On Tue, 23 Feb 2010 14:49:12 -0800 (PST) David Rientjes <rientjes@xxxxxxxxxx> wrote: > On Tue, 23 Feb 2010, KAMEZAWA Hiroyuki wrote: > > > Ouch, I missed to add memcontrol.h to quilt's reflesh set.. > > This is updated one. Anyway, I'd like to wait for the next mmotm. > > We already have several changes. > > > > I think it would be better to just remove mem_cgroup_out_of_memory() and > make it go through out_of_memory() by specifying a non-NULL pointer to a > struct mem_cgroup. We don't need the duplication in code that these two > functions have and then we can begin to have some consistency with how to > deal with panic_on_oom. > > It would be much better to prefer killing current in pagefault oom > conditions, as the final patch in my oom killer rewrite does, if it is > killable. If not, we scan the tasklist and find another suitable > candidate. If current is bound to a memcg, we pass that to > select_bad_process() so that we only kill other tasks from the same > cgroup. Adding new argument to out_of_memory ? > > This allows us to hijack the TIF_MEMDIE bit to detect when there is a > parallel pagefault oom killing when the oom killer hasn't necessarily been > invoked to kill a system-wide task (it's simply killing current, by > default, and giving it access to memory reserves). Then, we can change > out_of_memory(), which also now handles memcg oom conditions, to always > scan the tasklist first (including for mempolicy and cpuset constrained > ooms), check for any candidates that have TIF_MEMDIE, and return > ERR_PTR(-1UL) if so. That catches the parallel pagefault oom conditions > from needlessly killing memcg tasks. panic_on_oom would only panic after > the tasklist scan has completed and returned != ERR_PTR(-1UL), meaning > pagefault ooms are exempt from that sysctl. > Sorry, I see your concern but I'd like not to do clean-up and bug-fix at the same time. I think clean up after fix is easy in this case. > Anyway, do you think it would be possible to rebase on mmotm with my oom > killer rewrite patches? > They're at > http://www.kernel.org/pub/linux/kernel/people/rientjes/oom-killer-rewrite > I can wait until your patch are merged if necessary. But it seems there will not be much confliction. Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>