blob: f380d91ee609779b9b8234a9316d72f98cb2d48b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
#include "builtin.h"
#include "perf.h"
#include "util/util.h"
#include "util/evlist.h"
#include "util/cache.h"
#include "util/evsel.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/cloexec.h"
#include "util/thread_map.h"
#include "util/color.h"
#include "util/stat.h"
#include "util/callchain.h"
#include "util/time-utils.h"
#include <subcmd/parse-options.h>
#include "util/trace-event.h"
#include "util/debug.h"
#include <linux/kernel.h>
#include <linux/log2.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <inttypes.h>
#include <errno.h>
#include <semaphore.h>
#include <pthread.h>
#include <math.h>
#include <api/fs/fs.h>
#include <linux/time64.h>
#include "sane_ctype.h"
#define PR_SET_NAME 15 /* Set process name */
#define MAX_CPUS 4096
#define COMM_LEN 20
#define SYM_LEN 129
#define MAX_PID 1024000
struct sched_atom;
struct task_desc {
unsigned long nr;
unsigned long pid;
char comm[COMM_LEN];
unsigned long nr_events;
unsigned long curr_event;
struct sched_atom **atoms;
pthread_t thread;
sem_t sleep_sem;
sem_t ready_for_work;
sem_t work_done_sem;
u64 cpu_usage;
};
enum sched_event_type {
SCHED_EVENT_RUN,
SCHED_EVENT_SLEEP,
SCHED_EVENT_WAKEUP,
SCHED_EVENT_MIGRATION,
};
struct sched_atom {
enum sched_event_type type;
int specific_wait;
u64 timestamp;
u64 duration;
unsigned long nr;
sem_t *wait_sem;
struct task_desc *wakee;
};
#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKWP"
/* task state bitmask, copied from include/linux/sched.h */
#define TASK_RUNNING 0
#define TASK_INTERRUPTIBLE 1
#define TASK_UNINTERRUPTIBLE 2
#define __TASK_STOPPED 4
#define __TASK_TRACED 8
/* in tsk->exit_state */
#define EXIT_DEAD 16
#define EXIT_ZOMBIE 32
#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
/* in tsk->state again */
#define TASK_DEAD 64
#define TASK_WAKEKILL 128
#define TASK_WAKING 256
#define TASK_PARKED 512
enum thread_state {
THREAD_SLEEPING = 0,
THREAD_WAIT_CPU,
THREAD_SCHED_IN,
THREAD_IGNORE
};
struct work_atom {
struct list_head list;
enum thread_state state;
u64 sched_out_time;
u64 wake_up_time;
u64 sched_in_time;
u64 runtime;
};
struct work_atoms {
struct list_head work_list;
struct thread *thread;
struct rb_node node;
u64 max_lat;
u64 max_lat_at;
u64 total_lat;
u64 nb_atoms;
u64 total_runtime;
int num_merged;
};
typedef int (*sort_fn_t)(struct work_atoms *, struct work_atoms *);
struct perf_sched;
struct trace_sched_handler {
int (*switch_event)(struct perf_sched *sched, struct perf_evsel *evsel,
struct perf_sample *sample, struct machine *machine);
int (*runtime_event)(struct perf_sched *sched, struct perf_evsel *evsel,
struct perf_sample *sample, struct machine *machine);
int (*wakeup_event)(struct perf_sched *sched, struct perf_evsel *evsel,
struct perf_sample *sample, struct machine *machine);
/* PERF_RECORD_FORK event, not sched_process_fork tracepoint */
int (*fork_event)(struct perf_sched *sched, union perf_event *event,
struct machine *machine);
int (*migrate_task_event)(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine);
};
#define COLOR_PIDS PERF_COLOR_BLUE
#define COLOR_CPUS PERF_COLOR_BG_RED
struct perf_sched_map {
DECLARE_BITMAP(comp_cpus_mask, MAX_CPUS);
int *comp_cpus;
bool comp;
struct thread_map *color_pids;
const char *color_pids_str;
struct cpu_map *color_cpus;
const char *color_cpus_str;
struct cpu_map *cpus;
const char *cpus_str;
};
struct perf_sched {
struct perf_tool tool;
const char *sort_order;
unsigned long nr_tasks;
struct task_desc **pid_to_task;
struct task_desc **tasks;
const struct trace_sched_handler *tp_handler;
pthread_mutex_t start_work_mutex;
pthread_mutex_t work_done_wait_mutex;
int profile_cpu;
/*
* Track the current task - that way we can know whether there's any
* weird events, such as a task being switched away that is not current.
*/
int max_cpu;
u32 curr_pid[MAX_CPUS];
struct thread *curr_thread[MAX_CPUS];
char next_shortname1;
char next_shortname2;
unsigned int replay_repeat;
unsigned long nr_run_events;
unsigned long nr_sleep_events;
unsigned long nr_wakeup_events;
unsigned long nr_sleep_corrections;
unsigned long nr_run_events_optimized;
unsigned long targetless_wakeups;
unsigned long multitarget_wakeups;
unsigned long nr_runs;
unsigned long nr_timestamps;
unsigned long nr_unordered_timestamps;
unsigned long nr_context_switch_bugs;
unsigned long nr_events;
unsigned long nr_lost_chunks;
unsigned long nr_lost_events;
u64 run_measurement_overhead;
u64 sleep_measurement_overhead;
u64 start_time;
u64 cpu_usage;
u64 runavg_cpu_usage;
u64 parent_cpu_usage;
u64 runavg_parent_cpu_usage;
u64 sum_runtime;
u64 sum_fluct;
u64 run_avg;
u64 all_runtime;
u64 all_count;
u64 cpu_last_switched[MAX_CPUS];
struct rb_root atom_root, sorted_atom_root, merged_atom_root;
struct list_head sort_list, cmp_pid;
bool force;
bool skip_merge;
struct perf_sched_map map;
/* options for timehist command */
bool summary;
bool summary_only;
bool idle_hist;
bool show_callchain;
unsigned int max_stack;
bool show_cpu_visual;
bool show_wakeups;
bool show_next;
bool show_migrations;
bool show_state;
u64 skipped_samples;
const char *time_str;
struct perf_time_interval ptime;
struct perf_time_interval hist_time;
};
/* per thread run time data */
struct thread_runtime {
u64 last_time; /* time of previous sched in/out event */
u64 dt_run; /* run time */
u64 dt_sleep; /* time between CPU access by sleep (off cpu) */
u64 dt_iowait; /* time between CPU access by iowait (off cpu) */
u64 dt_preempt; /* time between CPU access by preempt (off cpu) */
u64 dt_delay; /* time between wakeup and sched-in */
u64 ready_to_run; /* time of wakeup */
struct stats run_stats;
u64 total_run_time;
u64 total_sleep_time;
u64 total_iowait_time;
u64 total_preempt_time;
u64 total_delay_time;
int last_state;
u64 migrations;
};
/* per event run time data */
struct evsel_runtime {
u64 *last_time; /* time this event was last seen per cpu */
u32 ncpu; /* highest cpu slot allocated */
};
/* per cpu idle time data */
struct idle_thread_runtime {
struct thread_runtime tr;
struct thread *last_thread;
struct rb_root sorted_root;
struct callchain_root callchain;
struct callchain_cursor cursor;
};
/* track idle times per cpu */
static struct thread **idle_threads;
static int idle_max_cpu;
static char idle_comm[] = "<idle>";
static u64 get_nsecs(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec;
}
static void burn_nsecs(struct perf_sched *sched, u64 nsecs)
{
u64 T0 = get_nsecs(), T1;
do {
T1 = get_nsecs();
} while (T1 + sched->run_measurement_overhead < T0 + nsecs);
}
static void sleep_nsecs(u64 nsecs)
{
struct timespec ts;
ts.tv_nsec = nsecs % 999999999;
ts.tv_sec = nsecs / 999999999;
nanosleep(&ts, NULL);
}
static void calibrate_run_measurement_overhead(struct perf_sched *sched)
{
u64 T0, T1, delta, min_delta = NSEC_PER_SEC;
int i;
for (i = 0; i < 10; i++) {
T0 = get_nsecs();
burn_nsecs(sched, 0);
T1 = get_nsecs();
delta = T1-T0;
min_delta = min(min_delta, delta);
}
sched->run_measurement_overhead = min_delta;
printf("run measurement overhead: %" PRIu64 " nsecs\n", min_delta);
}
static void calibrate_sleep_measurement_overhead(struct perf_sched *sched)
{
u64 T0, T1, delta, min_delta = NSEC_PER_SEC;
int i;
for (i = 0; i < 10; i++) {
T0 = get_nsecs();
sleep_nsecs(10000);
T1 = get_nsecs();
delta = T1-T0;
min_delta = min(min_delta, delta);
}
min_delta -= 10000;
sched->sleep_measurement_overhead = min_delta;
printf("sleep measurement overhead: %" PRIu64 " nsecs\n", min_delta);
}
static struct sched_atom *
get_new_event(struct task_desc *task, u64 timestamp)
{
struct sched_atom *event = zalloc(sizeof(*event));
unsigned long idx = task->nr_events;
size_t size;
event->timestamp = timestamp;
event->nr = idx;
task->nr_events++;
size = sizeof(struct sched_atom *) * task->nr_events;
task->atoms = realloc(task->atoms, size);
BUG_ON(!task->atoms);
task->atoms[idx] = event;
return event;
}
static struct sched_atom *last_event(struct task_desc *task)
{
if (!task->nr_events)
return NULL;
return task->atoms[task->nr_events - 1];
}
static void add_sched_event_run(struct perf_sched *sched, struct task_desc *task,
u64 timestamp, u64 duration)
{
struct sched_atom *event, *curr_event = last_event(task);
/*
* optimize an existing RUN event by merging this one
* to it:
*/
if (curr_event && curr_event->type == SCHED_EVENT_RUN) {
sched->nr_run_events_optimized++;
curr_event->duration += duration;
return;
}
event = get_new_event(task, timestamp);
event->type = SCHED_EVENT_RUN;
event->duration = duration;
sched->nr_run_events++;
}
static void add_sched_event_wakeup(struct perf_sched *sched, struct task_desc *task,
u64 timestamp, struct task_desc *wakee)
{
struct sched_atom *event, *wakee_event;
event = get_new_event(task, timestamp);
event->type = SCHED_EVENT_WAKEUP;
event->wakee = wakee;
wakee_event = last_event(wakee);
if (!wakee_event || wakee_event->type != SCHED_EVENT_SLEEP) {
sched->targetless_wakeups++;
return;
}
if (wakee_event->wait_sem) {
sched->multitarget_wakeups++;
return;
}
wakee_event->wait_sem = zalloc(sizeof(*wakee_event->wait_sem));
sem_init(wakee_event->wait_sem, 0, 0);
wakee_event->specific_wait = 1;
event->wait_sem = wakee_event->wait_sem;
sched->nr_wakeup_events++;
}
static void add_sched_event_sleep(struct perf_sched *sched, struct task_desc *task,
u64 timestamp, u64 task_state __maybe_unused)
{
struct sched_atom *event = get_new_event(task, timestamp);
event->type = SCHED_EVENT_SLEEP;
sched->nr_sleep_events++;
}
static struct task_desc *register_pid(struct perf_sched *sched,
unsigned long pid, const char *comm)
{
struct task_desc *task;
static int pid_max;
if (sched->pid_to_task == NULL) {
if (sysctl__read_int("kernel/pid_max", &pid_max) < 0)
pid_max = MAX_PID;
BUG_ON((sched->pid_to_task = calloc(pid_max, sizeof(struct task_desc *))) == NULL);
}
if (pid >= (unsigned long)pid_max) {
BUG_ON((sched->pid_to_task = realloc(sched->pid_to_task, (pid + 1) *
sizeof(struct task_desc *))) == NULL);
while (pid >= (unsigned long)pid_max)
sched->pid_to_task[pid_max++] = NULL;
}
task = sched->pid_to_task[pid];
if (task)
return task;
task = zalloc(sizeof(*task));
task->pid = pid;
task->nr = sched->nr_tasks;
strcpy(task->comm, comm);
/*
* every task starts in sleeping state - this gets ignored
* if there's no wakeup pointing to this sleep state:
*/
add_sched_event_sleep(sched, task, 0, 0);
sched->pid_to_task[pid] = task;
sched->nr_tasks++;
sched->tasks = realloc(sched->tasks, sched->nr_tasks * sizeof(struct task_desc *));
BUG_ON(!sched->tasks);
sched->tasks[task->nr] = task;
if (verbose > 0)
printf("registered task #%ld, PID %ld (%s)\n", sched->nr_tasks, pid, comm);
return task;
}
static void print_task_traces(struct perf_sched *sched)
{
struct task_desc *task;
unsigned long i;
for (i = 0; i < sched->nr_tasks; i++) {
task = sched->tasks[i];
printf("task %6ld (%20s:%10ld), nr_events: %ld\n",
task->nr, task->comm, task->pid, task->nr_events);
}
}
static void add_cross_task_wakeups(struct perf_sched *sched)
{
struct task_desc *task1, *task2;
unsigned long i, j;
for (i = 0; i < sched->nr_tasks; i++) {
task1 = sched->tasks[i];
j = i + 1;
if (j == sched->nr_tasks)
j = 0;
task2 = sched->tasks[j];
add_sched_event_wakeup(sched, task1, 0, task2);
}
}
static void perf_sched__process_event(struct perf_sched *sched,
struct sched_atom *atom)
{
int ret = 0;
switch (atom->type) {
case SCHED_EVENT_RUN:
burn_nsecs(sched, atom->duration);
break;
case SCHED_EVENT_SLEEP:
if (atom->wait_sem)
ret = sem_wait(atom->wait_sem);
BUG_ON(ret);
break;
case SCHED_EVENT_WAKEUP:
if (atom->wait_sem)
ret = sem_post(atom->wait_sem);
BUG_ON(ret);
break;
case SCHED_EVENT_MIGRATION:
break;
default:
BUG_ON(1);
}
}
static u64 get_cpu_usage_nsec_parent(void)
{
struct rusage ru;
u64 sum;
int err;
err = getrusage(RUSAGE_SELF, &ru);
BUG_ON(err);
sum = ru.ru_utime.tv_sec * NSEC_PER_SEC + ru.ru_utime.tv_usec * NSEC_PER_USEC;
sum += ru.ru_stime.tv_sec * NSEC_PER_SEC + ru.ru_stime.tv_usec * NSEC_PER_USEC;
return sum;
}
static int self_open_counters(struct perf_sched *sched, unsigned long cur_task)
{
struct perf_event_attr attr;
char sbuf[STRERR_BUFSIZE], info[STRERR_BUFSIZE];
int fd;
struct rlimit limit;
bool need_privilege = false;
memset(&attr, 0, sizeof(attr));
attr.type = PERF_TYPE_SOFTWARE;
attr.config = PERF_COUNT_SW_TASK_CLOCK;
force_again:
fd = sys_perf_event_open(&attr, 0, -1, -1,
perf_event_open_cloexec_flag());
if (fd < 0) {
if (errno == EMFILE) {
if (sched->force) {
BUG_ON(getrlimit(RLIMIT_NOFILE, &limit) == -1);
limit.rlim_cur += sched->nr_tasks - cur_task;
if (limit.rlim_cur > limit.rlim_max) {
limit.rlim_max = limit.rlim_cur;
need_privilege = true;
}
if (setrlimit(RLIMIT_NOFILE, &limit) == -1) {
if (need_privilege && errno == EPERM)
strcpy(info, "Need privilege\n");
} else
goto force_again;
} else
strcpy(info, "Have a try with -f option\n");
}
pr_err("Error: sys_perf_event_open() syscall returned "
"with %d (%s)\n%s", fd,
str_error_r(errno, sbuf, sizeof(sbuf)), info);
exit(EXIT_FAILURE);
}
return fd;
}
static u64 get_cpu_usage_nsec_self(int fd)
{
u64 runtime;
int ret;
ret = read(fd, &runtime, sizeof(runtime));
BUG_ON(ret != sizeof(runtime));
return runtime;
}
struct sched_thread_parms {
struct task_desc *task;
struct perf_sched *sched;
int fd;
};
static void *thread_func(void *ctx)
{
struct sched_thread_parms *parms = ctx;
struct task_desc *this_task = parms->task;
struct perf_sched *sched = parms->sched;
u64 cpu_usage_0, cpu_usage_1;
unsigned long i, ret;
char comm2[22];
int fd = parms->fd;
zfree(&parms);
sprintf(comm2, ":%s", this_task->comm);
prctl(PR_SET_NAME, comm2);
if (fd < 0)
return NULL;
again:
ret = sem_post(&this_task->ready_for_work);
BUG_ON(ret);
ret = pthread_mutex_lock(&sched->start_work_mutex);
BUG_ON(ret);
ret = pthread_mutex_unlock(&sched->start_work_mutex);
BUG_ON(ret);
cpu_usage_0 = get_cpu_usage_nsec_self(fd);
for (i = 0; i < this_task->nr_events; i++) {
this_task->curr_event = i;
perf_sched__process_event(sched, this_task->atoms[i]);
}
cpu_usage_1 = get_cpu_usage_nsec_self(fd);
this_task->cpu_usage = cpu_usage_1 - cpu_usage_0;
ret = sem_post(&this_task->work_done_sem);
BUG_ON(ret);
ret = pthread_mutex_lock(&sched->work_done_wait_mutex);
BUG_ON(ret);
ret = pthread_mutex_unlock(&sched->work_done_wait_mutex);
BUG_ON(ret);
goto again;
}
static void create_tasks(struct perf_sched *sched)
{
struct task_desc *task;
pthread_attr_t attr;
unsigned long i;
int err;
err = pthread_attr_init(&attr);
BUG_ON(err);
err = pthread_attr_setstacksize(&attr,
(size_t) max(16 * 1024, PTHREAD_STACK_MIN));
BUG_ON(err);
err = pthread_mutex_lock(&sched->start_work_mutex);
BUG_ON(err);
err = pthread_mutex_lock(&sched->work_done_wait_mutex);
BUG_ON(err);
for (i = 0; i < sched->nr_tasks; i++) {
struct sched_thread_parms *parms = malloc(sizeof(*parms));
BUG_ON(parms == NULL);
parms->task = task = sched->tasks[i];
parms->sched = sched;
parms->fd = self_open_counters(sched, i);
sem_init(&task->sleep_sem, 0, 0);
sem_init(&task->ready_for_work, 0, 0);
sem_init(&task->work_done_sem, 0, 0);
task->curr_event = 0;
err = pthread_create(&task->thread, &attr, thread_func, parms);
BUG_ON(err);
}
}
static void wait_for_tasks(struct perf_sched *sched)
{
u64 cpu_usage_0, cpu_usage_1;
struct task_desc *task;
unsigned long i, ret;
sched->start_time = get_nsecs();
sched->cpu_usage = 0;
pthread_mutex_unlock(&sched->work_done_wait_mutex);
for (i = 0; i < sched->nr_tasks; i++) {
task = sched->tasks[i];
ret = sem_wait(&task->ready_for_work);
BUG_ON(ret);
sem_init(&task->ready_for_work, 0, 0);
}
ret = pthread_mutex_lock(&sched->work_done_wait_mutex);
BUG_ON(ret);
cpu_usage_0 = get_cpu_usage_nsec_parent();
pthread_mutex_unlock(&sched->start_work_mutex);
for (i = 0; i < sched->nr_tasks; i++) {
task = sched->tasks[i];
ret = sem_wait(&task->work_done_sem);
BUG_ON(ret);
sem_init(&task->work_done_sem, 0, 0);
sched->cpu_usage += task->cpu_usage;
task->cpu_usage = 0;
}
cpu_usage_1 = get_cpu_usage_nsec_parent();
if (!sched->runavg_cpu_usage)
sched->runavg_cpu_usage = sched->cpu_usage;
sched->runavg_cpu_usage = (sched->runavg_cpu_usage * (sched->replay_repeat - 1) + sched->cpu_usage) / sched->replay_repeat;
sched->parent_cpu_usage = cpu_usage_1 - cpu_usage_0;
if (!sched->runavg_parent_cpu_usage)
sched->runavg_parent_cpu_usage = sched->parent_cpu_usage;
sched->runavg_parent_cpu_usage = (sched->runavg_parent_cpu_usage * (sched->replay_repeat - 1) +
sched->parent_cpu_usage)/sched->replay_repeat;
ret = pthread_mutex_lock(&sched->start_work_mutex);
BUG_ON(ret);
for (i = 0; i < sched->nr_tasks; i++) {
task = sched->tasks[i];
sem_init(&task->sleep_sem, 0, 0);
task->curr_event = 0;
}
}
static void run_one_test(struct perf_sched *sched)
{
u64 T0, T1, delta, avg_delta, fluct;
T0 = get_nsecs();
wait_for_tasks(sched);
T1 = get_nsecs();
delta = T1 - T0;
sched->sum_runtime += delta;
sched->nr_runs++;
avg_delta = sched->sum_runtime / sched->nr_runs;
if (delta < avg_delta)
fluct = avg_delta - delta;
else
fluct = delta - avg_delta;
sched->sum_fluct += fluct;
if (!sched->run_avg)
sched->run_avg = delta;
sched->run_avg = (sched->run_avg * (sched->replay_repeat - 1) + delta) / sched->replay_repeat;
printf("#%-3ld: %0.3f, ", sched->nr_runs, (double)delta / NSEC_PER_MSEC);
printf("ravg: %0.2f, ", (double)sched->run_avg / NSEC_PER_MSEC);
printf("cpu: %0.2f / %0.2f",
(double)sched->cpu_usage / NSEC_PER_MSEC, (double)sched->runavg_cpu_usage / NSEC_PER_MSEC);
#if 0
/*
* rusage statistics done by the parent, these are less
* accurate than the sched->sum_exec_runtime based statistics:
*/
printf(" [%0.2f / %0.2f]",
(double)sched->parent_cpu_usage / NSEC_PER_MSEC,
(double)sched->runavg_parent_cpu_usage / NSEC_PER_MSEC);
#endif
printf("\n");
if (sched->nr_sleep_corrections)
printf(" (%ld sleep corrections)\n", sched->nr_sleep_corrections);
sched->nr_sleep_corrections = 0;
}
static void test_calibrations(struct perf_sched *sched)
{
u64 T0, T1;
T0 = get_nsecs();
burn_nsecs(sched, NSEC_PER_MSEC);
T1 = get_nsecs();
printf("the run test took %" PRIu64 " nsecs\n", T1 - T0);
T0 = get_nsecs();
sleep_nsecs(NSEC_PER_MSEC);
T1 = get_nsecs();
printf("the sleep test took %" PRIu64 " nsecs\n", T1 - T0);
}
static int
replay_wakeup_event(struct perf_sched *sched,
struct perf_evsel *evsel, struct perf_sample *sample,
struct machine *machine __maybe_unused)
{
const char *comm = perf_evsel__strval(evsel, sample, "comm");
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
struct task_desc *waker, *wakee;
if (verbose > 0) {
printf("sched_wakeup event %p\n", evsel);
printf(" ... pid %d woke up %s/%d\n", sample->tid, comm, pid);
}
waker = register_pid(sched, sample->tid, "<unknown>");
wakee = register_pid(sched, pid, comm);
add_sched_event_wakeup(sched, waker, sample->time, wakee);
return 0;
}
static int replay_switch_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine __maybe_unused)
{
const char *prev_comm = perf_evsel__strval(evsel, sample, "prev_comm"),
*next_comm = perf_evsel__strval(evsel, sample, "next_comm");
const u32 prev_pid = perf_evsel__intval(evsel, sample, "prev_pid"),
next_pid = perf_evsel__intval(evsel, sample, "next_pid");
const u64 prev_state = perf_evsel__intval(evsel, sample, "prev_state");
struct task_desc *prev, __maybe_unused *next;
u64 timestamp0, timestamp = sample->time;
int cpu = sample->cpu;
s64 delta;
if (verbose > 0)
printf("sched_switch event %p\n", evsel);
if (cpu >= MAX_CPUS || cpu < 0)
return 0;
timestamp0 = sched->cpu_last_switched[cpu];
if (timestamp0)
delta = timestamp - timestamp0;
else
delta = 0;
if (delta < 0) {
pr_err("hm, delta: %" PRIu64 " < 0 ?\n", delta);
return -1;
}
pr_debug(" ... switch from %s/%d to %s/%d [ran %" PRIu64 " nsecs]\n",
prev_comm, prev_pid, next_comm, next_pid, delta);
prev = register_pid(sched, prev_pid, prev_comm);
next = register_pid(sched, next_pid, next_comm);
sched->cpu_last_switched[cpu] = timestamp;
add_sched_event_run(sched, prev, timestamp, delta);
add_sched_event_sleep(sched, prev, timestamp, prev_state);
return 0;
}
static int replay_fork_event(struct perf_sched *sched,
union perf_event *event,
struct machine *machine)
{
struct thread *child, *parent;
child = machine__findnew_thread(machine, event->fork.pid,
event->fork.tid);
parent = machine__findnew_thread(machine, event->fork.ppid,
event->fork.ptid);
if (child == NULL || parent == NULL) {
pr_debug("thread does not exist on fork event: child %p, parent %p\n",
child, parent);
goto out_put;
}
if (verbose > 0) {
printf("fork event\n");
printf("... parent: %s/%d\n", thread__comm_str(parent), parent->tid);
printf("... child: %s/%d\n", thread__comm_str(child), child->tid);
}
register_pid(sched, parent->tid, thread__comm_str(parent));
register_pid(sched, child->tid, thread__comm_str(child));
out_put:
thread__put(child);
thread__put(parent);
return 0;
}
struct sort_dimension {
const char *name;
sort_fn_t cmp;
struct list_head list;
};
static int
thread_lat_cmp(struct list_head *list, struct work_atoms *l, struct work_atoms *r)
{
struct sort_dimension *sort;
int ret = 0;
BUG_ON(list_empty(list));
list_for_each_entry(sort, list, list) {
ret = sort->cmp(l, r);
if (ret)
return ret;
}
return ret;
}
static struct work_atoms *
thread_atoms_search(struct rb_root *root, struct thread *thread,
struct list_head *sort_list)
{
struct rb_node *node = root->rb_node;
struct work_atoms key = { .thread = thread };
while (node) {
struct work_atoms *atoms;
int cmp;
atoms = container_of(node, struct work_atoms, node);
cmp = thread_lat_cmp(sort_list, &key, atoms);
if (cmp > 0)
node = node->rb_left;
else if (cmp < 0)
node = node->rb_right;
else {
BUG_ON(thread != atoms->thread);
return atoms;
}
}
return NULL;
}
static void
__thread_latency_insert(struct rb_root *root, struct work_atoms *data,
struct list_head *sort_list)
{
struct rb_node **new = &(root->rb_node), *parent = NULL;
while (*new) {
struct work_atoms *this;
int cmp;
this = container_of(*new, struct work_atoms, node);
parent = *new;
cmp = thread_lat_cmp(sort_list, data, this);
if (cmp > 0)
new = &((*new)->rb_left);
else
new = &((*new)->rb_right);
}
rb_link_node(&data->node, parent, new);
rb_insert_color(&data->node, root);
}
static int thread_atoms_insert(struct perf_sched *sched, struct thread *thread)
{
struct work_atoms *atoms = zalloc(sizeof(*atoms));
if (!atoms) {
pr_err("No memory at %s\n", __func__);
return -1;
}
atoms->thread = thread__get(thread);
INIT_LIST_HEAD(&atoms->work_list);
__thread_latency_insert(&sched->atom_root, atoms, &sched->cmp_pid);
return 0;
}
static char sched_out_state(u64 prev_state)
{
const char *str = TASK_STATE_TO_CHAR_STR;
return str[prev_state];
}
static int
add_sched_out_event(struct work_atoms *atoms,
char run_state,
u64 timestamp)
{
struct work_atom *atom = zalloc(sizeof(*atom));
if (!atom) {
pr_err("Non memory at %s", __func__);
return -1;
}
atom->sched_out_time = timestamp;
if (run_state == 'R') {
atom->state = THREAD_WAIT_CPU;
atom->wake_up_time = atom->sched_out_time;
}
list_add_tail(&atom->list, &atoms->work_list);
return 0;
}
static void
add_runtime_event(struct work_atoms *atoms, u64 delta,
u64 timestamp __maybe_unused)
{
struct work_atom *atom;
BUG_ON(list_empty(&atoms->work_list));
atom = list_entry(atoms->work_list.prev, struct work_atom, list);
atom->runtime += delta;
atoms->total_runtime += delta;
}
static void
add_sched_in_event(struct work_atoms *atoms, u64 timestamp)
{
struct work_atom *atom;
u64 delta;
if (list_empty(&atoms->work_list))
return;
atom = list_entry(atoms->work_list.prev, struct work_atom, list);
if (atom->state != THREAD_WAIT_CPU)
return;
if (timestamp < atom->wake_up_time) {
atom->state = THREAD_IGNORE;
return;
}
atom->state = THREAD_SCHED_IN;
atom->sched_in_time = timestamp;
delta = atom->sched_in_time - atom->wake_up_time;
atoms->total_lat += delta;
if (delta > atoms->max_lat) {
atoms->max_lat = delta;
atoms->max_lat_at = timestamp;
}
atoms->nb_atoms++;
}
static int latency_switch_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
const u32 prev_pid = perf_evsel__intval(evsel, sample, "prev_pid"),
next_pid = perf_evsel__intval(evsel, sample, "next_pid");
const u64 prev_state = perf_evsel__intval(evsel, sample, "prev_state");
struct work_atoms *out_events, *in_events;
struct thread *sched_out, *sched_in;
u64 timestamp0, timestamp = sample->time;
int cpu = sample->cpu, err = -1;
s64 delta;
BUG_ON(cpu >= MAX_CPUS || cpu < 0);
timestamp0 = sched->cpu_last_switched[cpu];
sched->cpu_last_switched[cpu] = timestamp;
if (timestamp0)
delta = timestamp - timestamp0;
else
delta = 0;
if (delta < 0) {
pr_err("hm, delta: %" PRIu64 " < 0 ?\n", delta);
return -1;
}
sched_out = machine__findnew_thread(machine, -1, prev_pid);
sched_in = machine__findnew_thread(machine, -1, next_pid);
if (sched_out == NULL || sched_in == NULL)
goto out_put;
out_events = thread_atoms_search(&sched->atom_root, sched_out, &sched->cmp_pid);
if (!out_events) {
if (thread_atoms_insert(sched, sched_out))
goto out_put;
out_events = thread_atoms_search(&sched->atom_root, sched_out, &sched->cmp_pid);
if (!out_events) {
pr_err("out-event: Internal tree error");
goto out_put;
}
}
if (add_sched_out_event(out_events, sched_out_state(prev_state), timestamp))
return -1;
in_events = thread_atoms_search(&sched->atom_root, sched_in, &sched->cmp_pid);
if (!in_events) {
if (thread_atoms_insert(sched, sched_in))
goto out_put;
in_events = thread_atoms_search(&sched->atom_root, sched_in, &sched->cmp_pid);
if (!in_events) {
pr_err("in-event: Internal tree error");
goto out_put;
}
/*
* Take came in we have not heard about yet,
* add in an initial atom in runnable state:
*/
if (add_sched_out_event(in_events, 'R', timestamp))
goto out_put;
}
add_sched_in_event(in_events, timestamp);
err = 0;
out_put:
thread__put(sched_out);
thread__put(sched_in);
return err;
}
static int latency_runtime_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
const u64 runtime = perf_evsel__intval(evsel, sample, "runtime");
struct thread *thread = machine__findnew_thread(machine, -1, pid);
struct work_atoms *atoms = thread_atoms_search(&sched->atom_root, thread, &sched->cmp_pid);
u64 timestamp = sample->time;
int cpu = sample->cpu, err = -1;
if (thread == NULL)
return -1;
BUG_ON(cpu >= MAX_CPUS || cpu < 0);
if (!atoms) {
if (thread_atoms_insert(sched, thread))
goto out_put;
atoms = thread_atoms_search(&sched->atom_root, thread, &sched->cmp_pid);
if (!atoms) {
pr_err("in-event: Internal tree error");
goto out_put;
}
if (add_sched_out_event(atoms, 'R', timestamp))
goto out_put;
}
add_runtime_event(atoms, runtime, timestamp);
err = 0;
out_put:
thread__put(thread);
return err;
}
static int latency_wakeup_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
struct work_atoms *atoms;
struct work_atom *atom;
struct thread *wakee;
u64 timestamp = sample->time;
int err = -1;
wakee = machine__findnew_thread(machine, -1, pid);
if (wakee == NULL)
return -1;
atoms = thread_atoms_search(&sched->atom_root, wakee, &sched->cmp_pid);
if (!atoms) {
if (thread_atoms_insert(sched, wakee))
goto out_put;
atoms = thread_atoms_search(&sched->atom_root, wakee, &sched->cmp_pid);
if (!atoms) {
pr_err("wakeup-event: Internal tree error");
goto out_put;
}
if (add_sched_out_event(atoms, 'S', timestamp))
goto out_put;
}
BUG_ON(list_empty(&atoms->work_list));
atom = list_entry(atoms->work_list.prev, struct work_atom, list);
/*
* As we do not guarantee the wakeup event happens when
* task is out of run queue, also may happen when task is
* on run queue and wakeup only change ->state to TASK_RUNNING,
* then we should not set the ->wake_up_time when wake up a
* task which is on run queue.
*
* You WILL be missing events if you've recorded only
* one CPU, or are only looking at only one, so don't
* skip in this case.
*/
if (sched->profile_cpu == -1 && atom->state != THREAD_SLEEPING)
goto out_ok;
sched->nr_timestamps++;
if (atom->sched_out_time > timestamp) {
sched->nr_unordered_timestamps++;
goto out_ok;
}
atom->state = THREAD_WAIT_CPU;
atom->wake_up_time = timestamp;
out_ok:
err = 0;
out_put:
thread__put(wakee);
return err;
}
static int latency_migrate_task_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
u64 timestamp = sample->time;
struct work_atoms *atoms;
struct work_atom *atom;
struct thread *migrant;
int err = -1;
/*
* Only need to worry about migration when profiling one CPU.
*/
if (sched->profile_cpu == -1)
return 0;
migrant = machine__findnew_thread(machine, -1, pid);
if (migrant == NULL)
return -1;
atoms = thread_atoms_search(&sched->atom_root, migrant, &sched->cmp_pid);
if (!atoms) {
if (thread_atoms_insert(sched, migrant))
goto out_put;
register_pid(sched, migrant->tid, thread__comm_str(migrant));
atoms = thread_atoms_search(&sched->atom_root, migrant, &sched->cmp_pid);
if (!atoms) {
pr_err("migration-event: Internal tree error");
goto out_put;
}
if (add_sched_out_event(atoms, 'R', timestamp))
goto out_put;
}
BUG_ON(list_empty(&atoms->work_list));
atom = list_entry(atoms->work_list.prev, struct work_atom, list);
atom->sched_in_time = atom->sched_out_time = atom->wake_up_time = timestamp;
sched->nr_timestamps++;
if (atom->sched_out_time > timestamp)
sched->nr_unordered_timestamps++;
err = 0;
out_put:
thread__put(migrant);
return err;
}
static void output_lat_thread(struct perf_sched *sched, struct work_atoms *work_list)
{
int i;
int ret;
u64 avg;
char max_lat_at[32];
if (!work_list->nb_atoms)
return;
/*
* Ignore idle threads:
*/
if (!strcmp(thread__comm_str(work_list->thread), "swapper"))
return;
sched->all_runtime += work_list->total_runtime;
sched->all_count += work_list->nb_atoms;
if (work_list->num_merged > 1)
ret = printf(" %s:(%d) ", thread__comm_str(work_list->thread), work_list->num_merged);
else
ret = printf(" %s:%d ", thread__comm_str(work_list->thread), work_list->thread->tid);
for (i = 0; i < 24 - ret; i++)
printf(" ");
avg = work_list->total_lat / work_list->nb_atoms;
timestamp__scnprintf_usec(work_list->max_lat_at, max_lat_at, sizeof(max_lat_at));
printf("|%11.3f ms |%9" PRIu64 " | avg:%9.3f ms | max:%9.3f ms | max at: %13s s\n",
(double)work_list->total_runtime / NSEC_PER_MSEC,
work_list->nb_atoms, (double)avg / NSEC_PER_MSEC,
(double)work_list->max_lat / NSEC_PER_MSEC,
max_lat_at);
}
static int pid_cmp(struct work_atoms *l, struct work_atoms *r)
{
if (l->thread == r->thread)
return 0;
if (l->thread->tid < r->thread->tid)
return -1;
if (l->thread->tid > r->thread->tid)
return 1;
return (int)(l->thread - r->thread);
}
static int avg_cmp(struct work_atoms *l, struct work_atoms *r)
{
u64 avgl, avgr;
if (!l->nb_atoms)
return -1;
if (!r->nb_atoms)
return 1;
avgl = l->total_lat / l->nb_atoms;
avgr = r->total_lat / r->nb_atoms;
if (avgl < avgr)
return -1;
if (avgl > avgr)
return 1;
return 0;
}
static int max_cmp(struct work_atoms *l, struct work_atoms *r)
{
if (l->max_lat < r->max_lat)
return -1;
if (l->max_lat > r->max_lat)
return 1;
return 0;
}
static int switch_cmp(struct work_atoms *l, struct work_atoms *r)
{
if (l->nb_atoms < r->nb_atoms)
return -1;
if (l->nb_atoms > r->nb_atoms)
return 1;
return 0;
}
static int runtime_cmp(struct work_atoms *l, struct work_atoms *r)
{
if (l->total_runtime < r->total_runtime)
return -1;
if (l->total_runtime > r->total_runtime)
return 1;
return 0;
}
static int sort_dimension__add(const char *tok, struct list_head *list)
{
size_t i;
static struct sort_dimension avg_sort_dimension = {
.name = "avg",
.cmp = avg_cmp,
};
static struct sort_dimension max_sort_dimension = {
.name = "max",
.cmp = max_cmp,
};
static struct sort_dimension pid_sort_dimension = {
.name = "pid",
.cmp = pid_cmp,
};
static struct sort_dimension runtime_sort_dimension = {
.name = "runtime",
.cmp = runtime_cmp,
};
static struct sort_dimension switch_sort_dimension = {
.name = "switch",
.cmp = switch_cmp,
};
struct sort_dimension *available_sorts[] = {
&pid_sort_dimension,
&avg_sort_dimension,
&max_sort_dimension,
&switch_sort_dimension,
&runtime_sort_dimension,
};
for (i = 0; i < ARRAY_SIZE(available_sorts); i++) {
if (!strcmp(available_sorts[i]->name, tok)) {
list_add_tail(&available_sorts[i]->list, list);
return 0;
}
}
return -1;
}
static void perf_sched__sort_lat(struct perf_sched *sched)
{
struct rb_node *node;
struct rb_root *root = &sched->atom_root;
again:
for (;;) {
struct work_atoms *data;
node = rb_first(root);
if (!node)
break;
rb_erase(node, root);
data = rb_entry(node, struct work_atoms, node);
__thread_latency_insert(&sched->sorted_atom_root, data, &sched->sort_list);
}
if (root == &sched->atom_root) {
root = &sched->merged_atom_root;
goto again;
}
}
static int process_sched_wakeup_event(struct perf_tool *tool,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
if (sched->tp_handler->wakeup_event)
return sched->tp_handler->wakeup_event(sched, evsel, sample, machine);
return 0;
}
union map_priv {
void *ptr;
bool color;
};
static bool thread__has_color(struct thread *thread)
{
union map_priv priv = {
.ptr = thread__priv(thread),
};
return priv.color;
}
static struct thread*
map__findnew_thread(struct perf_sched *sched, struct machine *machine, pid_t pid, pid_t tid)
{
struct thread *thread = machine__findnew_thread(machine, pid, tid);
union map_priv priv = {
.color = false,
};
if (!sched->map.color_pids || !thread || thread__priv(thread))
return thread;
if (thread_map__has(sched->map.color_pids, tid))
priv.color = true;
thread__set_priv(thread, priv.ptr);
return thread;
}
static int map_switch_event(struct perf_sched *sched, struct perf_evsel *evsel,
struct perf_sample *sample, struct machine *machine)
{
const u32 next_pid = perf_evsel__intval(evsel, sample, "next_pid");
struct thread *sched_in;
int new_shortname;
u64 timestamp0, timestamp = sample->time;
s64 delta;
int i, this_cpu = sample->cpu;
int cpus_nr;
bool new_cpu = false;
const char *color = PERF_COLOR_NORMAL;
char stimestamp[32];
BUG_ON(this_cpu >= MAX_CPUS || this_cpu < 0);
if (this_cpu > sched->max_cpu)
sched->max_cpu = this_cpu;
if (sched->map.comp) {
cpus_nr = bitmap_weight(sched->map.comp_cpus_mask, MAX_CPUS);
if (!test_and_set_bit(this_cpu, sched->map.comp_cpus_mask)) {
sched->map.comp_cpus[cpus_nr++] = this_cpu;
new_cpu = true;
}
} else
cpus_nr = sched->max_cpu;
timestamp0 = sched->cpu_last_switched[this_cpu];
sched->cpu_last_switched[this_cpu] = timestamp;
if (timestamp0)
delta = timestamp - timestamp0;
else
delta = 0;
if (delta < 0) {
pr_err("hm, delta: %" PRIu64 " < 0 ?\n", delta);
return -1;
}
sched_in = map__findnew_thread(sched, machine, -1, next_pid);
if (sched_in == NULL)
return -1;
sched->curr_thread[this_cpu] = thread__get(sched_in);
printf(" ");
new_shortname = 0;
if (!sched_in->shortname[0]) {
if (!strcmp(thread__comm_str(sched_in), "swapper")) {
/*
* Don't allocate a letter-number for swapper:0
* as a shortname. Instead, we use '.' for it.
*/
sched_in->shortname[0] = '.';
sched_in->shortname[1] = ' ';
} else {
sched_in->shortname[0] = sched->next_shortname1;
sched_in->shortname[1] = sched->next_shortname2;
if (sched->next_shortname1 < 'Z') {
sched->next_shortname1++;
} else {
sched->next_shortname1 = 'A';
if (sched->next_shortname2 < '9')
sched->next_shortname2++;
else
sched->next_shortname2 = '0';
}
}
new_shortname = 1;
}
for (i = 0; i < cpus_nr; i++) {
int cpu = sched->map.comp ? sched->map.comp_cpus[i] : i;
struct thread *curr_thread = sched->curr_thread[cpu];
const char *pid_color = color;
const char *cpu_color = color;
if (curr_thread && thread__has_color(curr_thread))
pid_color = COLOR_PIDS;
if (sched->map.cpus && !cpu_map__has(sched->map.cpus, cpu))
continue;
if (sched->map.color_cpus && cpu_map__has(sched->map.color_cpus, cpu))
cpu_color = COLOR_CPUS;
if (cpu != this_cpu)
color_fprintf(stdout, color, " ");
else
color_fprintf(stdout, cpu_color, "*");
if (sched->curr_thread[cpu])
color_fprintf(stdout, pid_color, "%2s ", sched->curr_thread[cpu]->shortname);
else
color_fprintf(stdout, color, " ");
}
if (sched->map.cpus && !cpu_map__has(sched->map.cpus, this_cpu))
goto out;
timestamp__scnprintf_usec(timestamp, stimestamp, sizeof(stimestamp));
color_fprintf(stdout, color, " %12s secs ", stimestamp);
if (new_shortname || (verbose > 0 && sched_in->tid)) {
const char *pid_color = color;
if (thread__has_color(sched_in))
pid_color = COLOR_PIDS;
color_fprintf(stdout, pid_color, "%s => %s:%d",
sched_in->shortname, thread__comm_str(sched_in), sched_in->tid);
}
if (sched->map.comp && new_cpu)
color_fprintf(stdout, color, " (CPU %d)", this_cpu);
out:
color_fprintf(stdout, color, "\n");
thread__put(sched_in);
return 0;
}
static int process_sched_switch_event(struct perf_tool *tool,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
int this_cpu = sample->cpu, err = 0;
u32 prev_pid = perf_evsel__intval(evsel, sample, "prev_pid"),
next_pid = perf_evsel__intval(evsel, sample, "next_pid");
if (sched->curr_pid[this_cpu] != (u32)-1) {
/*
* Are we trying to switch away a PID that is
* not current?
*/
if (sched->curr_pid[this_cpu] != prev_pid)
sched->nr_context_switch_bugs++;
}
if (sched->tp_handler->switch_event)
err = sched->tp_handler->switch_event(sched, evsel, sample, machine);
sched->curr_pid[this_cpu] = next_pid;
return err;
}
static int process_sched_runtime_event(struct perf_tool *tool,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
if (sched->tp_handler->runtime_event)
return sched->tp_handler->runtime_event(sched, evsel, sample, machine);
return 0;
}
static int perf_sched__process_fork_event(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
/* run the fork event through the perf machineruy */
perf_event__process_fork(tool, event, sample, machine);
/* and then run additional processing needed for this command */
if (sched->tp_handler->fork_event)
return sched->tp_handler->fork_event(sched, event, machine);
return 0;
}
static int process_sched_migrate_task_event(struct perf_tool *tool,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
if (sched->tp_handler->migrate_task_event)
return sched->tp_handler->migrate_task_event(sched, evsel, sample, machine);
return 0;
}
typedef int (*tracepoint_handler)(struct perf_tool *tool,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine);
static int perf_sched__process_tracepoint_sample(struct perf_tool *tool __maybe_unused,
union perf_event *event __maybe_unused,
struct perf_sample *sample,
struct perf_evsel *evsel,
struct machine *machine)
{
int err = 0;
if (evsel->handler != NULL) {
tracepoint_handler f = evsel->handler;
err = f(tool, evsel, sample, machine);
}
return err;
}
static int perf_sched__read_events(struct perf_sched *sched)
{
const struct perf_evsel_str_handler handlers[] = {
{ "sched:sched_switch", process_sched_switch_event, },
{ "sched:sched_stat_runtime", process_sched_runtime_event, },
{ "sched:sched_wakeup", process_sched_wakeup_event, },
{ "sched:sched_wakeup_new", process_sched_wakeup_event, },
{ "sched:sched_migrate_task", process_sched_migrate_task_event, },
};
struct perf_session *session;
struct perf_data_file file = {
.path = input_name,
.mode = PERF_DATA_MODE_READ,
.force = sched->force,
};
int rc = -1;
session = perf_session__new(&file, false, &sched->tool);
if (session == NULL) {
pr_debug("No Memory for session\n");
return -1;
}
symbol__init(&session->header.env);
if (perf_session__set_tracepoints_handlers(session, handlers))
goto out_delete;
if (perf_session__has_traces(session, "record -R")) {
int err = perf_session__process_events(session);
if (err) {
pr_err("Failed to process events, error %d", err);
goto out_delete;
}
sched->nr_events = session->evlist->stats.nr_events[0];
sched->nr_lost_events = session->evlist->stats.total_lost;
sched->nr_lost_chunks = session->evlist->stats.nr_events[PERF_RECORD_LOST];
}
rc = 0;
out_delete:
perf_session__delete(session);
return rc;
}
/*
* scheduling times are printed as msec.usec
*/
static inline void print_sched_time(unsigned long long nsecs, int width)
{
unsigned long msecs;
unsigned long usecs;
msecs = nsecs / NSEC_PER_MSEC;
nsecs -= msecs * NSEC_PER_MSEC;
usecs = nsecs / NSEC_PER_USEC;
printf("%*lu.%03lu ", width, msecs, usecs);
}
/*
* returns runtime data for event, allocating memory for it the
* first time it is used.
*/
static struct evsel_runtime *perf_evsel__get_runtime(struct perf_evsel *evsel)
{
struct evsel_runtime *r = evsel->priv;
if (r == NULL) {
r = zalloc(sizeof(struct evsel_runtime));
evsel->priv = r;
}
return r;
}
/*
* save last time event was seen per cpu
*/
static void perf_evsel__save_time(struct perf_evsel *evsel,
u64 timestamp, u32 cpu)
{
struct evsel_runtime *r = perf_evsel__get_runtime(evsel);
if (r == NULL)
return;
if ((cpu >= r->ncpu) || (r->last_time == NULL)) {
int i, n = __roundup_pow_of_two(cpu+1);
void *p = r->last_time;
p = realloc(r->last_time, n * sizeof(u64));
if (!p)
return;
r->last_time = p;
for (i = r->ncpu; i < n; ++i)
r->last_time[i] = (u64) 0;
r->ncpu = n;
}
r->last_time[cpu] = timestamp;
}
/* returns last time this event was seen on the given cpu */
static u64 perf_evsel__get_time(struct perf_evsel *evsel, u32 cpu)
{
struct evsel_runtime *r = perf_evsel__get_runtime(evsel);
if ((r == NULL) || (r->last_time == NULL) || (cpu >= r->ncpu))
return 0;
return r->last_time[cpu];
}
static int comm_width = 30;
static char *timehist_get_commstr(struct thread *thread)
{
static char str[32];
const char *comm = thread__comm_str(thread);
pid_t tid = thread->tid;
pid_t pid = thread->pid_;
int n;
if (pid == 0)
n = scnprintf(str, sizeof(str), "%s", comm);
else if (tid != pid)
n = scnprintf(str, sizeof(str), "%s[%d/%d]", comm, tid, pid);
else
n = scnprintf(str, sizeof(str), "%s[%d]", comm, tid);
if (n > comm_width)
comm_width = n;
return str;
}
static void timehist_header(struct perf_sched *sched)
{
u32 ncpus = sched->max_cpu + 1;
u32 i, j;
printf("%15s %6s ", "time", "cpu");
if (sched->show_cpu_visual) {
printf(" ");
for (i = 0, j = 0; i < ncpus; ++i) {
printf("%x", j++);
if (j > 15)
j = 0;
}
printf(" ");
}
printf(" %-*s %9s %9s %9s", comm_width,
"task name", "wait time", "sch delay", "run time");
if (sched->show_state)
printf(" %s", "state");
printf("\n");
/*
* units row
*/
printf("%15s %-6s ", "", "");
if (sched->show_cpu_visual)
printf(" %*s ", ncpus, "");
printf(" %-*s %9s %9s %9s", comm_width,
"[tid/pid]", "(msec)", "(msec)", "(msec)");
if (sched->show_state)
printf(" %5s", "");
printf("\n");
/*
* separator
*/
printf("%.15s %.6s ", graph_dotted_line, graph_dotted_line);
if (sched->show_cpu_visual)
printf(" %.*s ", ncpus, graph_dotted_line);
printf(" %.*s %.9s %.9s %.9s", comm_width,
graph_dotted_line, graph_dotted_line, graph_dotted_line,
graph_dotted_line);
if (sched->show_state)
printf(" %.5s", graph_dotted_line);
printf("\n");
}
static char task_state_char(struct thread *thread, int state)
{
static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
unsigned bit = state ? ffs(state) : 0;
/* 'I' for idle */
if (thread->tid == 0)
return 'I';
return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
}
static void timehist_print_sample(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct addr_location *al,
struct thread *thread,
u64 t, int state)
{
struct thread_runtime *tr = thread__priv(thread);
const char *next_comm = perf_evsel__strval(evsel, sample, "next_comm");
const u32 next_pid = perf_evsel__intval(evsel, sample, "next_pid");
u32 max_cpus = sched->max_cpu + 1;
char tstr[64];
char nstr[30];
u64 wait_time;
timestamp__scnprintf_usec(t, tstr, sizeof(tstr));
printf("%15s [%04d] ", tstr, sample->cpu);
if (sched->show_cpu_visual) {
u32 i;
char c;
printf(" ");
for (i = 0; i < max_cpus; ++i) {
/* flag idle times with 'i'; others are sched events */
if (i == sample->cpu)
c = (thread->tid == 0) ? 'i' : 's';
else
c = ' ';
printf("%c", c);
}
printf(" ");
}
printf(" %-*s ", comm_width, timehist_get_commstr(thread));
wait_time = tr->dt_sleep + tr->dt_iowait + tr->dt_preempt;
print_sched_time(wait_time, 6);
print_sched_time(tr->dt_delay, 6);
print_sched_time(tr->dt_run, 6);
if (sched->show_state)
printf(" %5c ", task_state_char(thread, state));
if (sched->show_next) {
snprintf(nstr, sizeof(nstr), "next: %s[%d]", next_comm, next_pid);
printf(" %-*s", comm_width, nstr);
}
if (sched->show_wakeups && !sched->show_next)
printf(" %-*s", comm_width, "");
if (thread->tid == 0)
goto out;
if (sched->show_callchain)
printf(" ");
sample__fprintf_sym(sample, al, 0,
EVSEL__PRINT_SYM | EVSEL__PRINT_ONELINE |
EVSEL__PRINT_CALLCHAIN_ARROW |
EVSEL__PRINT_SKIP_IGNORED,
&callchain_cursor, stdout);
out:
printf("\n");
}
/*
* Explanation of delta-time stats:
*
* t = time of current schedule out event
* tprev = time of previous sched out event
* also time of schedule-in event for current task
* last_time = time of last sched change event for current task
* (i.e, time process was last scheduled out)
* ready_to_run = time of wakeup for current task
*
* -----|------------|------------|------------|------
* last ready tprev t
* time to run
*
* |-------- dt_wait --------|
* |- dt_delay -|-- dt_run --|
*
* dt_run = run time of current task
* dt_wait = time between last schedule out event for task and tprev
* represents time spent off the cpu
* dt_delay = time between wakeup and schedule-in of task
*/
static void timehist_update_runtime_stats(struct thread_runtime *r,
u64 t, u64 tprev)
{
r->dt_delay = 0;
r->dt_sleep = 0;
r->dt_iowait = 0;
r->dt_preempt = 0;
r->dt_run = 0;
if (tprev) {
r->dt_run = t - tprev;
if (r->ready_to_run) {
if (r->ready_to_run > tprev)
pr_debug("time travel: wakeup time for task > previous sched_switch event\n");
else
r->dt_delay = tprev - r->ready_to_run;
}
if (r->last_time > tprev)
pr_debug("time travel: last sched out time for task > previous sched_switch event\n");
else if (r->last_time) {
u64 dt_wait = tprev - r->last_time;
if (r->last_state == TASK_RUNNING)
r->dt_preempt = dt_wait;
else if (r->last_state == TASK_UNINTERRUPTIBLE)
r->dt_iowait = dt_wait;
else
r->dt_sleep = dt_wait;
}
}
update_stats(&r->run_stats, r->dt_run);
r->total_run_time += r->dt_run;
r->total_delay_time += r->dt_delay;
r->total_sleep_time += r->dt_sleep;
r->total_iowait_time += r->dt_iowait;
r->total_preempt_time += r->dt_preempt;
}
static bool is_idle_sample(struct perf_sample *sample,
struct perf_evsel *evsel)
{
/* pid 0 == swapper == idle task */
if (strcmp(perf_evsel__name(evsel), "sched:sched_switch") == 0)
return perf_evsel__intval(evsel, sample, "prev_pid") == 0;
return sample->pid == 0;
}
static void save_task_callchain(struct perf_sched *sched,
struct perf_sample *sample,
struct perf_evsel *evsel,
struct machine *machine)
{
struct callchain_cursor *cursor = &callchain_cursor;
struct thread *thread;
/* want main thread for process - has maps */
thread = machine__findnew_thread(machine, sample->pid, sample->pid);
if (thread == NULL) {
pr_debug("Failed to get thread for pid %d.\n", sample->pid);
return;
}
if (!symbol_conf.use_callchain || sample->callchain == NULL)
return;
if (thread__resolve_callchain(thread, cursor, evsel, sample,
NULL, NULL, sched->max_stack + 2) != 0) {
if (verbose > 0)
pr_err("Failed to resolve callchain. Skipping\n");
return;
}
callchain_cursor_commit(cursor);
while (true) {
struct callchain_cursor_node *node;
struct symbol *sym;
node = callchain_cursor_current(cursor);
if (node == NULL)
break;
sym = node->sym;
if (sym) {
if (!strcmp(sym->name, "schedule") ||
!strcmp(sym->name, "__schedule") ||
!strcmp(sym->name, "preempt_schedule"))
sym->ignore = 1;
}
callchain_cursor_advance(cursor);
}
}
static int init_idle_thread(struct thread *thread)
{
struct idle_thread_runtime *itr;
thread__set_comm(thread, idle_comm, 0);
itr = zalloc(sizeof(*itr));
if (itr == NULL)
return -ENOMEM;
init_stats(&itr->tr.run_stats);
callchain_init(&itr->callchain);
callchain_cursor_reset(&itr->cursor);
thread__set_priv(thread, itr);
return 0;
}
/*
* Track idle stats per cpu by maintaining a local thread
* struct for the idle task on each cpu.
*/
static int init_idle_threads(int ncpu)
{
int i, ret;
idle_threads = zalloc(ncpu * sizeof(struct thread *));
if (!idle_threads)
return -ENOMEM;
idle_max_cpu = ncpu;
/* allocate the actual thread struct if needed */
for (i = 0; i < ncpu; ++i) {
idle_threads[i] = thread__new(0, 0);
if (idle_threads[i] == NULL)
return -ENOMEM;
ret = init_idle_thread(idle_threads[i]);
if (ret < 0)
return ret;
}
return 0;
}
static void free_idle_threads(void)
{
int i;
if (idle_threads == NULL)
return;
for (i = 0; i < idle_max_cpu; ++i) {
if ((idle_threads[i]))
thread__delete(idle_threads[i]);
}
free(idle_threads);
}
static struct thread *get_idle_thread(int cpu)
{
/*
* expand/allocate array of pointers to local thread
* structs if needed
*/
if ((cpu >= idle_max_cpu) || (idle_threads == NULL)) {
int i, j = __roundup_pow_of_two(cpu+1);
void *p;
p = realloc(idle_threads, j * sizeof(struct thread *));
if (!p)
return NULL;
idle_threads = (struct thread **) p;
for (i = idle_max_cpu; i < j; ++i)
idle_threads[i] = NULL;
idle_max_cpu = j;
}
/* allocate a new thread struct if needed */
if (idle_threads[cpu] == NULL) {
idle_threads[cpu] = thread__new(0, 0);
if (idle_threads[cpu]) {
if (init_idle_thread(idle_threads[cpu]) < 0)
return NULL;
}
}
return idle_threads[cpu];
}
static void save_idle_callchain(struct idle_thread_runtime *itr,
struct perf_sample *sample)
{
if (!symbol_conf.use_callchain || sample->callchain == NULL)
return;
callchain_cursor__copy(&itr->cursor, &callchain_cursor);
}
/*
* handle runtime stats saved per thread
*/
static struct thread_runtime *thread__init_runtime(struct thread *thread)
{
struct thread_runtime *r;
r = zalloc(sizeof(struct thread_runtime));
if (!r)
return NULL;
init_stats(&r->run_stats);
thread__set_priv(thread, r);
return r;
}
static struct thread_runtime *thread__get_runtime(struct thread *thread)
{
struct thread_runtime *tr;
tr = thread__priv(thread);
if (tr == NULL) {
tr = thread__init_runtime(thread);
if (tr == NULL)
pr_debug("Failed to malloc memory for runtime data.\n");
}
return tr;
}
static struct thread *timehist_get_thread(struct perf_sched *sched,
struct perf_sample *sample,
struct machine *machine,
struct perf_evsel *evsel)
{
struct thread *thread;
if (is_idle_sample(sample, evsel)) {
thread = get_idle_thread(sample->cpu);
if (thread == NULL)
pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);
} else {
/* there were samples with tid 0 but non-zero pid */
thread = machine__findnew_thread(machine, sample->pid,
sample->tid ?: sample->pid);
if (thread == NULL) {
pr_debug("Failed to get thread for tid %d. skipping sample.\n",
sample->tid);
}
save_task_callchain(sched, sample, evsel, machine);
if (sched->idle_hist) {
struct thread *idle;
struct idle_thread_runtime *itr;
idle = get_idle_thread(sample->cpu);
if (idle == NULL) {
pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);
return NULL;
}
itr = thread__priv(idle);
if (itr == NULL)
return NULL;
itr->last_thread = thread;
/* copy task callchain when entering to idle */
if (perf_evsel__intval(evsel, sample, "next_pid") == 0)
save_idle_callchain(itr, sample);
}
}
return thread;
}
static bool timehist_skip_sample(struct perf_sched *sched,
struct thread *thread,
struct perf_evsel *evsel,
struct perf_sample *sample)
{
bool rc = false;
if (thread__is_filtered(thread)) {
rc = true;
sched->skipped_samples++;
}
if (sched->idle_hist) {
if (strcmp(perf_evsel__name(evsel), "sched:sched_switch"))
rc = true;
else if (perf_evsel__intval(evsel, sample, "prev_pid") != 0 &&
perf_evsel__intval(evsel, sample, "next_pid") != 0)
rc = true;
}
return rc;
}
static void timehist_print_wakeup_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine,
struct thread *awakened)
{
struct thread *thread;
char tstr[64];
thread = machine__findnew_thread(machine, sample->pid, sample->tid);
if (thread == NULL)
return;
/* show wakeup unless both awakee and awaker are filtered */
if (timehist_skip_sample(sched, thread, evsel, sample) &&
timehist_skip_sample(sched, awakened, evsel, sample)) {
return;
}
timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
printf("%15s [%04d] ", tstr, sample->cpu);
if (sched->show_cpu_visual)
printf(" %*s ", sched->max_cpu + 1, "");
printf(" %-*s ", comm_width, timehist_get_commstr(thread));
/* dt spacer */
printf(" %9s %9s %9s ", "", "", "");
printf("awakened: %s", timehist_get_commstr(awakened));
printf("\n");
}
static int timehist_sched_wakeup_event(struct perf_tool *tool,
union perf_event *event __maybe_unused,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
struct thread *thread;
struct thread_runtime *tr = NULL;
/* want pid of awakened task not pid in sample */
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
thread = machine__findnew_thread(machine, 0, pid);
if (thread == NULL)
return -1;
tr = thread__get_runtime(thread);
if (tr == NULL)
return -1;
if (tr->ready_to_run == 0)
tr->ready_to_run = sample->time;
/* show wakeups if requested */
if (sched->show_wakeups &&
!perf_time__skip_sample(&sched->ptime, sample->time))
timehist_print_wakeup_event(sched, evsel, sample, machine, thread);
return 0;
}
static void timehist_print_migration_event(struct perf_sched *sched,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine,
struct thread *migrated)
{
struct thread *thread;
char tstr[64];
u32 max_cpus = sched->max_cpu + 1;
u32 ocpu, dcpu;
if (sched->summary_only)
return;
max_cpus = sched->max_cpu + 1;
ocpu = perf_evsel__intval(evsel, sample, "orig_cpu");
dcpu = perf_evsel__intval(evsel, sample, "dest_cpu");
thread = machine__findnew_thread(machine, sample->pid, sample->tid);
if (thread == NULL)
return;
if (timehist_skip_sample(sched, thread, evsel, sample) &&
timehist_skip_sample(sched, migrated, evsel, sample)) {
return;
}
timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
printf("%15s [%04d] ", tstr, sample->cpu);
if (sched->show_cpu_visual) {
u32 i;
char c;
printf(" ");
for (i = 0; i < max_cpus; ++i) {
c = (i == sample->cpu) ? 'm' : ' ';
printf("%c", c);
}
printf(" ");
}
printf(" %-*s ", comm_width, timehist_get_commstr(thread));
/* dt spacer */
printf(" %9s %9s %9s ", "", "", "");
printf("migrated: %s", timehist_get_commstr(migrated));
printf(" cpu %d => %d", ocpu, dcpu);
printf("\n");
}
static int timehist_migrate_task_event(struct perf_tool *tool,
union perf_event *event __maybe_unused,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
struct thread *thread;
struct thread_runtime *tr = NULL;
/* want pid of migrated task not pid in sample */
const u32 pid = perf_evsel__intval(evsel, sample, "pid");
thread = machine__findnew_thread(machine, 0, pid);
if (thread == NULL)
return -1;
tr = thread__get_runtime(thread);
if (tr == NULL)
return -1;
tr->migrations++;
/* show migrations if requested */
timehist_print_migration_event(sched, evsel, sample, machine, thread);
return 0;
}
static int timehist_sched_change_event(struct perf_tool *tool,
union perf_event *event,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine)
{
struct perf_sched *sched = container_of(tool, struct perf_sched, tool);
struct perf_time_interval *ptime = &sched->ptime;
struct addr_location al;
struct thread *thread;
struct thread_runtime *tr = NULL;
u64 tprev, t = sample->time;
int rc = 0;
int state = perf_evsel__intval(evsel, sample, "prev_state");
if (machine__resolve(machine, &al, sample) < 0) {
pr_err("problem processing %d event. skipping it\n",
event->header.type);
rc = -1;
goto out;
}
thread = timehist_get_thread(sched, sample, machine, evsel);
if (thread == NULL) {
rc = -1;
goto out;
}
if (timehist_skip_sample(sched, thread, evsel, sample))
goto out;
tr = thread__get_runtime(thread);
if (tr == NULL) {
rc = -1;
goto out;
}
tprev = perf_evsel__get_time(evsel, sample->cpu);
/*
* If start time given:
* - sample time is under window user cares about - skip sample
* - tprev is under window user cares about - reset to start of window
*/
if (ptime->start && ptime->start > t)
goto out;
if (tprev && ptime->start > tprev)
tprev = ptime->start;
/*
* If end time given:
* - previous sched event is out of window - we are done
* - sample time is beyond window user cares about - reset it
* to close out stats for time window interest
*/
if (ptime->end) {
if (tprev > ptime->end)
goto out;
if (t > ptime->end)
t = ptime->end;
}
if (!sched->idle_hist || thread->tid == 0) {
timehist_update_runtime_stats(tr, t, tprev);
if (sched->idle_hist) {
struct idle_thread_runtime *itr = (void *)tr;
struct thread_runtime *last_tr;
BUG_ON(thread->tid != 0);
if (itr->last_thread == NULL)
goto out;
/* add current idle time as last thread's runtime */
last_tr = thread__get_runtime(itr->last_thread);
if (last_tr == NULL)
goto out;
timehist_update_runtime_stats(last_tr, t, tprev);
/*
* remove delta time of last thread as it's not updated
* and otherwise it will show an invalid value next
* time. we only care total run time and run stat.
*/
last_tr->dt_run = 0;
last_tr->dt_delay = 0;
last_tr->dt_sleep = 0;
last_tr->dt_iowait = 0;
last_tr->dt_preempt = 0;
if (itr->cursor.nr)
callchain_append(&itr->callchain, &itr->cursor, t - tprev);
itr->last_thread = NULL;
}
}
if (!sched->summary_only)
timehist_print_sample(sched, evsel, sample, &al, thread, t, state);
out:
if (sched->hist_time.start == 0 && t >= ptime->start)
sched->hist_time.start = t;
if (ptime->end == 0 || t <= ptime->end)
sched->hist_time.end = t;
if (tr) {
/* time of this sched_switch event becomes last time task seen */
tr->last_time = sample->time;
/* last state is used to determine where to account wait time */
tr->last_state = state;
/* sched out event for task so reset ready to run time */
tr->ready_to_run = 0;
}
perf_evsel__save_time(evsel, sample->time, sample->cpu);
return rc;
}
static int timehist_sched_switch_event(struct perf_tool *tool,
union perf_event *event,
struct perf_evsel *evsel,
struct perf_sample *sample,
struct machine *machine __maybe_unused)
{
return timehist_sched_change_event(tool, event, evsel, sample, machine);
}
static int process_lost(struct perf_tool *tool __maybe_unused,
union perf_event *event,
struct perf_sample *sample,
struct machine *machine __maybe_unused)
{
char tstr[64];
timestamp__scnprintf_usec(sample->time, tstr, sizeof(tstr));
printf("%15s ", tstr);
printf("lost %" PRIu64 " events on cpu %d\n", event->lost.lost, sample->cpu);
return 0;
}
static void print_thread_runtime(struct thread *t,
struct thread_runtime *r)
{
double mean = avg_stats(&r->run_stats);
float stddev;
printf("%*s %5d %9" PRIu64 " ",
comm_width, timehist_get_commstr(t), t->ppid,
(u64) r->run_stats.n);
print_sched_time(r->total_run_time, 8);
stddev = rel_stddev_stats(stddev_stats(&r->run_stats), mean);
print_sched_time(r->run_stats.min, 6);
printf(" ");
print_sched_time((u64) mean, 6);
printf(" ");
print_sched_time(r->run_stats.max, 6);
printf(" ");
printf("%5.2f", stddev);
printf(" %5" PRIu64, r->migrations);
printf("\n");
}
static void print_thread_waittime(struct thread *t,
struct thread_runtime *r)
{
printf("%*s %5d %9" PRIu64 " ",
comm_width, timehist_get_commstr(t), t->ppid,
(u64) r->run_stats.n);
print_sched_time(r->total_run_time, 8);
print_sched_time(r->total_sleep_time, 6);
printf(" ");
print_sched_time(r->total_iowait_time, 6);
printf(" ");
print_sched_time(r->total_preempt_time, 6);
printf(" ");
print_sched_time(r->total_delay_time, 6);
printf("\n");
}
struct total_run_stats {
struct perf_sched *sched;
u64 sched_count;
u64 task_count;
u64 total_run_time;
};
static int __show_thread_runtime(struct thread *t, void *priv)
{
struct total_run_stats *stats = priv;
struct thread_runtime *r;
if (thread__is_filtered(t))
return 0;
r = thread__priv(t);
if (r && r->run_stats.n) {
stats->task_count++;
stats->sched_count += r->run_stats.n;
stats->total_run_time += r->total_run_time;
if (stats->sched->show_state)
print_thread_waittime(t, r);
else
print_thread_runtime(t, r);
}
return 0;
}
static int show_thread_runtime(struct thread *t, void *priv)
{
if (t->dead)
return 0;
return __show_thread_runtime(t, priv);
}
static int show_deadthread_runtime(struct thread *t, void *priv)
{
if (!t->dead)
return 0;
return __show_thread_runtime(t, priv);
}
static size_t callchain__fprintf_folded(FILE *fp, struct callchain_node *node)
{
const char *sep = " <- ";
struct callchain_list *chain;
size_t ret = 0;
char bf[1024];
bool first;
if (node == NULL)
return 0;
ret = callchain__fprintf_folded(fp, node->parent);
first = (ret == 0);
list_for_each_entry(chain, &node->val, list) {
if (chain->ip >= PERF_CONTEXT_MAX)
continue;
if (chain->ms.sym && chain->ms.sym->ignore)
continue;
ret += fprintf(fp, "%s%s", first ? "" : sep,
callchain_list__sym_name(chain, bf, sizeof(bf),
false));
first = false;
}
return ret;
}
static size_t timehist_print_idlehist_callchain(struct rb_root *root)
{
size_t ret = 0;
FILE *fp = stdout;
struct callchain_node *chain;
struct rb_node *rb_node = rb_first(root);
printf(" %16s %8s %s\n", "Idle time (msec)", "Count", "Callchains");
printf(