perf: Reduce perf_disable() usage
Since the current perf_disable() usage is only an optimization,
remove it for now. This eases the removal of the __weak
hw_perf_enable() interface.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: paulus <paulus@samba.org>
Cc: stephane eranian <eranian@googlemail.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Yanmin <yanmin_zhang@linux.intel.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Cc: David Miller <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 149ca18..9a98ce9 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -478,11 +478,6 @@
return;
raw_spin_lock(&ctx->lock);
- /*
- * Protect the list operation against NMI by disabling the
- * events on a global level.
- */
- perf_disable();
event_sched_out(event, cpuctx, ctx);
@@ -498,7 +493,6 @@
perf_max_events - perf_reserved_percpu);
}
- perf_enable();
raw_spin_unlock(&ctx->lock);
}
@@ -803,12 +797,6 @@
ctx->is_active = 1;
update_context_time(ctx);
- /*
- * Protect the list operation against NMI by disabling the
- * events on a global level. NOP for non NMI based events.
- */
- perf_disable();
-
add_event_to_ctx(event, ctx);
if (event->cpu != -1 && event->cpu != smp_processor_id())
@@ -850,8 +838,6 @@
cpuctx->max_pertask--;
unlock:
- perf_enable();
-
raw_spin_unlock(&ctx->lock);
}
@@ -972,12 +958,10 @@
if (!group_can_go_on(event, cpuctx, 1)) {
err = -EEXIST;
} else {
- perf_disable();
if (event == leader)
err = group_sched_in(event, cpuctx, ctx);
else
err = event_sched_in(event, cpuctx, ctx);
- perf_enable();
}
if (err) {
@@ -1090,9 +1074,8 @@
goto out;
update_context_time(ctx);
- perf_disable();
if (!ctx->nr_active)
- goto out_enable;
+ goto out;
if (event_type & EVENT_PINNED) {
list_for_each_entry(event, &ctx->pinned_groups, group_entry)
@@ -1103,9 +1086,6 @@
list_for_each_entry(event, &ctx->flexible_groups, group_entry)
group_sched_out(event, cpuctx, ctx);
}
-
- out_enable:
- perf_enable();
out:
raw_spin_unlock(&ctx->lock);
}
@@ -1364,8 +1344,6 @@
ctx->timestamp = perf_clock();
- perf_disable();
-
/*
* First go through the list and put on any pinned groups
* in order to give them the best chance of going on.
@@ -1377,7 +1355,6 @@
if (event_type & EVENT_FLEXIBLE)
ctx_flexible_sched_in(ctx, cpuctx);
- perf_enable();
out:
raw_spin_unlock(&ctx->lock);
}
@@ -1425,8 +1402,6 @@
if (cpuctx->task_ctx == ctx)
return;
- perf_disable();
-
/*
* We want to keep the following priority order:
* cpu pinned (that don't need to move), task pinned,
@@ -1439,8 +1414,6 @@
ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE);
cpuctx->task_ctx = ctx;
-
- perf_enable();
}
#define MAX_INTERRUPTS (~0ULL)
@@ -1555,11 +1528,9 @@
hwc->sample_period = sample_period;
if (local64_read(&hwc->period_left) > 8*sample_period) {
- perf_disable();
perf_event_stop(event);
local64_set(&hwc->period_left, 0);
perf_event_start(event);
- perf_enable();
}
}
@@ -1588,15 +1559,12 @@
*/
if (interrupts == MAX_INTERRUPTS) {
perf_log_throttle(event, 1);
- perf_disable();
event->pmu->unthrottle(event);
- perf_enable();
}
if (!event->attr.freq || !event->attr.sample_freq)
continue;
- perf_disable();
event->pmu->read(event);
now = local64_read(&event->count);
delta = now - hwc->freq_count_stamp;
@@ -1604,7 +1572,6 @@
if (delta > 0)
perf_adjust_period(event, TICK_NSEC, delta);
- perf_enable();
}
raw_spin_unlock(&ctx->lock);
}
@@ -1647,7 +1614,6 @@
if (!rotate)
return;
- perf_disable();
cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_out(ctx, EVENT_FLEXIBLE);
@@ -1659,7 +1625,6 @@
cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE);
if (ctx)
task_ctx_sched_in(curr, EVENT_FLEXIBLE);
- perf_enable();
}
static int event_enable_on_exec(struct perf_event *event,