[net-next-2.6.git] / drivers / oprofile / timer_int.c

/**
 * @file timer_int.c
 *
 * @remark Copyright 2002 OProfile authors
 * @remark Read the file COPYING
 *
 * @author John Levon <levon@movementarian.org>
 */

#include <linux/kernel.h>
#include <linux/notifier.h>
#include <linux/smp.h>
#include <linux/oprofile.h>
#include <linux/profile.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/hrtimer.h>
#include <asm/irq_regs.h>
#include <asm/ptrace.h>

#include "oprof.h"

static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
static int ctr_running;

static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
{
	oprofile_add_sample(get_irq_regs(), 0);
	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
	return HRTIMER_RESTART;
}

static void __oprofile_hrtimer_start(void *unused)
{
	struct hrtimer *hrtimer = &__get_cpu_var(oprofile_hrtimer);

	if (!ctr_running)
		return;

	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	hrtimer->function = oprofile_hrtimer_notify;

	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
		      HRTIMER_MODE_REL_PINNED);
}

static int oprofile_hrtimer_start(void)
{
	get_online_cpus();
	ctr_running = 1;
	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
	put_online_cpus();
	return 0;
}

static void __oprofile_hrtimer_stop(int cpu)
{
	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);

	if (!ctr_running)
		return;

	hrtimer_cancel(hrtimer);
}

static void oprofile_hrtimer_stop(void)
{
	int cpu;

	get_online_cpus();
	for_each_online_cpu(cpu)
		__oprofile_hrtimer_stop(cpu);
	ctr_running = 0;
	put_online_cpus();
}

static int __cpuinit oprofile_cpu_notify(struct notifier_block *self,
					 unsigned long action, void *hcpu)
{
	long cpu = (long) hcpu;

	switch (action) {
	case CPU_ONLINE:
	case CPU_ONLINE_FROZEN:
		smp_call_function_single(cpu, __oprofile_hrtimer_start,
					 NULL, 1);
		break;
	case CPU_DEAD:
	case CPU_DEAD_FROZEN:
		__oprofile_hrtimer_stop(cpu);
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block __refdata oprofile_cpu_notifier = {
	.notifier_call = oprofile_cpu_notify,
};

int __init oprofile_timer_init(struct oprofile_operations *ops)
{
	int rc;

	rc = register_hotcpu_notifier(&oprofile_cpu_notifier);
	if (rc)
		return rc;
	ops->create_files = NULL;
	ops->setup = NULL;
	ops->shutdown = NULL;
	ops->start = oprofile_hrtimer_start;
	ops->stop = oprofile_hrtimer_stop;
	ops->cpu_type = "timer";
	return 0;
}

void __exit oprofile_timer_exit(void)
{
	unregister_hotcpu_notifier(&oprofile_cpu_notifier);
}
Commit	Line	Data
1da177e4 LT	1	/**
	2	* @file timer_int.c
	3	*
	4	* @remark Copyright 2002 OProfile authors
	5	* @remark Read the file COPYING
	6	*
	7	* @author John Levon <levon@movementarian.org>
	8	*/
	9
	10	#include <linux/kernel.h>
	11	#include <linux/notifier.h>
	12	#include <linux/smp.h>
	13	#include <linux/oprofile.h>
	14	#include <linux/profile.h>
	15	#include <linux/init.h>
bc078e4e MS	16	#include <linux/cpu.h>
	17	#include <linux/hrtimer.h>
	18	#include <asm/irq_regs.h>
1da177e4 LT	19	#include <asm/ptrace.h>
	20
	21	#include "oprof.h"
	22
bc078e4e	23	static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
4ac3dbec	24	static int ctr_running;
bc078e4e MS	25
	26	static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
	27	{
	28	oprofile_add_sample(get_irq_regs(), 0);
	29	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
	30	return HRTIMER_RESTART;
	31	}
	32
	33	static void __oprofile_hrtimer_start(void *unused)
	34	{
	35	struct hrtimer *hrtimer = &__get_cpu_var(oprofile_hrtimer);
	36
4ac3dbec SS	37	if (!ctr_running)
	38	return;
	39
bc078e4e MS	40	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
	41	hrtimer->function = oprofile_hrtimer_notify;
	42
	43	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
	44	HRTIMER_MODE_REL_PINNED);
	45	}
	46
	47	static int oprofile_hrtimer_start(void)
1da177e4	48	{
4ac3dbec SS	49	get_online_cpus();
4ac3dbec SS	50	ctr_running = 1;
bc078e4e	51	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
4ac3dbec	52	put_online_cpus();
1da177e4 LT	53	return 0;
	54	}
	55
bc078e4e	56	static void __oprofile_hrtimer_stop(int cpu)
1da177e4	57	{
bc078e4e MS	58	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
bc078e4e MS	59
4ac3dbec SS	60	if (!ctr_running)
	61	return;
	62
bc078e4e	63	hrtimer_cancel(hrtimer);
1da177e4 LT	64	}
1da177e4 LT	65
bc078e4e MS	66	static void oprofile_hrtimer_stop(void)
	67	{
	68	int cpu;
	69
4ac3dbec	70	get_online_cpus();
bc078e4e MS	71	for_each_online_cpu(cpu)
bc078e4e MS	72	__oprofile_hrtimer_stop(cpu);
4ac3dbec SS	73	ctr_running = 0;
4ac3dbec SS	74	put_online_cpus();
bc078e4e	75	}
1da177e4	76
bc078e4e MS	77	static int __cpuinit oprofile_cpu_notify(struct notifier_block *self,
bc078e4e MS	78	unsigned long action, void *hcpu)
1da177e4	79	{
bc078e4e MS	80	long cpu = (long) hcpu;
	81
	82	switch (action) {
	83	case CPU_ONLINE:
	84	case CPU_ONLINE_FROZEN:
	85	smp_call_function_single(cpu, __oprofile_hrtimer_start,
	86	NULL, 1);
	87	break;
	88	case CPU_DEAD:
	89	case CPU_DEAD_FROZEN:
	90	__oprofile_hrtimer_stop(cpu);
	91	break;
	92	}
	93	return NOTIFY_OK;
1da177e4 LT	94	}
1da177e4 LT	95
bc078e4e MS	96	static struct notifier_block __refdata oprofile_cpu_notifier = {
	97	.notifier_call = oprofile_cpu_notify,
	98	};
1da177e4	99
bc078e4e	100	int __init oprofile_timer_init(struct oprofile_operations *ops)
1da177e4	101	{
bc078e4e MS	102	int rc;
	103
	104	rc = register_hotcpu_notifier(&oprofile_cpu_notifier);
	105	if (rc)
	106	return rc;
1da177e4 LT	107	ops->create_files = NULL;
	108	ops->setup = NULL;
	109	ops->shutdown = NULL;
bc078e4e MS	110	ops->start = oprofile_hrtimer_start;
bc078e4e MS	111	ops->stop = oprofile_hrtimer_stop;
1da177e4	112	ops->cpu_type = "timer";
bc078e4e MS	113	return 0;
	114	}
	115
	116	void __exit oprofile_timer_exit(void)
	117	{
	118	unregister_hotcpu_notifier(&oprofile_cpu_notifier);
1da177e4	119	}