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 <[email protected]>
Signed-off-by: Kan Liang <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 62852470ccbbe26634d402f791b81dc41df7d964..266079a3a64652d91c74e3767003e56281e3bc71 100644 (file)
--- 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
 
 /*