Re: [PATCH 4/6] cgroups: forbid pre_destroy callback to fail
From: Li Zefan <hidden>
Date: 2012-10-19 09:33:56
Also in:
linux-mm, lkml
From: Li Zefan <hidden>
Date: 2012-10-19 09:33:56
Also in:
linux-mm, lkml
On 2012/10/17 21:30, Michal Hocko wrote:
Now that mem_cgroup_pre_destroy callback doesn't fail finally we can safely move on and forbit all the callbacks to fail. The last missing piece is moving cgroup_call_pre_destroy after cgroup_clear_css_refs so that css_tryget fails so no new charges for the memcg can happen.
The callbacks are also called from within cgroup_lock to guarantee that no new tasks show up.
I'm afraid this won't work. See commit 3fa59dfbc3b223f02c26593be69ce6fc9a940405
("cgroup: fix potential deadlock in pre_destroy")
We could theoretically call them outside of the lock but then we have to move after CGRP_REMOVED flag is set. Signed-off-by: Michal Hocko <redacted> --- kernel/cgroup.c | 30 +++++++++--------------------- 1 file changed, 9 insertions(+), 21 deletions(-)
-- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>