lkml.org 
[lkml]   [2006]   [Apr]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[PATCH] Kconfig.debug: Set DEBUG_MUTEX to off by default
From
Date
Hi,

DEBUG_MUTEX flag is on by default in current kernel configuration.

During performance testing, we saw mutex debug functions like
mutex_debug_check_no_locks_freed (called by kfree()) is expensive as it
goes through a global list of memory areas with mutex lock and do the
checking. For benchmarks such as Volanomark and Hackbench, we have seen
more than 40% drop in performance on some platforms. We suggest to set
DEBUG_MUTEX off by default. Or at least do that later when we feel that
the mutex changes in the current code have stabilized.

Tim Chen

Signed-off-by: Tim Chen <tim.c.chen@intel.com>

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -101,7 +101,7 @@ config DEBUG_PREEMPT

config DEBUG_MUTEXES
bool "Mutex debugging, deadlock detection"
- default y
+ default n
depends on DEBUG_KERNEL
help
This allows mutex semantics violations and mutex related deadlocks

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-04-07 19:29    [W:1.052 / U:0.664 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site