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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_intel.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel.c27
1 files changed, 25 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index fed2ab1f1..760aec1e8 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -1502,7 +1502,15 @@ static __initconst const u64 knl_hw_cache_extra_regs
};
/*
- * Use from PMIs where the LBRs are already disabled.
+ * Used from PMIs where the LBRs are already disabled.
+ *
+ * This function could be called consecutively. It is required to remain in
+ * disabled state if called consecutively.
+ *
+ * During consecutive calls, the same disable value will be written to related
+ * registers, so the PMU state remains unchanged. hw.state in
+ * intel_bts_disable_local will remain PERF_HES_STOPPED too in consecutive
+ * calls.
*/
static void __intel_pmu_disable_all(void)
{
@@ -1884,6 +1892,16 @@ again:
if (__test_and_clear_bit(62, (unsigned long *)&status)) {
handled++;
x86_pmu.drain_pebs(regs);
+ /*
+ * There are cases where, even though, the PEBS ovfl bit is set
+ * in GLOBAL_OVF_STATUS, the PEBS events may also have their
+ * overflow bits set for their counters. We must clear them
+ * here because they have been processed as exact samples in
+ * the drain_pebs() routine. They must not be processed again
+ * in the for_each_bit_set() loop for regular samples below.
+ */
+ status &= ~cpuc->pebs_enabled;
+ status &= x86_pmu.intel_ctrl | GLOBAL_STATUS_TRACE_TOPAPMI;
}
/*
@@ -1929,7 +1947,10 @@ again:
goto again;
done:
- __intel_pmu_enable_all(0, true);
+ /* Only restore PMU state when it's active. See x86_pmu_disable(). */
+ if (cpuc->enabled)
+ __intel_pmu_enable_all(0, true);
+
/*
* Only unmask the NMI after the overflow counters
* have been reset. This avoids spurious NMIs on
@@ -3396,6 +3417,7 @@ __init int intel_pmu_init(void)
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] =
X86_CONFIG(.event=0xb1, .umask=0x3f, .inv=1, .cmask=1);
+ intel_pmu_pebs_data_source_nhm();
x86_add_quirk(intel_nehalem_quirk);
pr_cont("Nehalem events, ");
@@ -3459,6 +3481,7 @@ __init int intel_pmu_init(void)
intel_perfmon_event_map[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] =
X86_CONFIG(.event=0xb1, .umask=0x3f, .inv=1, .cmask=1);
+ intel_pmu_pebs_data_source_nhm();
pr_cont("Westmere events, ");
break;