perf, x86: Deal with multiple state bits for pebs-fmt1

Its unclear if the PEBS state record will have only a single bit set, in
case it does not and accumulates bits, deal with that by only processing
each event once.

Also, robustify some of the code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 9ad0e67b9c820dd426514e9bda2aef5d2d22edbc..b4680daecf19fc5681bb14f4e294134adae14031 100644 (file)
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -538,6 +538,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
        struct perf_event *event = NULL;
        struct perf_raw_record raw;
        struct pt_regs regs;
+       u64 status = 0;
        int bit, n;
 
        if (!ds || !x86_pmu.pebs)
@@ -561,13 +562,22 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
 
        for ( ; at < top; at++) {
                for_each_bit(bit, (unsigned long *)&at->status, MAX_PEBS_EVENTS) {
-                       if (!cpuc->events[bit]->attr.precise)
+                       event = cpuc->events[bit];
+                       if (!test_bit(bit, cpuc->active_mask))
                                continue;
 
-                       event = cpuc->events[bit];
+                       WARN_ON_ONCE(!event);
+
+                       if (!event->attr.precise)
+                               continue;
+
+                       if (__test_and_set_bit(bit, (unsigned long *)&status))
+                               continue;
+
+                       break;
                }
 
-               if (!event)
+               if (!event || bit >= MAX_PEBS_EVENTS)
                        continue;
 
                if (!intel_pmu_save_and_restart(event))