[tip:perf/core] perf: Limit callchains to 127

[tip-bot for Arun Sharma]

Commit-ID:  0b0d9cf6ec7bab91977da2d71c09157f110f7c2e
Gitweb:     http://git.kernel.org/tip/0b0d9cf6ec7bab91977da2d71c09157f110f7c2e
Author:     Arun Sharma <asharma@xxxxxx>
AuthorDate: Fri, 20 Apr 2012 15:41:34 -0700
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 6 Jun 2012 17:08:00 +0200

perf: Limit callchains to 127

Stack depth of 255 seems excessive, given that copy_from_user_nmi()
could be slow.

Signed-off-by: Arun Sharma <asharma@xxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Link: http://lkml.kernel.org/r/1334961696-19580-3-git-send-email-asharma@xxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 include/linux/perf_event.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 1817d40..45db49f 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -555,7 +555,7 @@ enum perf_event_type {
 	PERF_RECORD_MAX,			/* non-ABI */
 };
 
-#define PERF_MAX_STACK_DEPTH		255
+#define PERF_MAX_STACK_DEPTH		127
 
 enum perf_callchain_context {
 	PERF_CONTEXT_HV			= (__u64)-32,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/