[PATCH 1/2] perf x86: Make intel_pmu_enable_all to enable only active events

From: Jiri Olsa
Date: Tue Aug 13 2013 - 12:39:47 EST


Currently the intel_pmu_enable_all enables all possible
events, which is not allways desired. One case (there'll
be probably more) is:

- event hits throttling threshold
- NMI stops event
- intel_pmu_enable_all starts it back on the NMI exit

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event_intel.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index a45d8d4..360e7a0 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -912,11 +912,13 @@ static void intel_pmu_disable_all(void)
static void intel_pmu_enable_all(int added)
{
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
+ u64 active_mask = *((u64*) cpuc->active_mask);

intel_pmu_pebs_enable_all();
intel_pmu_lbr_enable_all();
wrmsrl(MSR_CORE_PERF_GLOBAL_CTRL,
- x86_pmu.intel_ctrl & ~cpuc->intel_ctrl_guest_mask);
+ x86_pmu.intel_ctrl & ~cpuc->intel_ctrl_guest_mask
+ & active_mask);

if (test_bit(INTEL_PMC_IDX_FIXED_BTS, cpuc->active_mask)) {
struct perf_event *event =
--
1.7.11.7

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