path: root/mm
diff options
authorDavid Rientjes <rientjes@google.com>2009-06-16 15:33:16 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-16 19:47:45 -0700
commit81236810226f71bd9ff77321c8e8276dae7efc61 (patch)
tree8194006c780be40bfac49a2c557ab037186a57e9 /mm
parent9198e96c06744517e3b18fce8be6db61e96a3227 (diff)
oom: only oom kill exiting tasks with attached memory
When a task is chosen for oom kill and is found to be PF_EXITING, __oom_kill_task() is called to elevate the task's timeslice and give it access to memory reserves so that it may quickly exit. This privilege is unnecessary, however, if the task has already detached its mm. Although its possible for the mm to become detached later since task_lock() is not held, __oom_kill_task() will simply be a no-op in such circumstances. Subsequently, it is no longer necessary to warn about killing mm-less tasks since it is a no-op. Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: Rik van Riel <riel@redhat.com> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Minchan Kim <minchan.kim@gmail.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 3 insertions, 5 deletions
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index cdcf89cb9ff..175a67a78a9 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -325,11 +325,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose)
- if (!p->mm) {
- WARN_ON(1);
- printk(KERN_WARNING "tried to kill an mm-less task!\n");
+ if (!p->mm)
- }
if (verbose)
printk(KERN_ERR "Killed process %d (%s)\n",
@@ -397,8 +394,9 @@ static int oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
* If the task is already exiting, don't alarm the sysadmin or kill
* its children or threads, just set TIF_MEMDIE so it can die quickly
+ * if its mm is still attached.
- if (p->flags & PF_EXITING) {
+ if (p->mm && (p->flags & PF_EXITING)) {
__oom_kill_task(p, 0);
return 0;