perf, x86, Do not user perf_disable from NMI context

Explicitly use intel_pmu_{disable,enable}_all() in intel_pmu_handle_irq()
to avoid the NMI race conditions in perf_{disable,enable}

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>

1 files changed, 5 insertions, 6 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 12e811a7d747..c582449163fa 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -745,11 +745,11 @@ static int intel_pmu_handle_irq(struct pt_regs *regs)
 
         cpuc = &__get_cpu_var(cpu_hw_events);
 
-        perf_disable();
+        intel_pmu_disable_all();
         intel_pmu_drain_bts_buffer();
         status = intel_pmu_get_status();
         if (!status) {
-                perf_enable();
+                intel_pmu_enable_all();
                 return 0;
         }
 
@@ -759,8 +759,7 @@ again:
                 WARN_ONCE(1, "perfevents: irq loop stuck!\n");
                 perf_event_print_debug();
                 intel_pmu_reset();
-                perf_enable();
-                return 1;
+                goto done;
         }
 
         inc_irq_stat(apic_perf_irqs);
@@ -790,8 +789,8 @@ again:
         if (status)
                 goto again;
 
-        perf_enable();
-
+done:
+        intel_pmu_enable_all();
         return 1;
 }