From: Yan, Zheng <zheng.z.yan@intel.com>
Date: Wed, 6 May 2015 19:33:52 +0000 (-0400)
Subject: perf/intel/x86: Enlarge the PEBS buffer
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=156174999dd1d0fe8732f5a05f4e9cef921ad487;p=openwrt%2Fstaging%2Fblogic.git

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@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@infradead.org
Cc: eranian@google.com
Link: http://lkml.kernel.org/r/1430940834-8964-7-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 62852470ccbb..266079a3a646 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
 
 /*