Messages in this thread | | | Subject | Re: [PATCH 0/2 v8] oom: capture unreclaimable slab info in oom message | From | "Yang Shi" <> | Date | Mon, 02 Oct 2017 23:46:14 +0800 |
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On 10/2/17 4:20 AM, Michal Hocko wrote: > On Thu 28-09-17 13:36:57, Tetsuo Handa wrote: >> On 2017/09/28 6:46, Yang Shi wrote: >>> Changelog v7 —> v8: >>> * Adopted Michal’s suggestion to dump unreclaim slab info when unreclaimable slabs amount > total user memory. Not only in oom panic path. >> >> Holding slab_mutex inside dump_unreclaimable_slab() was refrained since V2 >> because there are >> >> mutex_lock(&slab_mutex); >> kmalloc(GFP_KERNEL); >> mutex_unlock(&slab_mutex); >> >> users. If we call dump_unreclaimable_slab() for non OOM panic path, aren't we >> introducing a risk of crash (i.e. kernel panic) for regular OOM path? > > yes we are > >> We can try mutex_trylock() from dump_unreclaimable_slab() at best. >> But it is still remaining unsafe, isn't it? > > using the trylock sounds like a reasonable compromise.
OK, it sounds we reach agreement on trylock. Will solve those comments in v9.
Thanks, Yang
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