summaryrefslogtreecommitdiffstats
path: root/kernel/sched.c
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2010-09-09 22:27:33 -0700
committerDavid S. Miller <davem@davemloft.net>2010-09-09 22:27:33 -0700
commite548833df83c3554229eff0672900bfe958b45fd (patch)
tree85efc4a76dc356593d6d394776aeb845dc580fb6 /kernel/sched.c
parentcbd9da7be869f676afc204e1a664163778c770bd (diff)
parent053d8f6622701f849fda2ca2c9ae596c13599ba9 (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts: net/mac80211/main.c
Diffstat (limited to 'kernel/sched.c')
-rw-r--r--kernel/sched.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 41541d79e3c..09b574e7f4d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3865,8 +3865,16 @@ int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner)
/*
* Owner changed, break to re-assess state.
*/
- if (lock->owner != owner)
+ if (lock->owner != owner) {
+ /*
+ * If the lock has switched to a different owner,
+ * we likely have heavy contention. Return 0 to quit
+ * optimistic spinning and not contend further:
+ */
+ if (lock->owner)
+ return 0;
break;
+ }
/*
* Is that owner really running on that cpu?