Commit a39d6f25 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf_counter: rework the task clock software counter 



Rework the task clock software counter to use the context time instead
of the task runtime clock, this removes the last such user.

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090406094518.445450972@chello.nl>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 4af4998b

kernel/perf_counter.c

+12 −30
Original line number Diff line number Diff line
@@ -974,9 +974,6 @@ int perf_counter_task_disable(void) 
	curr_rq_lock_irq_save(&flags);

	cpu = smp_processor_id();



	/* force the update of the task clock: */

	__task_delta_exec(curr, 1);



	perf_counter_task_sched_out(curr, cpu);



	spin_lock(&ctx->lock);
@@ -1017,9 +1014,6 @@ int perf_counter_task_enable(void) 
	curr_rq_lock_irq_save(&flags);

	cpu = smp_processor_id();



	/* force the update of the task clock: */

	__task_delta_exec(curr, 1);



	perf_counter_task_sched_out(curr, cpu);



	spin_lock(&ctx->lock);
@@ -2347,38 +2341,28 @@ static const struct hw_perf_counter_ops perf_ops_cpu_clock = { 
 * Software counter: task time clock

 */



/*

 * Called from within the scheduler:

 */

static u64 task_clock_perf_counter_val(struct perf_counter *counter, int update)

{

	struct task_struct *curr = counter->task;

	u64 delta;



	delta = __task_delta_exec(curr, update);



	return curr->se.sum_exec_runtime + delta;

}



static void task_clock_perf_counter_update(struct perf_counter *counter, u64 now)

static void task_clock_perf_counter_update(struct perf_counter *counter)

{

	u64 prev;

	u64 prev, now;

	s64 delta;



	prev = atomic64_read(&counter->hw.prev_count);



	atomic64_set(&counter->hw.prev_count, now);

	update_context_time(counter->ctx);

	now = counter->ctx->time;



	prev = atomic64_xchg(&counter->hw.prev_count, now);

	delta = now - prev;



	atomic64_add(delta, &counter->count);

}



static int task_clock_perf_counter_enable(struct perf_counter *counter)

{

	struct hw_perf_counter *hwc = &counter->hw;

	u64 now;



	update_context_time(counter->ctx);

	now = counter->ctx->time;



	atomic64_set(&hwc->prev_count, task_clock_perf_counter_val(counter, 0));

	atomic64_set(&hwc->prev_count, now);

	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);

	hwc->hrtimer.function = perf_swcounter_hrtimer;

	if (hwc->irq_period) {
@@ -2393,14 +2377,12 @@ static int task_clock_perf_counter_enable(struct perf_counter *counter) 
static void task_clock_perf_counter_disable(struct perf_counter *counter)

{

	hrtimer_cancel(&counter->hw.hrtimer);

	task_clock_perf_counter_update(counter,

			task_clock_perf_counter_val(counter, 0));

	task_clock_perf_counter_update(counter);

}



static void task_clock_perf_counter_read(struct perf_counter *counter)

{

	task_clock_perf_counter_update(counter,

			task_clock_perf_counter_val(counter, 1));

	task_clock_perf_counter_update(counter);

}



static const struct hw_perf_counter_ops perf_ops_task_clock = {

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