path: root/kernel
diff options
authorMandeep Singh Baines <msb@chromium.org>2011-01-13 15:46:05 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-13 17:32:35 -0800
commitdabb16f639820267b3850d804571c70bd93d4e07 (patch)
tree7da59e6133cd2f820389574ac9206c56e046f5d4 /kernel
parentd0a21265dfb5fa8ae54e90d0fb6d1c215b10a28a (diff)
oom: allow a non-CAP_SYS_RESOURCE proces to oom_score_adj down
We'd like to be able to oom_score_adj a process up/down as it enters/leaves the foreground. Currently, it is not possible to oom_adj down without CAP_SYS_RESOURCE. This patch allows a task to decrease its oom_score_adj back to the value that a CAP_SYS_RESOURCE thread set it to or its inherited value at fork. Assuming the thread that has forked it has oom_score_adj of 0, each process could decrease it back from 0 upon activation unless a CAP_SYS_RESOURCE thread elevated it to something higher. Alternative considered: * a setuid binary * a daemon with CAP_SYS_RESOURCE Since you don't wan't all processes to be able to reduce their oom_adj, a setuid or daemon implementation would be complex. The alternatives also have much higher overhead. This patch updated from original patch based on feedback from David Rientjes. Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Acked-by: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 76a1fdd80bd..1499607e4da 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -910,6 +910,7 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
sig->oom_adj = current->signal->oom_adj;
sig->oom_score_adj = current->signal->oom_score_adj;
+ sig->oom_score_adj_min = current->signal->oom_score_adj_min;