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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event_msr.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event_msr.c7
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/perf_event_msr.c b/arch/x86/kernel/cpu/perf_event_msr.c
index f32ac13934f2..ec863b9a9f78 100644
--- a/arch/x86/kernel/cpu/perf_event_msr.c
+++ b/arch/x86/kernel/cpu/perf_event_msr.c
@@ -163,10 +163,9 @@ again:
goto again;
delta = now - prev;
- if (unlikely(event->hw.event_base == MSR_SMI_COUNT)) {
- delta <<= 32;
- delta >>= 32; /* sign extend */
- }
+ if (unlikely(event->hw.event_base == MSR_SMI_COUNT))
+ delta = sign_extend64(delta, 31);
+
local64_add(now - prev, &event->count);
}