[PATCH V6 6/6] perf, x86: enlarge PEBS buffer

From: Kan Liang
Date: Thu Apr 09 2015 - 12:39:06 EST


From: Yan, Zheng <zheng.z.yan@xxxxxxxxx>

Currently the PEBS buffer size is 4k, it only can hold about 21
PEBS records. This patch enlarges the PEBS buffer size to 64k
(the same as BTS buffer), 64k memory can hold about 330 PEBS
records. This will significantly the reduce number of PMI when
large PEBS interrupt threshold is used.

Signed-off-by: Yan, Zheng <zheng.z.yan@xxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
---
arch/x86/kernel/cpu/perf_event_intel_ds.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 3d8950a..dfbcaad 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -11,7 +11,7 @@
#define BTS_RECORD_SIZE 24

#define BTS_BUFFER_SIZE (PAGE_SIZE << 4)
-#define PEBS_BUFFER_SIZE PAGE_SIZE
+#define PEBS_BUFFER_SIZE (PAGE_SIZE << 4)
#define PEBS_FIXUP_SIZE PAGE_SIZE

/*
--
1.7.11.7

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