perf counters: clean up state transitions
Impact: cleanup
Introduce a proper enum for the 3 states of a counter:
PERF_COUNTER_STATE_OFF = -1
PERF_COUNTER_STATE_INACTIVE = 0
PERF_COUNTER_STATE_ACTIVE = 1
and rename counter->active to counter->state and propagate the
changes everywhere.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index 4e679b9..559130b 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -167,9 +167,9 @@
spin_lock(&ctx->lock);
- if (counter->active) {
+ if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
counter->hw_ops->hw_perf_counter_disable(counter);
- counter->active = 0;
+ counter->state = PERF_COUNTER_STATE_INACTIVE;
ctx->nr_active--;
cpuctx->active_oncpu--;
counter->task = NULL;
@@ -281,7 +281,7 @@
if (cpuctx->active_oncpu < perf_max_counters) {
counter->hw_ops->hw_perf_counter_enable(counter);
- counter->active = 1;
+ counter->state = PERF_COUNTER_STATE_ACTIVE;
counter->oncpu = cpu;
ctx->nr_active++;
cpuctx->active_oncpu++;
@@ -328,7 +328,6 @@
spin_lock_irq(&ctx->lock);
/*
- * If the context is active and the counter has not been added
* we need to retry the smp call.
*/
if (ctx->nr_active && list_empty(&counter->list_entry)) {
@@ -353,12 +352,12 @@
struct perf_cpu_context *cpuctx,
struct perf_counter_context *ctx)
{
- if (!counter->active)
+ if (counter->state != PERF_COUNTER_STATE_ACTIVE)
return;
counter->hw_ops->hw_perf_counter_disable(counter);
- counter->active = 0;
- counter->oncpu = -1;
+ counter->state = PERF_COUNTER_STATE_INACTIVE;
+ counter->oncpu = -1;
cpuctx->active_oncpu--;
ctx->nr_active--;
@@ -415,11 +414,11 @@
struct perf_counter_context *ctx,
int cpu)
{
- if (counter->active == -1)
+ if (counter->state == PERF_COUNTER_STATE_OFF)
return;
counter->hw_ops->hw_perf_counter_enable(counter);
- counter->active = 1;
+ counter->state = PERF_COUNTER_STATE_ACTIVE;
counter->oncpu = cpu; /* TODO: put 'cpu' into cpuctx->cpu */
cpuctx->active_oncpu++;
@@ -506,8 +505,8 @@
perf_flags = hw_perf_save_disable();
list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- WARN_ON_ONCE(counter->active == 1);
- counter->active = -1;
+ WARN_ON_ONCE(counter->state == PERF_COUNTER_STATE_ACTIVE);
+ counter->state = PERF_COUNTER_STATE_OFF;
}
hw_perf_restore(perf_flags);
@@ -540,9 +539,9 @@
perf_flags = hw_perf_save_disable();
list_for_each_entry(counter, &ctx->counter_list, list_entry) {
- if (counter->active != -1)
+ if (counter->state != PERF_COUNTER_STATE_OFF)
continue;
- counter->active = 0;
+ counter->state = PERF_COUNTER_STATE_INACTIVE;
}
hw_perf_restore(perf_flags);
@@ -620,7 +619,7 @@
* If counter is enabled and currently active on a CPU, update the
* value in the counter structure:
*/
- if (counter->active) {
+ if (counter->state == PERF_COUNTER_STATE_ACTIVE) {
smp_call_function_single(counter->oncpu,
__hw_perf_counter_read, counter, 1);
}
@@ -673,7 +672,7 @@
retry:
spin_lock_irq(&ctx->lock);
- if (!counter->active) {
+ if (counter->state != PERF_COUNTER_STATE_ACTIVE) {
counter->irqdata = counter->usrdata;
counter->usrdata = oldirqdata;
spin_unlock_irq(&ctx->lock);