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[tip:perf/pebs] perf, x86: Fix pebs drains

10 Mar 2010
Posted by Peter Zijlstra

perf, x86: Fix pebs drains

I overlooked the perf_disable()/perf_enable() calls in
intel_pmu_handle_irq(), (pointed out by Markus) so we should not
explicitly disable_all/enable_all pebs counters in the drain functions,
these are already disabled and enabling them early is confusing.

Signed-off-by: Peter Zijlstra
Cc: Arnaldo Carvalho de Melo
Cc:
paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference:
Signed-off-by: Ingo Molnar
---
arch/x86/kernel/cpu/perf_event_intel_ds.c | 15 +++------------
1 files changed, 3 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index a7401e4..66c6962 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -476,18 +476,16 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
if (!event || !ds || !x86_pmu.pebs)
return;

- intel_pmu_pebs_disable_all();
-
at = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base;
top = (struct pebs_record_core *)(unsigned long)ds->pebs_index;

if (top <= at)
- goto out;
+ return;

ds->pebs_index = ds->pebs_buffer_base;

if (!intel_pmu_save_and_restart(event))
- goto out;
+ return;

perf_sample_data_init(&data, 0);
data.period = event->hw.last_period;
@@ -528,9 +526,6 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)

if (perf_event_overflow(event, 1, &data, &regs))
x86_pmu_stop(event);
-
-out:
- intel_pmu_pebs_enable_all();
}

static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
@@ -547,13 +542,11 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
if (!ds || !x86_pmu.pebs)
return;

- intel_pmu_pebs_disable_all();
-
at = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;

if (top <= at)
- goto out;
+ return;

ds->pebs_index = ds->pebs_buffer_base;

@@ -604,8 +597,6 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
if (perf_event_overflow(event, 1, &data, &regs))
x86_pmu_stop(event);
}
-out:
- intel_pmu_pebs_enable_all();
}

/*
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