| /** |
| * Copyright (C) ARM Limited 2010-2014. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| |
| #include "gator.h" |
| #include <trace/events/irq.h> |
| |
| #define HARDIRQ 0 |
| #define SOFTIRQ 1 |
| #define TOTALIRQ (SOFTIRQ+1) |
| |
| static ulong hardirq_enabled; |
| static ulong softirq_enabled; |
| static ulong hardirq_key; |
| static ulong softirq_key; |
| static DEFINE_PER_CPU(atomic_t[TOTALIRQ], irqCnt); |
| static DEFINE_PER_CPU(int[TOTALIRQ * 2], irqGet); |
| |
| GATOR_DEFINE_PROBE(irq_handler_exit, |
| TP_PROTO(int irq, struct irqaction *action, int ret)) |
| { |
| atomic_inc(&per_cpu(irqCnt, get_physical_cpu())[HARDIRQ]); |
| } |
| |
| #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 37) |
| GATOR_DEFINE_PROBE(softirq_exit, TP_PROTO(struct softirq_action *h, struct softirq_action *vec)) |
| #else |
| GATOR_DEFINE_PROBE(softirq_exit, TP_PROTO(unsigned int vec_nr)) |
| #endif |
| { |
| atomic_inc(&per_cpu(irqCnt, get_physical_cpu())[SOFTIRQ]); |
| } |
| |
| static int gator_events_irq_create_files(struct super_block *sb, struct dentry *root) |
| { |
| struct dentry *dir; |
| |
| /* irq */ |
| dir = gatorfs_mkdir(sb, root, "Linux_irq_irq"); |
| if (!dir) { |
| return -1; |
| } |
| gatorfs_create_ulong(sb, dir, "enabled", &hardirq_enabled); |
| gatorfs_create_ro_ulong(sb, dir, "key", &hardirq_key); |
| |
| /* soft irq */ |
| dir = gatorfs_mkdir(sb, root, "Linux_irq_softirq"); |
| if (!dir) { |
| return -1; |
| } |
| gatorfs_create_ulong(sb, dir, "enabled", &softirq_enabled); |
| gatorfs_create_ro_ulong(sb, dir, "key", &softirq_key); |
| |
| return 0; |
| } |
| |
| static int gator_events_irq_online(int **buffer, bool migrate) |
| { |
| int len = 0, cpu = get_physical_cpu(); |
| |
| // synchronization with the irq_exit functions is not necessary as the values are being reset |
| if (hardirq_enabled) { |
| atomic_set(&per_cpu(irqCnt, cpu)[HARDIRQ], 0); |
| per_cpu(irqGet, cpu)[len++] = hardirq_key; |
| per_cpu(irqGet, cpu)[len++] = 0; |
| } |
| |
| if (softirq_enabled) { |
| atomic_set(&per_cpu(irqCnt, cpu)[SOFTIRQ], 0); |
| per_cpu(irqGet, cpu)[len++] = softirq_key; |
| per_cpu(irqGet, cpu)[len++] = 0; |
| } |
| |
| if (buffer) |
| *buffer = per_cpu(irqGet, cpu); |
| |
| return len; |
| } |
| |
| static int gator_events_irq_start(void) |
| { |
| // register tracepoints |
| if (hardirq_enabled) |
| if (GATOR_REGISTER_TRACE(irq_handler_exit)) |
| goto fail_hardirq_exit; |
| if (softirq_enabled) |
| if (GATOR_REGISTER_TRACE(softirq_exit)) |
| goto fail_softirq_exit; |
| pr_debug("gator: registered irq tracepoints\n"); |
| |
| return 0; |
| |
| // unregister tracepoints on error |
| fail_softirq_exit: |
| if (hardirq_enabled) |
| GATOR_UNREGISTER_TRACE(irq_handler_exit); |
| fail_hardirq_exit: |
| pr_err("gator: irq tracepoints failed to activate, please verify that tracepoints are enabled in the linux kernel\n"); |
| |
| return -1; |
| } |
| |
| static void gator_events_irq_stop(void) |
| { |
| if (hardirq_enabled) |
| GATOR_UNREGISTER_TRACE(irq_handler_exit); |
| if (softirq_enabled) |
| GATOR_UNREGISTER_TRACE(softirq_exit); |
| pr_debug("gator: unregistered irq tracepoints\n"); |
| |
| hardirq_enabled = 0; |
| softirq_enabled = 0; |
| } |
| |
| static int gator_events_irq_read(int **buffer) |
| { |
| int len, value; |
| int cpu = get_physical_cpu(); |
| |
| len = 0; |
| if (hardirq_enabled) { |
| value = atomic_read(&per_cpu(irqCnt, cpu)[HARDIRQ]); |
| atomic_sub(value, &per_cpu(irqCnt, cpu)[HARDIRQ]); |
| |
| per_cpu(irqGet, cpu)[len++] = hardirq_key; |
| per_cpu(irqGet, cpu)[len++] = value; |
| } |
| |
| if (softirq_enabled) { |
| value = atomic_read(&per_cpu(irqCnt, cpu)[SOFTIRQ]); |
| atomic_sub(value, &per_cpu(irqCnt, cpu)[SOFTIRQ]); |
| |
| per_cpu(irqGet, cpu)[len++] = softirq_key; |
| per_cpu(irqGet, cpu)[len++] = value; |
| } |
| |
| if (buffer) |
| *buffer = per_cpu(irqGet, cpu); |
| |
| return len; |
| } |
| |
| static struct gator_interface gator_events_irq_interface = { |
| .create_files = gator_events_irq_create_files, |
| .online = gator_events_irq_online, |
| .start = gator_events_irq_start, |
| .stop = gator_events_irq_stop, |
| .read = gator_events_irq_read, |
| }; |
| |
| int gator_events_irq_init(void) |
| { |
| hardirq_key = gator_events_get_key(); |
| softirq_key = gator_events_get_key(); |
| |
| hardirq_enabled = 0; |
| softirq_enabled = 0; |
| |
| return gator_events_install(&gator_events_irq_interface); |
| } |