| skip_fd: |
| ret = (*func)(ctx, args_k, count, ia64_task_regs(current)); |
| |
| call_made = 1; |
| |
| abort_locked: |
| if (likely(ctx)) { |
| DPRINT(("context unlocked\n")); |
| UNPROTECT_CTX(ctx, flags); |
| fput(file); |
| } |
| |
| /* copy argument back to user, if needed */ |
| if (call_made && PFM_CMD_RW_ARG(cmd) && copy_to_user(arg, args_k, base_sz*count)) ret = -EFAULT; |
| |
| error_args: |
| if (args_k) kfree(args_k); |
| |
| DPRINT(("cmd=%s ret=%ld\n", PFM_CMD_NAME(cmd), ret)); |
| |
| return ret; |
| } |
| |
| static void |
| pfm_resume_after_ovfl(pfm_context_t *ctx, unsigned long ovfl_regs, struct pt_regs *regs) |
| { |
| pfm_buffer_fmt_t *fmt = ctx->ctx_buf_fmt; |
| pfm_ovfl_ctrl_t rst_ctrl; |
| int state; |
| int ret = 0; |
| |
| state = ctx->ctx_state; |
| /* |
| * Unlock sampling buffer and reset index atomically |
| * XXX: not really needed when blocking |
| */ |
| if (CTX_HAS_SMPL(ctx)) { |
| |
| rst_ctrl.bits.mask_monitoring = 0; |
| rst_ctrl.bits.reset_ovfl_pmds = 0; |
| |
| if (state == PFM_CTX_LOADED) |
| ret = pfm_buf_fmt_restart_active(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs); |
| else |
| ret = pfm_buf_fmt_restart(fmt, current, &rst_ctrl, ctx->ctx_smpl_hdr, regs); |
| } else { |
| rst_ctrl.bits.mask_monitoring = 0; |
| rst_ctrl.bits.reset_ovfl_pmds = 1; |
| } |
| |
| if (ret == 0) { |
| if (rst_ctrl.bits.reset_ovfl_pmds) { |
| pfm_reset_regs(ctx, &ovfl_regs, PFM_PMD_LONG_RESET); |
| } |
| if (rst_ctrl.bits.mask_monitoring == 0) { |
| DPRINT(("resuming monitoring\n")); |
| if (ctx->ctx_state == PFM_CTX_MASKED) pfm_restore_monitoring(current); |
| } else { |
| DPRINT(("stopping monitoring\n")); |
| //pfm_stop_monitoring(current, regs); |
| } |
| ctx->ctx_state = PFM_CTX_LOADED; |
| } |
| } |
| |
| /* |
| * context MUST BE LOCKED when calling |
| * can only be called for current |
| */ |
| static void |
| pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs) |
| { |
| int ret; |
| |
| DPRINT(("entering for [%d]\n", current->pid)); |
| |
| ret = pfm_context_unload(ctx, NULL, 0, regs); |
| if (ret) { |
| printk(KERN_ERR "pfm_context_force_terminate: [%d] unloaded failed with %d\n", current->pid, ret); |
| } |
| |
| /* |
| * and wakeup controlling task, indicating we are now disconnected |
| */ |
| wake_up_interruptible(&ctx->ctx_zombieq); |
| |
| /* |
| * given that context is still locked, the controlling |
| * task will only get access when we return from |
| * pfm_handle_work(). |
| */ |
| } |
| |
| static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds); |
| /* |
| * pfm_handle_work() can be called with interrupts enabled |
| * (TIF_NEED_RESCHED) or disabled. The down_interruptible |
| * call may sleep, therefore we must re-enable interrupts |
| * to avoid deadlocks. It is safe to do so because this function |
| * is called ONLY when returning to user level (PUStk=1), in which case |
| * there is no risk of kernel stack overflow due to deep |
| * interrupt nesting. |
| */ |
| void |
| pfm_handle_work(void) |
| { |
| pfm_context_t *ctx; |
| struct pt_regs *regs; |
| unsigned long flags, dummy_flags; |
| unsigned long ovfl_regs; |
| unsigned int reason; |
| int ret; |
| |
| ctx = PFM_GET_CTX(current); |
| if (ctx == NULL) { |
| printk(KERN_ERR "perfmon: [%d] has no PFM context\n", current->pid); |
| return; |
| } |
| |
| PROTECT_CTX(ctx, flags); |
| |
| PFM_SET_WORK_PENDING(current, 0); |
| |
| pfm_clear_task_notify(); |
| |
| regs = ia64_task_regs(current); |
| |
| /* |
| * extract reason for being here and clear |
| */ |
| reason = ctx->ctx_fl_trap_reason; |
| ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_NONE; |
| ovfl_regs = ctx->ctx_ovfl_regs[0]; |
| |
| DPRINT(("reason=%d state=%d\n", reason, ctx->ctx_state)); |
| |
| /* |
| * must be done before we check for simple-reset mode |
| */ |
| if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE) goto do_zombie; |
| |
| |
| //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking; |
| if (reason == PFM_TRAP_REASON_RESET) goto skip_blocking; |
| |
| /* |
| * restore interrupt mask to what it was on entry. |
| * Could be enabled/diasbled. |
| */ |
| UNPROTECT_CTX(ctx, flags); |
| |
| /* |
| * force interrupt enable because of down_interruptible() |
| */ |
| local_irq_enable(); |
| |
| DPRINT(("before block sleeping\n")); |
| |
| /* |
| * may go through without blocking on SMP systems |
| * if restart has been received already by the time we call down() |
| */ |
| ret = down_interruptible(&ctx->ctx_restart_sem); |
| |
| DPRINT(("after block sleeping ret=%d\n", ret)); |
| |
| /* |
| * lock context and mask interrupts again |
| * We save flags into a dummy because we may have |
| * altered interrupts mask compared to entry in this |
| * function. |
| */ |
| PROTECT_CTX(ctx, dummy_flags); |
| |
| /* |
| * we need to read the ovfl_regs only after wake-up |
| * because we may have had pfm_write_pmds() in between |
| * and that can changed PMD values and therefore |
| * ovfl_regs is reset for these new PMD values. |
| */ |
| ovfl_regs = ctx->ctx_ovfl_regs[0]; |
| |
| if (ctx->ctx_fl_going_zombie) { |
| do_zombie: |
| DPRINT(("context is zombie, bailing out\n")); |
| pfm_context_force_terminate(ctx, regs); |
| goto nothing_to_do; |
| } |
| /* |
| * in case of interruption of down() we don't restart anything |
| */ |
| if (ret < 0) goto nothing_to_do; |
| |
| skip_blocking: |
| pfm_resume_after_ovfl(ctx, ovfl_regs, regs); |
| ctx->ctx_ovfl_regs[0] = 0UL; |
| |
| nothing_to_do: |
| /* |
| * restore flags as they were upon entry |
| */ |
| UNPROTECT_CTX(ctx, flags); |
| } |
| |
| static int |
| pfm_notify_user(pfm_context_t *ctx, pfm_msg_t *msg) |
| { |
| if (ctx->ctx_state == PFM_CTX_ZOMBIE) { |
| DPRINT(("ignoring overflow notification, owner is zombie\n")); |
| return 0; |
| } |
| |
| DPRINT(("waking up somebody\n")); |
| |
| if (msg) wake_up_interruptible(&ctx->ctx_msgq_wait); |
| |
| /* |
| * safe, we are not in intr handler, nor in ctxsw when |
| * we come here |
| */ |
| kill_fasync (&ctx->ctx_async_queue, SIGIO, POLL_IN); |
| |
| return 0; |
| } |
| |
| static int |
| pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds) |
| { |
| pfm_msg_t *msg = NULL; |
| |
| if (ctx->ctx_fl_no_msg == 0) { |
| msg = pfm_get_new_msg(ctx); |
| if (msg == NULL) { |
| printk(KERN_ERR "perfmon: pfm_ovfl_notify_user no more notification msgs\n"); |
| return -1; |
| } |
| |
| msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL; |
| msg->pfm_ovfl_msg.msg_ctx_fd = ctx->ctx_fd; |
| msg->pfm_ovfl_msg.msg_active_set = 0; |
| msg->pfm_ovfl_msg.msg_ovfl_pmds[0] = ovfl_pmds; |
| msg->pfm_ovfl_msg.msg_ovfl_pmds[1] = 0UL; |
| msg->pfm_ovfl_msg.msg_ovfl_pmds[2] = 0UL; |
| msg->pfm_ovfl_msg.msg_ovfl_pmds[3] = 0UL; |
| msg->pfm_ovfl_msg.msg_tstamp = 0UL; |
| } |
| |
| DPRINT(("ovfl msg: msg=%p no_msg=%d fd=%d ovfl_pmds=0x%lx\n", |
| msg, |
| ctx->ctx_fl_no_msg, |
| ctx->ctx_fd, |
| ovfl_pmds)); |
| |
| return pfm_notify_user(ctx, msg); |
| } |
| |
| static int |
| pfm_end_notify_user(pfm_context_t *ctx) |
| { |
| pfm_msg_t *msg; |
| |
| msg = pfm_get_new_msg(ctx); |
| if (msg == NULL) { |
| printk(KERN_ERR "perfmon: pfm_end_notify_user no more notification msgs\n"); |
| return -1; |
| } |
| /* no leak */ |
| memset(msg, 0, sizeof(*msg)); |
| |
| msg->pfm_end_msg.msg_type = PFM_MSG_END; |
| msg->pfm_end_msg.msg_ctx_fd = ctx->ctx_fd; |
| msg->pfm_ovfl_msg.msg_tstamp = 0UL; |
| |
| DPRINT(("end msg: msg=%p no_msg=%d ctx_fd=%d\n", |
| msg, |
| ctx->ctx_fl_no_msg, |
| ctx->ctx_fd)); |
| |
| return pfm_notify_user(ctx, msg); |
| } |
| |
| /* |
| * main overflow processing routine. |
| * it can be called from the interrupt path or explicitely during the context switch code |
| */ |
| static void |
| pfm_overflow_handler(struct task_struct *task, pfm_context_t *ctx, u64 pmc0, struct pt_regs *regs) |
| { |
| pfm_ovfl_arg_t *ovfl_arg; |
| unsigned long mask; |
| unsigned long old_val, ovfl_val, new_val; |
| unsigned long ovfl_notify = 0UL, ovfl_pmds = 0UL, smpl_pmds = 0UL, reset_pmds; |
| unsigned long tstamp; |
| pfm_ovfl_ctrl_t ovfl_ctrl; |
| unsigned int i, has_smpl; |
| int must_notify = 0; |
| |
| if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) goto stop_monitoring; |
| |
| /* |
| * sanity test. Should never happen |
| */ |
| if (unlikely((pmc0 & 0x1) == 0)) goto sanity_check; |
| |
| tstamp = ia64_get_itc(); |
| mask = pmc0 >> PMU_FIRST_COUNTER; |
| ovfl_val = pmu_conf->ovfl_val; |
| has_smpl = CTX_HAS_SMPL(ctx); |
| |
| DPRINT_ovfl(("pmc0=0x%lx pid=%d iip=0x%lx, %s " |
| "used_pmds=0x%lx\n", |
| pmc0, |
| task ? task->pid: -1, |
| (regs ? regs->cr_iip : 0), |
| CTX_OVFL_NOBLOCK(ctx) ? "nonblocking" : "blocking", |
| ctx->ctx_used_pmds[0])); |
| |
| |
| /* |
| * first we update the virtual counters |
| * assume there was a prior ia64_srlz_d() issued |
| */ |
| for (i = PMU_FIRST_COUNTER; mask ; i++, mask >>= 1) { |
| |
| /* skip pmd which did not overflow */ |
| if ((mask & 0x1) == 0) continue; |
| |
| /* |
| * Note that the pmd is not necessarily 0 at this point as qualified events |
| * may have happened before the PMU was frozen. The residual count is not |
| * taken into consideration here but will be with any read of the pmd via |
| * pfm_read_pmds(). |
| */ |
| old_val = new_val = ctx->ctx_pmds[i].val; |
| new_val += 1 + ovfl_val; |
| ctx->ctx_pmds[i].val = new_val; |
| |
| /* |
| * check for overflow condition |
| */ |
| if (likely(old_val > new_val)) { |
| ovfl_pmds |= 1UL << i; |
| if (PMC_OVFL_NOTIFY(ctx, i)) ovfl_notify |= 1UL << i; |
| } |
| |
| DPRINT_ovfl(("ctx_pmd[%d].val=0x%lx old_val=0x%lx pmd=0x%lx ovfl_pmds=0x%lx ovfl_notify=0x%lx\n", |
| i, |
| new_val, |
| old_val, |
| ia64_get_pmd(i) & ovfl_val, |
| ovfl_pmds, |
| ovfl_notify)); |
| } |
| |
| /* |
| * there was no 64-bit overflow, nothing else to do |
| */ |
| if (ovfl_pmds == 0UL) return; |
| |
| /* |
| * reset all control bits |
| */ |
| ovfl_ctrl.val = 0; |
| reset_pmds = 0UL; |
| |
| /* |
| * if a sampling format module exists, then we "cache" the overflow by |
| * calling the module's handler() routine. |
| */ |
| if (has_smpl) { |
| unsigned long start_cycles, end_cycles; |
| unsigned long pmd_mask; |
| int j, k, ret = 0; |
| int this_cpu = smp_processor_id(); |
| |
| pmd_mask = ovfl_pmds >> PMU_FIRST_COUNTER; |
| ovfl_arg = &ctx->ctx_ovfl_arg; |
| |
| prefetch(ctx->ctx_smpl_hdr); |
| |
| for(i=PMU_FIRST_COUNTER; pmd_mask && ret == 0; i++, pmd_mask >>=1) { |
| |
| mask = 1UL << i; |
| |
| if ((pmd_mask & 0x1) == 0) continue; |
| |
| ovfl_arg->ovfl_pmd = (unsigned char )i; |
| ovfl_arg->ovfl_notify = ovfl_notify & mask ? 1 : 0; |
| ovfl_arg->active_set = 0; |
| ovfl_arg->ovfl_ctrl.val = 0; /* module must fill in all fields */ |
| ovfl_arg->smpl_pmds[0] = smpl_pmds = ctx->ctx_pmds[i].smpl_pmds[0]; |
| |
| ovfl_arg->pmd_value = ctx->ctx_pmds[i].val; |
| ovfl_arg->pmd_last_reset = ctx->ctx_pmds[i].lval; |
| ovfl_arg->pmd_eventid = ctx->ctx_pmds[i].eventid; |
| |
| /* |
| * copy values of pmds of interest. Sampling format may copy them |
| * into sampling buffer. |
| */ |
| if (smpl_pmds) { |
| for(j=0, k=0; smpl_pmds; j++, smpl_pmds >>=1) { |
| if ((smpl_pmds & 0x1) == 0) continue; |
| ovfl_arg->smpl_pmds_values[k++] = PMD_IS_COUNTING(j) ? pfm_read_soft_counter(ctx, j) : ia64_get_pmd(j); |
| DPRINT_ovfl(("smpl_pmd[%d]=pmd%u=0x%lx\n", k-1, j, ovfl_arg->smpl_pmds_values[k-1])); |
| } |
| } |
| |
| pfm_stats[this_cpu].pfm_smpl_handler_calls++; |
| |
| start_cycles = ia64_get_itc(); |
| |
| /* |
| * call custom buffer format record (handler) routine |
| */ |
| ret = (*ctx->ctx_buf_fmt->fmt_handler)(task, ctx->ctx_smpl_hdr, ovfl_arg, regs, tstamp); |
| |
| end_cycles = ia64_get_itc(); |
| |
| /* |
| * For those controls, we take the union because they have |
| * an all or nothing behavior. |
| */ |
| ovfl_ctrl.bits.notify_user |= ovfl_arg->ovfl_ctrl.bits.notify_user; |
| ovfl_ctrl.bits.block_task |= ovfl_arg->ovfl_ctrl.bits.block_task; |
| ovfl_ctrl.bits.mask_monitoring |= ovfl_arg->ovfl_ctrl.bits.mask_monitoring; |
| /* |
| * build the bitmask of pmds to reset now |
| */ |
| if (ovfl_arg->ovfl_ctrl.bits.reset_ovfl_pmds) reset_pmds |= mask; |
| |
| pfm_stats[this_cpu].pfm_smpl_handler_cycles += end_cycles - start_cycles; |
| } |
| /* |
| * when the module cannot handle the rest of the overflows, we abort right here |
| */ |
| if (ret && pmd_mask) { |
| DPRINT(("handler aborts leftover ovfl_pmds=0x%lx\n", |
| pmd_mask<<PMU_FIRST_COUNTER)); |
| } |
| /* |
| * remove the pmds we reset now from the set of pmds to reset in pfm_restart() |
| */ |
| ovfl_pmds &= ~reset_pmds; |
| } else { |
| /* |
| * when no sampling module is used, then the default |
| * is to notify on overflow if requested by user |
| */ |
| ovfl_ctrl.bits.notify_user = ovfl_notify ? 1 : 0; |
| ovfl_ctrl.bits.block_task = ovfl_notify ? 1 : 0; |
| ovfl_ctrl.bits.mask_monitoring = ovfl_notify ? 1 : 0; /* XXX: change for saturation */ |
| ovfl_ctrl.bits.reset_ovfl_pmds = ovfl_notify ? 0 : 1; |
| /* |
| * if needed, we reset all overflowed pmds |
| */ |
| if (ovfl_notify == 0) reset_pmds = ovfl_pmds; |
| } |
| |
| DPRINT_ovfl(("ovfl_pmds=0x%lx reset_pmds=0x%lx\n", ovfl_pmds, reset_pmds)); |
| |
| /* |
| * reset the requested PMD registers using the short reset values |
| */ |
| if (reset_pmds) { |
| unsigned long bm = reset_pmds; |
| pfm_reset_regs(ctx, &bm, PFM_PMD_SHORT_RESET); |
| } |
| |
| if (ovfl_notify && ovfl_ctrl.bits.notify_user) { |
| /* |
| * keep track of what to reset when unblocking |
| */ |
| ctx->ctx_ovfl_regs[0] = ovfl_pmds; |
| |
| /* |
| * check for blocking context |
| */ |
| if (CTX_OVFL_NOBLOCK(ctx) == 0 && ovfl_ctrl.bits.block_task) { |
| |
| ctx->ctx_fl_trap_reason = PFM_TRAP_REASON_BLOCK; |
| |
| /* |
| * set the perfmon specific checking pending work for the task |
| */ |
| PFM_SET_WORK_PENDING(task, 1); |
| |
| /* |
| * when coming from ctxsw, current still points to the |
| * previous task, therefore we must work with task and not current. |
| */ |
| pfm_set_task_notify(task); |
| } |
| /* |
| * defer until state is changed (shorten spin window). the context is locked |
| * anyway, so the signal receiver would come spin for nothing. |
| */ |
| must_notify = 1; |
| } |
| |
| DPRINT_ovfl(("owner [%d] pending=%ld reason=%u ovfl_pmds=0x%lx ovfl_notify=0x%lx masked=%d\n", |
| GET_PMU_OWNER() ? GET_PMU_OWNER()->pid : -1, |
| PFM_GET_WORK_PENDING(task), |
| ctx->ctx_fl_trap_reason, |
| ovfl_pmds, |
| ovfl_notify, |
| ovfl_ctrl.bits.mask_monitoring ? 1 : 0)); |
| /* |
| * in case monitoring must be stopped, we toggle the psr bits |
| */ |
| if (ovfl_ctrl.bits.mask_monitoring) { |
| pfm_mask_monitoring(task); |
| ctx->ctx_state = PFM_CTX_MASKED; |
| ctx->ctx_fl_can_restart = 1; |
| } |
| |
| /* |
| * send notification now |
| */ |
| if (must_notify) pfm_ovfl_notify_user(ctx, ovfl_notify); |
| |
| return; |
| |
| sanity_check: |
| printk(KERN_ERR "perfmon: CPU%d overflow handler [%d] pmc0=0x%lx\n", |
| smp_processor_id(), |
| task ? task->pid : -1, |
| pmc0); |
| return; |
| |
| stop_monitoring: |
| /* |
| * in SMP, zombie context is never restored but reclaimed in pfm_load_regs(). |
| * Moreover, zombies are also reclaimed in pfm_save_regs(). Therefore we can |
| * come here as zombie only if the task is the current task. In which case, we |
| * can access the PMU hardware directly. |
| * |
| * Note that zombies do have PM_VALID set. So here we do the minimal. |
| * |
| * In case the context was zombified it could not be reclaimed at the time |
| * the monitoring program exited. At this point, the PMU reservation has been |
| * returned, the sampiing buffer has been freed. We must convert this call |
| * into a spurious interrupt. However, we must also avoid infinite overflows |
| * by stopping monitoring for this task. We can only come here for a per-task |
| * context. All we need to do is to stop monitoring using the psr bits which |
| * are always task private. By re-enabling secure montioring, we ensure that |
| * the monitored task will not be able to re-activate monitoring. |
| * The task will eventually be context switched out, at which point the context |
| * will be reclaimed (that includes releasing ownership of the PMU). |
| * |
| * So there might be a window of time where the number of per-task session is zero |
| * yet one PMU might have a owner and get at most one overflow interrupt for a zombie |
| * context. This is safe because if a per-task session comes in, it will push this one |
| * out and by the virtue on pfm_save_regs(), this one will disappear. If a system wide |
| * session is force on that CPU, given that we use task pinning, pfm_save_regs() will |
| * also push our zombie context out. |
| * |
| * Overall pretty hairy stuff.... |
| */ |
| DPRINT(("ctx is zombie for [%d], converted to spurious\n", task ? task->pid: -1)); |
| pfm_clear_psr_up(); |
| ia64_psr(regs)->up = 0; |
| ia64_psr(regs)->sp = 1; |
| return; |
| } |
| |
| static int |
| pfm_do_interrupt_handler(int irq, void *arg, struct pt_regs *regs) |
| { |
| struct task_struct *task; |
| pfm_context_t *ctx; |
| unsigned long flags; |
| u64 pmc0; |
| int this_cpu = smp_processor_id(); |
| int retval = 0; |
| |
| pfm_stats[this_cpu].pfm_ovfl_intr_count++; |
| |
| /* |
| * srlz.d done before arriving here |
| */ |
| pmc0 = ia64_get_pmc(0); |
| |
| task = GET_PMU_OWNER(); |
| ctx = GET_PMU_CTX(); |
| |
| /* |
| * if we have some pending bits set |
| * assumes : if any PMC0.bit[63-1] is set, then PMC0.fr = 1 |
| */ |
| if (PMC0_HAS_OVFL(pmc0) && task) { |
| /* |
| * we assume that pmc0.fr is always set here |
| */ |
| |
| /* sanity check */ |
| if (!ctx) goto report_spurious1; |
| |
| if (ctx->ctx_fl_system == 0 && (task->thread.flags & IA64_THREAD_PM_VALID) == 0) |
| goto report_spurious2; |
| |
| PROTECT_CTX_NOPRINT(ctx, flags); |
| |
| pfm_overflow_handler(task, ctx, pmc0, regs); |
| |
| UNPROTECT_CTX_NOPRINT(ctx, flags); |
| |
| } else { |
| pfm_stats[this_cpu].pfm_spurious_ovfl_intr_count++; |
| retval = -1; |
| } |
| /* |
| * keep it unfrozen at all times |
| */ |
| pfm_unfreeze_pmu(); |
| |
| return retval; |
| |
| report_spurious1: |
| printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d has no PFM context\n", |
| this_cpu, task->pid); |
| pfm_unfreeze_pmu(); |
| return -1; |
| report_spurious2: |
| printk(KERN_INFO "perfmon: spurious overflow interrupt on CPU%d: process %d, invalid flag\n", |
| this_cpu, |
| task->pid); |
| pfm_unfreeze_pmu(); |
| return -1; |
| } |
| |
| static irqreturn_t |
| pfm_interrupt_handler(int irq, void *arg, struct pt_regs *regs) |
| { |
| unsigned long start_cycles, total_cycles; |
| unsigned long min, max; |
| int this_cpu; |
| int ret; |
| |
| this_cpu = get_cpu(); |
| if (likely(!pfm_alt_intr_handler)) { |
| min = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min; |
| max = pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max; |
| |
| start_cycles = ia64_get_itc(); |
| |
| ret = pfm_do_interrupt_handler(irq, arg, regs); |
| |
| total_cycles = ia64_get_itc(); |
| |
| /* |
| * don't measure spurious interrupts |
| */ |
| if (likely(ret == 0)) { |
| total_cycles -= start_cycles; |
| |
| if (total_cycles < min) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_min = total_cycles; |
| if (total_cycles > max) pfm_stats[this_cpu].pfm_ovfl_intr_cycles_max = total_cycles; |
| |
| pfm_stats[this_cpu].pfm_ovfl_intr_cycles += total_cycles; |
| } |
| } |
| else { |
| (*pfm_alt_intr_handler->handler)(irq, arg, regs); |
| } |
| |
| put_cpu_no_resched(); |
| return IRQ_HANDLED; |
| } |
| |
| /* |
| * /proc/perfmon interface, for debug only |
| */ |
| |
| #define PFM_PROC_SHOW_HEADER ((void *)NR_CPUS+1) |
| |
| static void * |
| pfm_proc_start(struct seq_file *m, loff_t *pos) |
| { |
| if (*pos == 0) { |
| return PFM_PROC_SHOW_HEADER; |
| } |
| |
| while (*pos <= NR_CPUS) { |
| if (cpu_online(*pos - 1)) { |
| return (void *)*pos; |
| } |
| ++*pos; |
| } |
| return NULL; |
| } |
| |
| static void * |
| pfm_proc_next(struct seq_file *m, void *v, loff_t *pos) |
| { |
| ++*pos; |
| return pfm_proc_start(m, pos); |
| } |
| |
| static void |
| pfm_proc_stop(struct seq_file *m, void *v) |
| { |
| } |
| |
| static void |
| pfm_proc_show_header(struct seq_file *m) |
| { |
| struct list_head * pos; |
| pfm_buffer_fmt_t * entry; |
| unsigned long flags; |
| |
| seq_printf(m, |
| "perfmon version : %u.%u\n" |
| "model : %s\n" |
| "fastctxsw : %s\n" |
| "expert mode : %s\n" |
| "ovfl_mask : 0x%lx\n" |
| "PMU flags : 0x%x\n", |
| PFM_VERSION_MAJ, PFM_VERSION_MIN, |
| pmu_conf->pmu_name, |
| pfm_sysctl.fastctxsw > 0 ? "Yes": "No", |
| pfm_sysctl.expert_mode > 0 ? "Yes": "No", |
| pmu_conf->ovfl_val, |
| pmu_conf->flags); |
| |
| LOCK_PFS(flags); |
| |
| seq_printf(m, |
| "proc_sessions : %u\n" |
| "sys_sessions : %u\n" |
| "sys_use_dbregs : %u\n" |
| "ptrace_use_dbregs : %u\n", |
| pfm_sessions.pfs_task_sessions, |
| pfm_sessions.pfs_sys_sessions, |
| pfm_sessions.pfs_sys_use_dbregs, |
| pfm_sessions.pfs_ptrace_use_dbregs); |
| |
| UNLOCK_PFS(flags); |
| |
| spin_lock(&pfm_buffer_fmt_lock); |
| |
| list_for_each(pos, &pfm_buffer_fmt_list) { |
| entry = list_entry(pos, pfm_buffer_fmt_t, fmt_list); |
| seq_printf(m, "format : %02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x %s\n", |
| entry->fmt_uuid[0], |
| entry->fmt_uuid[1], |
| entry->fmt_uuid[2], |
| entry->fmt_uuid[3], |
| entry->fmt_uuid[4], |
| entry->fmt_uuid[5], |
| entry->fmt_uuid[6], |
| entry->fmt_uuid[7], |
| entry->fmt_uuid[8], |
| entry->fmt_uuid[9], |
| entry->fmt_uuid[10], |
| entry->fmt_uuid[11], |
| entry->fmt_uuid[12], |
| entry->fmt_uuid[13], |
| entry->fmt_uuid[14], |
| entry->fmt_uuid[15], |
| entry->fmt_name); |
| } |
| spin_unlock(&pfm_buffer_fmt_lock); |
| |
| } |
| |
| static int |
| pfm_proc_show(struct seq_file *m, void *v) |
| { |
| unsigned long psr; |
| unsigned int i; |
| int cpu; |
| |
| if (v == PFM_PROC_SHOW_HEADER) { |
| pfm_proc_show_header(m); |
| return 0; |
| } |
| |
| /* show info for CPU (v - 1) */ |
| |
| cpu = (long)v - 1; |
| seq_printf(m, |
| "CPU%-2d overflow intrs : %lu\n" |
| "CPU%-2d overflow cycles : %lu\n" |
| "CPU%-2d overflow min : %lu\n" |
| "CPU%-2d overflow max : %lu\n" |
| "CPU%-2d smpl handler calls : %lu\n" |
| "CPU%-2d smpl handler cycles : %lu\n" |
| "CPU%-2d spurious intrs : %lu\n" |
| "CPU%-2d replay intrs : %lu\n" |
| "CPU%-2d syst_wide : %d\n" |
| "CPU%-2d dcr_pp : %d\n" |
| "CPU%-2d exclude idle : %d\n" |
| "CPU%-2d owner : %d\n" |
| "CPU%-2d context : %p\n" |
| "CPU%-2d activations : %lu\n", |
| cpu, pfm_stats[cpu].pfm_ovfl_intr_count, |
| cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles, |
| cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_min, |
| cpu, pfm_stats[cpu].pfm_ovfl_intr_cycles_max, |
| cpu, pfm_stats[cpu].pfm_smpl_handler_calls, |
| cpu, pfm_stats[cpu].pfm_smpl_handler_cycles, |
| cpu, pfm_stats[cpu].pfm_spurious_ovfl_intr_count, |
| cpu, pfm_stats[cpu].pfm_replay_ovfl_intr_count, |
| cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_SYST_WIDE ? 1 : 0, |
| cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_DCR_PP ? 1 : 0, |
| cpu, pfm_get_cpu_data(pfm_syst_info, cpu) & PFM_CPUINFO_EXCL_IDLE ? 1 : 0, |
| cpu, pfm_get_cpu_data(pmu_owner, cpu) ? pfm_get_cpu_data(pmu_owner, cpu)->pid: -1, |
| cpu, pfm_get_cpu_data(pmu_ctx, cpu), |
| cpu, pfm_get_cpu_data(pmu_activation_number, cpu)); |
| |
| if (num_online_cpus() == 1 && pfm_sysctl.debug > 0) { |
| |
| psr = pfm_get_psr(); |
| |
| ia64_srlz_d(); |
| |
| seq_printf(m, |
| "CPU%-2d psr : 0x%lx\n" |
| "CPU%-2d pmc0 : 0x%lx\n", |
| cpu, psr, |
| cpu, ia64_get_pmc(0)); |
| |
| for (i=0; PMC_IS_LAST(i) == 0; i++) { |
| if (PMC_IS_COUNTING(i) == 0) continue; |
| seq_printf(m, |
| "CPU%-2d pmc%u : 0x%lx\n" |
| "CPU%-2d pmd%u : 0x%lx\n", |
| cpu, i, ia64_get_pmc(i), |
| cpu, i, ia64_get_pmd(i)); |
| } |
| } |
| return 0; |
| } |
| |
| struct seq_operations pfm_seq_ops = { |
| .start = pfm_proc_start, |
| .next = pfm_proc_next, |
| .stop = pfm_proc_stop, |
| .show = pfm_proc_show |
| }; |
| |
| static int |
| pfm_proc_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &pfm_seq_ops); |
| } |
| |
| |
| /* |
| * we come here as soon as local_cpu_data->pfm_syst_wide is set. this happens |
| * during pfm_enable() hence before pfm_start(). We cannot assume monitoring |
| * is active or inactive based on mode. We must rely on the value in |
| * local_cpu_data->pfm_syst_info |
| */ |
| void |
| pfm_syst_wide_update_task(struct task_struct *task, unsigned long info, int is_ctxswin) |
| { |
| struct pt_regs *regs; |
| unsigned long dcr; |
| unsigned long dcr_pp; |
| |
| dcr_pp = info & PFM_CPUINFO_DCR_PP ? 1 : 0; |
| |
| /* |
| * pid 0 is guaranteed to be the idle task. There is one such task with pid 0 |
| * on every CPU, so we can rely on the pid to identify the idle task. |
| */ |
| if ((info & PFM_CPUINFO_EXCL_IDLE) == 0 || task->pid) { |
| regs = ia64_task_regs(task); |
| ia64_psr(regs)->pp = is_ctxswin ? dcr_pp : 0; |
| return; |
| } |
| /* |
| * if monitoring has started |
| */ |
| if (dcr_pp) { |
| dcr = ia64_getreg(_IA64_REG_CR_DCR); |
| /* |
| * context switching in? |
| */ |
| if (is_ctxswin) { |
| /* mask monitoring for the idle task */ |
| ia64_setreg(_IA64_REG_CR_DCR, dcr & ~IA64_DCR_PP); |
| pfm_clear_psr_pp(); |
| ia64_srlz_i(); |
| return; |
| } |
| /* |
| * context switching out |
| * restore monitoring for next task |
| * |
| * Due to inlining this odd if-then-else construction generates |
| * better code. |
| */ |
| ia64_setreg(_IA64_REG_CR_DCR, dcr |IA64_DCR_PP); |
| pfm_set_psr_pp(); |
| ia64_srlz_i(); |
| } |
| } |
| |
| #ifdef CONFIG_SMP |
| |
| static void |
| pfm_force_cleanup(pfm_context_t *ctx, struct pt_regs *regs) |
| { |
| struct task_struct *task = ctx->ctx_task; |
| |
| ia64_psr(regs)->up = 0; |
| ia64_psr(regs)->sp = 1; |
| |
| if (GET_PMU_OWNER() == task) { |
| DPRINT(("cleared ownership for [%d]\n", ctx->ctx_task->pid)); |
| SET_PMU_OWNER(NULL, NULL); |
| } |
| |
| /* |
| * disconnect the task from the context and vice-versa |
| */ |
| PFM_SET_WORK_PENDING(task, 0); |
| |
| task->thread.pfm_context = NULL; |
| task->thread.flags &= ~IA64_THREAD_PM_VALID; |
| |
| DPRINT(("force cleanup for [%d]\n", task->pid)); |
| } |
| |
| |
| /* |
| * in 2.6, interrupts are masked when we come here and the runqueue lock is held |
| */ |
| void |
| pfm_save_regs(struct task_struct *task) |
| { |
| pfm_context_t *ctx; |
| struct thread_struct *t; |
| unsigned long flags; |
| u64 psr; |
| |
| |
| ctx = PFM_GET_CTX(task); |
| if (ctx == NULL) return; |
| t = &task->thread; |
| |
| /* |
| * we always come here with interrupts ALREADY disabled by |
| * the scheduler. So we simply need to protect against concurrent |
| * access, not CPU concurrency. |
| */ |
| flags = pfm_protect_ctx_ctxsw(ctx); |
| |
| if (ctx->ctx_state == PFM_CTX_ZOMBIE) { |
| struct pt_regs *regs = ia64_task_regs(task); |
| |
| pfm_clear_psr_up(); |
| |
| pfm_force_cleanup(ctx, regs); |
| |
| BUG_ON(ctx->ctx_smpl_hdr); |
| |
| pfm_unprotect_ctx_ctxsw(ctx, flags); |
| |
| pfm_context_free(ctx); |
| return; |
| } |
| |
| /* |
| * save current PSR: needed because we modify it |
| */ |
| ia64_srlz_d(); |
| psr = pfm_get_psr(); |
| |
| BUG_ON(psr & (IA64_PSR_I)); |
| |
| /* |
| * stop monitoring: |
| * This is the last instruction which may generate an overflow |
| * |
| * We do not need to set psr.sp because, it is irrelevant in kernel. |
| * It will be restored from ipsr when going back to user level |
| */ |
| pfm_clear_psr_up(); |
| |
| /* |
| * keep a copy of psr.up (for reload) |
| */ |
| ctx->ctx_saved_psr_up = psr & IA64_PSR_UP; |
| |
| /* |
| * release ownership of this PMU. |
| * PM interrupts are masked, so nothing |
| * can happen. |
| */ |
| SET_PMU_OWNER(NULL, NULL); |
| |
| /* |
| * we systematically save the PMD as we have no |
| * guarantee we will be schedule at that same |
| * CPU again. |
| */ |
| pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]); |
| |
| /* |
| * save pmc0 ia64_srlz_d() done in pfm_save_pmds() |
| * we will need it on the restore path to check |
| * for pending overflow. |
| */ |
| t->pmcs[0] = ia64_get_pmc(0); |
| |
| /* |
| * unfreeze PMU if had pending overflows |
| */ |
| if (t->pmcs[0] & ~0x1UL) pfm_unfreeze_pmu(); |
| |
| /* |
| * finally, allow context access. |
| * interrupts will still be masked after this call. |
| */ |
| pfm_unprotect_ctx_ctxsw(ctx, flags); |
| } |
| |
| #else /* !CONFIG_SMP */ |
| void |
| pfm_save_regs(struct task_struct *task) |
| { |
| pfm_context_t *ctx; |
| u64 psr; |
| |
| ctx = PFM_GET_CTX(task); |
| if (ctx == NULL) return; |
| |
| /* |
| * save current PSR: needed because we modify it |
| */ |
| psr = pfm_get_psr(); |
| |
| BUG_ON(psr & (IA64_PSR_I)); |
| |
| /* |
| * stop monitoring: |
| * This is the last instruction which may generate an overflow |
| * |
| * We do not need to set psr.sp because, it is irrelevant in kernel. |
| * It will be restored from ipsr when going back to user level |
| */ |
| pfm_clear_psr_up(); |
| |
| /* |
| * keep a copy of psr.up (for reload) |
| */ |
| ctx->ctx_saved_psr_up = psr & IA64_PSR_UP; |
| } |
| |
| static void |
| pfm_lazy_save_regs (struct task_struct *task) |
| { |
| pfm_context_t *ctx; |
| struct thread_struct *t; |
| unsigned long flags; |
| |
| { u64 psr = pfm_get_psr(); |
| BUG_ON(psr & IA64_PSR_UP); |
| } |
| |
| ctx = PFM_GET_CTX(task); |
| t = &task->thread; |
| |
| /* |
| * we need to mask PMU overflow here to |
| * make sure that we maintain pmc0 until |
| * we save it. overflow interrupts are |
| * treated as spurious if there is no |
| * owner. |
| * |
| * XXX: I don't think this is necessary |
| */ |
| PROTECT_CTX(ctx,flags); |
| |
| /* |
| * release ownership of this PMU. |
| * must be done before we save the registers. |
| * |
| * after this call any PMU interrupt is treated |
| * as spurious. |
| */ |
| SET_PMU_OWNER(NULL, NULL); |
| |
| /* |
| * save all the pmds we use |
| */ |
| pfm_save_pmds(t->pmds, ctx->ctx_used_pmds[0]); |
| |
| /* |
| * save pmc0 ia64_srlz_d() done in pfm_save_pmds() |
| * it is needed to check for pended overflow |
| * on the restore path |
| */ |
| t->pmcs[0] = ia64_get_pmc(0); |
| |
| /* |
| * unfreeze PMU if had pending overflows |
| */ |
| if (t->pmcs[0] & ~0x1UL) pfm_unfreeze_pmu(); |
| |
| /* |
| * now get can unmask PMU interrupts, they will |
| * be treated as purely spurious and we will not |
| * lose any information |
| */ |
| UNPROTECT_CTX(ctx,flags); |
| } |
| #endif /* CONFIG_SMP */ |
| |
| #ifdef CONFIG_SMP |
| /* |
| * in 2.6, interrupts are masked when we come here and the runqueue lock is held |
| */ |
| void |
| pfm_load_regs (struct task_struct *task) |
| { |
| pfm_context_t *ctx; |
| struct thread_struct *t; |
| unsigned long pmc_mask = 0UL, pmd_mask = 0UL; |
| unsigned long flags; |
| u64 psr, psr_up; |
| int need_irq_resend; |
| |
| ctx = PFM_GET_CTX(task); |
| if (unlikely(ctx == NULL)) return; |
| |
| BUG_ON(GET_PMU_OWNER()); |
| |
| t = &task->thread; |
| /* |
| * possible on unload |
| */ |
| if (unlikely((t->flags & IA64_THREAD_PM_VALID) == 0)) return; |
| |
| /* |
| * we always come here with interrupts ALREADY disabled by |
| * the scheduler. So we simply need to protect against concurrent |
| * access, not CPU concurrency. |
| */ |
| flags = pfm_protect_ctx_ctxsw(ctx); |
| psr = pfm_get_psr(); |
| |
| need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND; |
| |
| BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); |
| BUG_ON(psr & IA64_PSR_I); |
| |
| if (unlikely(ctx->ctx_state == PFM_CTX_ZOMBIE)) { |
| struct pt_regs *regs = ia64_task_regs(task); |
| |
| BUG_ON(ctx->ctx_smpl_hdr); |
| |
| pfm_force_cleanup(ctx, regs); |
| |
| pfm_unprotect_ctx_ctxsw(ctx, flags); |
| |
| /* |
| * this one (kmalloc'ed) is fine with interrupts disabled |
| */ |
| pfm_context_free(ctx); |
| |
| return; |
| } |
| |
| /* |
| * we restore ALL the debug registers to avoid picking up |
| * stale state. |
| */ |
| if (ctx->ctx_fl_using_dbreg) { |
| pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); |
| pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); |
| } |
| /* |
| * retrieve saved psr.up |
| */ |
| psr_up = ctx->ctx_saved_psr_up; |
| |
| /* |
| * if we were the last user of the PMU on that CPU, |
| * then nothing to do except restore psr |
| */ |
| if (GET_LAST_CPU(ctx) == smp_processor_id() && ctx->ctx_last_activation == GET_ACTIVATION()) { |
| |
| /* |
| * retrieve partial reload masks (due to user modifications) |
| */ |
| pmc_mask = ctx->ctx_reload_pmcs[0]; |
| pmd_mask = ctx->ctx_reload_pmds[0]; |
| |
| } else { |
| /* |
| * To avoid leaking information to the user level when psr.sp=0, |
| * we must reload ALL implemented pmds (even the ones we don't use). |
| * In the kernel we only allow PFM_READ_PMDS on registers which |
| * we initialized or requested (sampling) so there is no risk there. |
| */ |
| pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0]; |
| |
| /* |
| * ALL accessible PMCs are systematically reloaded, unused registers |
| * get their default (from pfm_reset_pmu_state()) values to avoid picking |
| * up stale configuration. |
| * |
| * PMC0 is never in the mask. It is always restored separately. |
| */ |
| pmc_mask = ctx->ctx_all_pmcs[0]; |
| } |
| /* |
| * when context is MASKED, we will restore PMC with plm=0 |
| * and PMD with stale information, but that's ok, nothing |
| * will be captured. |
| * |
| * XXX: optimize here |
| */ |
| if (pmd_mask) pfm_restore_pmds(t->pmds, pmd_mask); |
| if (pmc_mask) pfm_restore_pmcs(t->pmcs, pmc_mask); |
| |
| /* |
| * check for pending overflow at the time the state |
| * was saved. |
| */ |
| if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) { |
| /* |
| * reload pmc0 with the overflow information |
| * On McKinley PMU, this will trigger a PMU interrupt |
| */ |
| ia64_set_pmc(0, t->pmcs[0]); |
| ia64_srlz_d(); |
| t->pmcs[0] = 0UL; |
| |
| /* |
| * will replay the PMU interrupt |
| */ |
| if (need_irq_resend) hw_resend_irq(NULL, IA64_PERFMON_VECTOR); |
| |
| pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++; |
| } |
| |
| /* |
| * we just did a reload, so we reset the partial reload fields |
| */ |
| ctx->ctx_reload_pmcs[0] = 0UL; |
| ctx->ctx_reload_pmds[0] = 0UL; |
| |
| SET_LAST_CPU(ctx, smp_processor_id()); |
| |
| /* |
| * dump activation value for this PMU |
| */ |
| INC_ACTIVATION(); |
| /* |
| * record current activation for this context |
| */ |
| SET_ACTIVATION(ctx); |
| |
| /* |
| * establish new ownership. |
| */ |
| SET_PMU_OWNER(task, ctx); |
| |
| /* |
| * restore the psr.up bit. measurement |
| * is active again. |
| * no PMU interrupt can happen at this point |
| * because we still have interrupts disabled. |
| */ |
| if (likely(psr_up)) pfm_set_psr_up(); |
| |
| /* |
| * allow concurrent access to context |
| */ |
| pfm_unprotect_ctx_ctxsw(ctx, flags); |
| } |
| #else /* !CONFIG_SMP */ |
| /* |
| * reload PMU state for UP kernels |
| * in 2.5 we come here with interrupts disabled |
| */ |
| void |
| pfm_load_regs (struct task_struct *task) |
| { |
| struct thread_struct *t; |
| pfm_context_t *ctx; |
| struct task_struct *owner; |
| unsigned long pmd_mask, pmc_mask; |
| u64 psr, psr_up; |
| int need_irq_resend; |
| |
| owner = GET_PMU_OWNER(); |
| ctx = PFM_GET_CTX(task); |
| t = &task->thread; |
| psr = pfm_get_psr(); |
| |
| BUG_ON(psr & (IA64_PSR_UP|IA64_PSR_PP)); |
| BUG_ON(psr & IA64_PSR_I); |
| |
| /* |
| * we restore ALL the debug registers to avoid picking up |
| * stale state. |
| * |
| * This must be done even when the task is still the owner |
| * as the registers may have been modified via ptrace() |
| * (not perfmon) by the previous task. |
| */ |
| if (ctx->ctx_fl_using_dbreg) { |
| pfm_restore_ibrs(ctx->ctx_ibrs, pmu_conf->num_ibrs); |
| pfm_restore_dbrs(ctx->ctx_dbrs, pmu_conf->num_dbrs); |
| } |
| |
| /* |
| * retrieved saved psr.up |
| */ |
| psr_up = ctx->ctx_saved_psr_up; |
| need_irq_resend = pmu_conf->flags & PFM_PMU_IRQ_RESEND; |
| |
| /* |
| * short path, our state is still there, just |
| * need to restore psr and we go |
| * |
| * we do not touch either PMC nor PMD. the psr is not touched |
| * by the overflow_handler. So we are safe w.r.t. to interrupt |
| * concurrency even without interrupt masking. |
| */ |
| if (likely(owner == task)) { |
| if (likely(psr_up)) pfm_set_psr_up(); |
| return; |
| } |
| |
| /* |
| * someone else is still using the PMU, first push it out and |
| * then we'll be able to install our stuff ! |
| * |
| * Upon return, there will be no owner for the current PMU |
| */ |
| if (owner) pfm_lazy_save_regs(owner); |
| |
| /* |
| * To avoid leaking information to the user level when psr.sp=0, |
| * we must reload ALL implemented pmds (even the ones we don't use). |
| * In the kernel we only allow PFM_READ_PMDS on registers which |
| * we initialized or requested (sampling) so there is no risk there. |
| */ |
| pmd_mask = pfm_sysctl.fastctxsw ? ctx->ctx_used_pmds[0] : ctx->ctx_all_pmds[0]; |
| |
| /* |
| * ALL accessible PMCs are systematically reloaded, unused registers |
| * get their default (from pfm_reset_pmu_state()) values to avoid picking |
| * up stale configuration. |
| * |
| * PMC0 is never in the mask. It is always restored separately |
| */ |
| pmc_mask = ctx->ctx_all_pmcs[0]; |
| |
| pfm_restore_pmds(t->pmds, pmd_mask); |
| pfm_restore_pmcs(t->pmcs, pmc_mask); |
| |
| /* |
| * check for pending overflow at the time the state |
| * was saved. |
| */ |
| if (unlikely(PMC0_HAS_OVFL(t->pmcs[0]))) { |
| /* |
| * reload pmc0 with the overflow information |
| * On McKinley PMU, this will trigger a PMU interrupt |
| */ |
| ia64_set_pmc(0, t->pmcs[0]); |
| ia64_srlz_d(); |
| |
| t->pmcs[0] = 0UL; |
| |
| /* |
| * will replay the PMU interrupt |
| */ |
| if (need_irq_resend) hw_resend_irq(NULL, IA64_PERFMON_VECTOR); |
| |
| pfm_stats[smp_processor_id()].pfm_replay_ovfl_intr_count++; |
| } |
| |
| /* |
| * establish new ownership. |
| */ |
| SET_PMU_OWNER(task, ctx); |
| |
| /* |
| * restore the psr.up bit. measurement |
| * is active again. |
| * no PMU interrupt can happen at this point |
| * because we still have interrupts disabled. |
| */ |
| if (likely(psr_up)) pfm_set_psr_up(); |
| } |
| #endif /* CONFIG_SMP */ |
| |
| /* |
| * this function assumes monitoring is stopped |
| */ |
| static void |
| pfm_flush_pmds(struct task_struct *task, pfm_context_t *ctx) |
| { |
| u64 pmc0; |
| unsigned long mask2, val, pmd_val, ovfl_val; |
| int i, can_access_pmu = 0; |
| int is_self; |
| |
| /* |
| * is the caller the task being monitored (or which initiated the |
| * session for system wide measurements) |
| */ |
| is_self = ctx->ctx_task == task ? 1 : 0; |
| |
| /* |
| * can access PMU is task is the owner of the PMU state on the current CPU |
| * or if we are running on the CPU bound to the context in system-wide mode |
| * (that is not necessarily the task the context is attached to in this mode). |
| * In system-wide we always have can_access_pmu true because a task running on an |
| * invalid processor is flagged earlier in the call stack (see pfm_stop). |
| */ |
| can_access_pmu = (GET_PMU_OWNER() == task) || (ctx->ctx_fl_system && ctx->ctx_cpu == smp_processor_id()); |
| if (can_access_pmu) { |
| /* |
| * Mark the PMU as not owned |
| * This will cause the interrupt handler to do nothing in case an overflow |
| * interrupt was in-flight |
| * This also guarantees that pmc0 will contain the final state |
| * It virtually gives us full control on overflow processing from that point |
| * on. |
| */ |
| SET_PMU_OWNER(NULL, NULL); |
| DPRINT(("releasing ownership\n")); |
| |
| /* |
| * read current overflow status: |
| * |
| * we are guaranteed to read the final stable state |
| */ |
| ia64_srlz_d(); |
| pmc0 = ia64_get_pmc(0); /* slow */ |
| |
| /* |
| * reset freeze bit, overflow status information destroyed |
| */ |
| pfm_unfreeze_pmu(); |
| } else { |
| pmc0 = task->thread.pmcs[0]; |
| /* |
| * clear whatever overflow status bits there were |
| */ |
| task->thread.pmcs[0] = 0; |
| } |
| ovfl_val = pmu_conf->ovfl_val; |
| /* |
| * we save all the used pmds |
| * we take care of overflows for counting PMDs |
| * |
| * XXX: sampling situation is not taken into account here |
| */ |
| mask2 = ctx->ctx_used_pmds[0]; |
| |
| DPRINT(("is_self=%d ovfl_val=0x%lx mask2=0x%lx\n", is_self, ovfl_val, mask2)); |
| |
| for (i = 0; mask2; i++, mask2>>=1) { |
| |
| /* skip non used pmds */ |
| if ((mask2 & 0x1) == 0) continue; |
| |
| /* |
| * can access PMU always true in system wide mode |
| */ |
| val = pmd_val = can_access_pmu ? ia64_get_pmd(i) : task->thread.pmds[i]; |
| |
| if (PMD_IS_COUNTING(i)) { |
| DPRINT(("[%d] pmd[%d] ctx_pmd=0x%lx hw_pmd=0x%lx\n", |
| task->pid, |
| i, |
| ctx->ctx_pmds[i].val, |
| val & ovfl_val)); |
| |
| /* |
| * we rebuild the full 64 bit value of the counter |
| */ |
| val = ctx->ctx_pmds[i].val + (val & ovfl_val); |
| |
| /* |
| * now everything is in ctx_pmds[] and we need |
| * to clear the saved context from save_regs() such that |
| * pfm_read_pmds() gets the correct value |
| */ |
| pmd_val = 0UL; |
| |
| /* |
| * take care of overflow inline |
| */ |
| if (pmc0 & (1UL << i)) { |
| val += 1 + ovfl_val; |
| DPRINT(("[%d] pmd[%d] overflowed\n", task->pid, i)); |
| } |
| } |
| |
| DPRINT(("[%d] ctx_pmd[%d]=0x%lx pmd_val=0x%lx\n", task->pid, i, val, pmd_val)); |
| |
| if (is_self) task->thread.pmds[i] = pmd_val; |
| |
| ctx->ctx_pmds[i].val = val; |
| } |
| } |
| |
| static struct irqaction perfmon_irqaction = { |
| .handler = pfm_interrupt_handler, |
| .flags = SA_INTERRUPT, |
| .name = "perfmon" |
| }; |
| |
| static void |
| pfm_alt_save_pmu_state(void *data) |
| { |
| struct pt_regs *regs; |
| |
| regs = ia64_task_regs(current); |
| |
| DPRINT(("called\n")); |
| |
| /* |
| * should not be necessary but |
| * let's take not risk |
| */ |
| pfm_clear_psr_up(); |
| pfm_clear_psr_pp(); |
| ia64_psr(regs)->pp = 0; |
| |
| /* |
| * This call is required |
| * May cause a spurious interrupt on some processors |
| */ |
| pfm_freeze_pmu(); |
| |
| ia64_srlz_d(); |
| } |
| |
| void |
| pfm_alt_restore_pmu_state(void *data) |
| { |
| struct pt_regs *regs; |
| |
| regs = ia64_task_regs(current); |
| |
| DPRINT(("called\n")); |
| |
| /* |
| * put PMU back in state expected |
| * by perfmon |
| */ |
| pfm_clear_psr_up(); |
| pfm_clear_psr_pp(); |
| ia64_psr(regs)->pp = 0; |
| |
| /* |
| * perfmon runs with PMU unfrozen at all times |
| */ |
| pfm_unfreeze_pmu(); |
| |
| ia64_srlz_d(); |
| } |
| |
| int |
| pfm_install_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl) |
| { |
| int ret, i; |
| int reserve_cpu; |
| |
| /* some sanity checks */ |
| if (hdl == NULL || hdl->handler == NULL) return -EINVAL; |
| |
| /* do the easy test first */ |
| if (pfm_alt_intr_handler) return -EBUSY; |
| |
| /* one at a time in the install or remove, just fail the others */ |
| if (!spin_trylock(&pfm_alt_install_check)) { |
| return -EBUSY; |
| } |
| |
| /* reserve our session */ |
| for_each_online_cpu(reserve_cpu) { |
| ret = pfm_reserve_session(NULL, 1, reserve_cpu); |
| if (ret) goto cleanup_reserve; |
| } |
| |
| /* save the current system wide pmu states */ |
| ret = on_each_cpu(pfm_alt_save_pmu_state, NULL, 0, 1); |
| if (ret) { |
| DPRINT(("on_each_cpu() failed: %d\n", ret)); |
| goto cleanup_reserve; |
| } |
| |
| /* officially change to the alternate interrupt handler */ |
| pfm_alt_intr_handler = hdl; |
| |
| spin_unlock(&pfm_alt_install_check); |
| |
| return 0; |
| |
| cleanup_reserve: |
| for_each_online_cpu(i) { |
| /* don't unreserve more than we reserved */ |
| if (i >= reserve_cpu) break; |
| |
| pfm_unreserve_session(NULL, 1, i); |
| } |
| |
| spin_unlock(&pfm_alt_install_check); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(pfm_install_alt_pmu_interrupt); |
| |
| int |
| pfm_remove_alt_pmu_interrupt(pfm_intr_handler_desc_t *hdl) |
| { |
| int i; |
| int ret; |
| |
| if (hdl == NULL) return -EINVAL; |
| |
| /* cannot remove someone else's handler! */ |
| if (pfm_alt_intr_handler != hdl) return -EINVAL; |
| |
| /* one at a time in the install or remove, just fail the others */ |
| if (!spin_trylock(&pfm_alt_install_check)) { |
| return -EBUSY; |
| } |
| |
| pfm_alt_intr_handler = NULL; |
| |
| ret = on_each_cpu(pfm_alt_restore_pmu_state, NULL, 0, 1); |
| if (ret) { |
| DPRINT(("on_each_cpu() failed: %d\n", ret)); |
| } |
| |
| for_each_online_cpu(i) { |
| pfm_unreserve_session(NULL, 1, i); |
| } |
| |
| spin_unlock(&pfm_alt_install_check); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(pfm_remove_alt_pmu_interrupt); |
| |
| /* |
| * perfmon initialization routine, called from the initcall() table |
| */ |
| static int init_pfm_fs(void); |
| |
| static int __init |
| pfm_probe_pmu(void) |
| { |
| pmu_config_t **p; |
| int family; |
| |
| family = local_cpu_data->family; |
| p = pmu_confs; |
| |
| while(*p) { |
| if ((*p)->probe) { |
| if ((*p)->probe() == 0) goto found; |
| } else if ((*p)->pmu_family == family || (*p)->pmu_family == 0xff) { |
| goto found; |
| } |
| p++; |
| } |
| return -1; |
| found: |
| pmu_conf = *p; |
| return 0; |
| } |
| |
| static struct file_operations pfm_proc_fops = { |
| .open = pfm_proc_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| int __init |
| pfm_init(void) |
| { |
| unsigned int n, n_counters, i; |
| |
| printk("perfmon: version %u.%u IRQ %u\n", |
| PFM_VERSION_MAJ, |
| PFM_VERSION_MIN, |
| IA64_PERFMON_VECTOR); |
| |
| if (pfm_probe_pmu()) { |
| printk(KERN_INFO "perfmon: disabled, there is no support for processor family %d\n", |
| local_cpu_data->family); |
| return -ENODEV; |
| } |
| |
| /* |
| * compute the number of implemented PMD/PMC from the |
| * description tables |
| */ |
| n = 0; |
| for (i=0; PMC_IS_LAST(i) == 0; i++) { |
| if (PMC_IS_IMPL(i) == 0) continue; |
| pmu_conf->impl_pmcs[i>>6] |= 1UL << (i&63); |
| n++; |
| } |
| pmu_conf->num_pmcs = n; |
| |
| n = 0; n_counters = 0; |
| for (i=0; PMD_IS_LAST(i) == 0; i++) { |
| if (PMD_IS_IMPL(i) == 0) continue; |
| pmu_conf->impl_pmds[i>>6] |= 1UL << (i&63); |
| n++; |
| if (PMD_IS_COUNTING(i)) n_counters++; |
| } |
| pmu_conf->num_pmds = n; |
| pmu_conf->num_counters = n_counters; |
| |
| /* |
| * sanity checks on the number of debug registers |
| */ |
| if (pmu_conf->use_rr_dbregs) { |
| if (pmu_conf->num_ibrs > IA64_NUM_DBG_REGS) { |
| printk(KERN_INFO "perfmon: unsupported number of code debug registers (%u)\n", pmu_conf->num_ibrs); |
| pmu_conf = NULL; |
| return -1; |
| } |
| if (pmu_conf->num_dbrs > IA64_NUM_DBG_REGS) { |
| printk(KERN_INFO "perfmon: unsupported number of data debug registers (%u)\n", pmu_conf->num_ibrs); |
| pmu_conf = NULL; |
| return -1; |
| } |
| } |
| |
| printk("perfmon: %s PMU detected, %u PMCs, %u PMDs, %u counters (%lu bits)\n", |
| pmu_conf->pmu_name, |
| pmu_conf->num_pmcs, |
| pmu_conf->num_pmds, |
| pmu_conf->num_counters, |
| ffz(pmu_conf->ovfl_val)); |
| |
| /* sanity check */ |
| if (pmu_conf->num_pmds >= IA64_NUM_PMD_REGS || pmu_conf->num_pmcs >= IA64_NUM_PMC_REGS) { |
| printk(KERN_ERR "perfmon: not enough pmc/pmd, perfmon disabled\n"); |
| pmu_conf = NULL; |
| return -1; |
| } |
| |
| /* |
| * create /proc/perfmon (mostly for debugging purposes) |
| */ |
| perfmon_dir = create_proc_entry("perfmon", S_IRUGO, NULL); |
| if (perfmon_dir == NULL) { |
| printk(KERN_ERR "perfmon: cannot create /proc entry, perfmon disabled\n"); |
| pmu_conf = NULL; |
| return -1; |
| } |
| /* |
| * install customized file operations for /proc/perfmon entry |
| */ |
| perfmon_dir->proc_fops = &pfm_proc_fops; |
| |
| /* |
| * create /proc/sys/kernel/perfmon (for debugging purposes) |
| */ |
| pfm_sysctl_header = register_sysctl_table(pfm_sysctl_root, 0); |
| |
| /* |
| * initialize all our spinlocks |
| */ |
| spin_lock_init(&pfm_sessions.pfs_lock); |
| spin_lock_init(&pfm_buffer_fmt_lock); |
| |
| init_pfm_fs(); |
| |
| for(i=0; i < NR_CPUS; i++) pfm_stats[i].pfm_ovfl_intr_cycles_min = ~0UL; |
| |
| return 0; |
| } |
| |
| __initcall(pfm_init); |
| |
| /* |
| * this function is called before pfm_init() |
| */ |
| void |
| pfm_init_percpu (void) |
| { |
| /* |
| * make sure no measurement is active |
| * (may inherit programmed PMCs from EFI). |
| */ |
| pfm_clear_psr_pp(); |
| pfm_clear_psr_up(); |
| |
| /* |
| * we run with the PMU not frozen at all times |
| */ |
| pfm_unfreeze_pmu(); |
| |
| if (smp_processor_id() == 0) |
| register_percpu_irq(IA64_PERFMON_VECTOR, &perfmon_irqaction); |
| |
| ia64_setreg(_IA64_REG_CR_PMV, IA64_PERFMON_VECTOR); |
| ia64_srlz_d(); |
| } |
| |
| /* |
| * used for debug purposes only |
| */ |
| void |
| dump_pmu_state(const char *from) |
| { |
| struct task_struct *task; |
| struct thread_struct *t; |
| struct pt_regs *regs; |
| pfm_context_t *ctx; |
| unsigned long psr, dcr, info, flags; |
| int i, this_cpu; |
| |
| local_irq_save(flags); |
| |
| this_cpu = smp_processor_id(); |
| regs = ia64_task_regs(current); |
| info = PFM_CPUINFO_GET(); |
| dcr = ia64_getreg(_IA64_REG_CR_DCR); |
| |
| if (info == 0 && ia64_psr(regs)->pp == 0 && (dcr & IA64_DCR_PP) == 0) { |
| local_irq_restore(flags); |
| return; |
| } |
| |
| printk("CPU%d from %s() current [%d] iip=0x%lx %s\n", |
| this_cpu, |
| from, |
| current->pid, |
| regs->cr_iip, |
| current->comm); |
| |
| task = GET_PMU_OWNER(); |
| ctx = GET_PMU_CTX(); |
| |
| printk("->CPU%d owner [%d] ctx=%p\n", this_cpu, task ? task->pid : -1, ctx); |
| |
| psr = pfm_get_psr(); |
| |
| printk("->CPU%d pmc0=0x%lx psr.pp=%d psr.up=%d dcr.pp=%d syst_info=0x%lx user_psr.up=%d user_psr.pp=%d\n", |
| this_cpu, |
| ia64_get_pmc(0), |
| psr & IA64_PSR_PP ? 1 : 0, |
| psr & IA64_PSR_UP ? 1 : 0, |
| dcr & IA64_DCR_PP ? 1 : 0, |
| info, |
| ia64_psr(regs)->up, |
| ia64_psr(regs)->pp); |
| |
| ia64_psr(regs)->up = 0; |
| ia64_psr(regs)->pp = 0; |
| |
| t = ¤t->thread; |
| |
| for (i=1; PMC_IS_LAST(i) == 0; i++) { |
| if (PMC_IS_IMPL(i) == 0) continue; |
| printk("->CPU%d pmc[%d]=0x%lx thread_pmc[%d]=0x%lx\n", this_cpu, i, ia64_get_pmc(i), i, t->pmcs[i]); |
| } |
| |
| for (i=1; PMD_IS_LAST(i) == 0; i++) { |
| if (PMD_IS_IMPL(i) == 0) continue; |
| printk("->CPU%d pmd[%d]=0x%lx thread_pmd[%d]=0x%lx\n", this_cpu, i, ia64_get_pmd(i), i, t->pmds[i]); |
| } |
| |
| if (ctx) { |
| printk("->CPU%d ctx_state=%d vaddr=%p addr=%p fd=%d ctx_task=[%d] saved_psr_up=0x%lx\n", |
| this_cpu, |
| ctx->ctx_state, |
| ctx->ctx_smpl_vaddr, |
| ctx->ctx_smpl_hdr, |
| ctx->ctx_msgq_head, |
| ctx->ctx_msgq_tail, |
| ctx->ctx_saved_psr_up); |
| } |
| local_irq_restore(flags); |
| } |
| |
| /* |
| * called from process.c:copy_thread(). task is new child. |
| */ |
| void |
| pfm_inherit(struct task_struct *task, struct pt_regs *regs) |
| { |
| struct thread_struct *thread; |
| |
| DPRINT(("perfmon: pfm_inherit clearing state for [%d]\n", task->pid)); |
| |
| thread = &task->thread; |
| |
| /* |
| * cut links inherited from parent (current) |
| */ |
| thread->pfm_context = NULL; |
| |
| PFM_SET_WORK_PENDING(task, 0); |
| |
| /* |
| * the psr bits are already set properly in copy_threads() |
| */ |
| } |
| #else /* !CONFIG_PERFMON */ |
| asmlinkage long |
| sys_perfmonctl (int fd, int cmd, void *arg, int count) |
| { |
| return -ENOSYS; |
| } |
| #endif /* CONFIG_PERFMON */ |