[tip:perf/core] perf/intel/x86: Enlarge the PEBS buffer

From: tip-bot for Yan, Zheng
Date: Sun Jun 07 2015 - 13:51:08 EST


Commit-ID: 156174999dd1d0fe8732f5a05f4e9cef921ad487
Gitweb: http://git.kernel.org/tip/156174999dd1d0fe8732f5a05f4e9cef921ad487
Author: Yan, Zheng <zheng.z.yan@xxxxxxxxx>
AuthorDate: Wed, 6 May 2015 15:33:52 -0400
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Sun, 7 Jun 2015 16:08:57 +0200

perf/intel/x86: Enlarge the PEBS buffer

Currently the PEBS buffer size is 4k, it can only hold about 21
PEBS records. This patch enlarges the PEBS buffer size to 64k
(the same as the BTS buffer).

64k memory can hold about 330 PEBS records. This will significantly
reduce the number of PMIs when batched PEBS interrupts are enabled.

Signed-off-by: Yan, Zheng <zheng.z.yan@xxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: acme@xxxxxxxxxxxxx
Cc: eranian@xxxxxxxxxx
Link: http://lkml.kernel.org/r/1430940834-8964-7-git-send-email-kan.liang@xxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
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 6285247..266079a 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

/*
--
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