lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 19 Oct 2012 14:08:27 +0400 From: Glauber Costa <glommer@...allels.com> To: David Rientjes <rientjes@...gle.com> CC: <linux-mm@...ck.org>, <cgroups@...r.kernel.org>, Mel Gorman <mgorman@...e.de>, Tejun Heo <tj@...nel.org>, Andrew Morton <akpm@...ux-foundation.org>, Michal Hocko <mhocko@...e.cz>, Johannes Weiner <hannes@...xchg.org>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>, Christoph Lameter <cl@...ux.com>, Pekka Enberg <penberg@...nel.org>, <devel@...nvz.org>, <linux-kernel@...r.kernel.org>, Pekka Enberg <penberg@...helsinki.fi> Subject: Re: [PATCH v5 06/14] memcg: kmem controller infrastructure On 10/19/2012 01:59 AM, David Rientjes wrote: > On Thu, 18 Oct 2012, Glauber Costa wrote: > >>>> @@ -2630,6 +2634,171 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg, >>>> memcg_check_events(memcg, page); >>>> } >>>> >>>> +#ifdef CONFIG_MEMCG_KMEM >>>> +static inline bool memcg_can_account_kmem(struct mem_cgroup *memcg) >>>> +{ >>>> + return !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg) && >>>> + (memcg->kmem_accounted & KMEM_ACCOUNTED_MASK); >>>> +} >>>> + >>>> +static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp, u64 size) >>>> +{ >>>> + struct res_counter *fail_res; >>>> + struct mem_cgroup *_memcg; >>>> + int ret = 0; >>>> + bool may_oom; >>>> + >>>> + ret = res_counter_charge(&memcg->kmem, size, &fail_res); >>>> + if (ret) >>>> + return ret; >>>> + >>>> + /* >>>> + * Conditions under which we can wait for the oom_killer. >>>> + * We have to be able to wait, but also, if we can't retry, >>>> + * we obviously shouldn't go mess with oom. >>>> + */ >>>> + may_oom = (gfp & __GFP_WAIT) && !(gfp & __GFP_NORETRY); >>> >>> What about gfp & __GFP_FS? >>> >> >> Do you intend to prevent or allow OOM under that flag? I personally >> think that anything that accepts to be OOM-killed should have GFP_WAIT >> set, so that ought to be enough. >> > > The oom killer in the page allocator cannot trigger without __GFP_FS > because direct reclaim has little chance of being very successful and > thus we end up needlessly killing processes, and that tends to happen > quite a bit if we dont check for it. Seems like this would also happen > with memcg if mem_cgroup_reclaim() has a large probability of failing? > I can indeed see tests for GFP_FS in some key locations in mm/ before calling the OOM Killer. Should I test for GFP_IO as well? If the idea is preventing OOM to trigger for allocations that can write their pages back, how would you feel about the following test: may_oom = (gfp & GFP_KERNEL) && !(gfp & __GFP_NORETRY) ? Michal, what is your take in here? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists