From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 75818900117 for ; Tue, 4 Oct 2011 02:32:50 -0400 (EDT) Message-ID: <4E8AA866.3010509@parallels.com> Date: Tue, 4 Oct 2011 10:32:06 +0400 From: Glauber Costa MIME-Version: 1.0 Subject: Re: [PATCH v4 3/8] foundations of per-cgroup memory pressure controlling. References: <1317637123-18306-1-git-send-email-glommer@parallels.com> <1317637123-18306-4-git-send-email-glommer@parallels.com> <20111004095715.479da44d.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20111004095715.479da44d.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: KAMEZAWA Hiroyuki Cc: linux-kernel@vger.kernel.org, paul@paulmenage.org, lizf@cn.fujitsu.com, ebiederm@xmission.com, davem@davemloft.net, gthelen@google.com, netdev@vger.kernel.org, linux-mm@kvack.org, kirill@shutemov.name, avagin@parallels.com On 10/04/2011 04:57 AM, KAMEZAWA Hiroyuki wrote: > On Mon, 3 Oct 2011 14:18:38 +0400 > Glauber Costa wrote: > >> This patch converts struct sock fields memory_pressure, >> memory_allocated, sockets_allocated, and sysctl_mem (now prot_mem) >> to function pointers, receiving a struct mem_cgroup parameter. >> >> enter_memory_pressure is kept the same, since all its callers >> have socket a context, and the kmem_cgroup can be derived from >> the socket itself. >> >> To keep things working, the patch convert all users of those fields >> to use acessor functions. >> >> In my benchmarks I didn't see a significant performance difference >> with this patch applied compared to a baseline (around 1 % diff, thus >> inside error margin). >> >> Signed-off-by: Glauber Costa >> CC: David S. Miller >> CC: Hiroyouki Kamezawa >> CC: Eric W. Biederman > > A nitpick. > > >> #ifdef CONFIG_INET >> struct sock; >> +struct proto; >> #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM >> void sock_update_memcg(struct sock *sk); >> void sock_release_memcg(struct sock *sk); >> - >> +void memcg_sock_mem_alloc(struct mem_cgroup *mem, struct proto *prot, >> + int amt, int *parent_failure); >> +void memcg_sock_mem_free(struct mem_cgroup *mem, struct proto *prot, int amt); >> +void memcg_sockets_allocated_dec(struct mem_cgroup *mem, struct proto *prot); >> +void memcg_sockets_allocated_inc(struct mem_cgroup *mem, struct proto *prot); >> #else >> +/* memcontrol includes sockets.h, that includes memcontrol.h ... */ >> +static inline void memcg_sock_mem_alloc(struct mem_cgroup *mem, >> + struct proto *prot, int amt, >> + int *parent_failure) >> +{ >> +} > > In these days, at naming memory cgroup pointers, we use "memcg" instead of > "mem". So, could you use "memcg" for represeinting memory cgroup ? > > >> + >> +void memcg_sock_mem_alloc(struct mem_cgroup *mem, struct proto *prot, >> + int amt, int *parent_failure) >> +{ >> + mem = parent_mem_cgroup(mem); >> + for (; mem != NULL; mem = parent_mem_cgroup(mem)) { >> + long alloc; >> + long *prot_mem = prot->prot_mem(mem); >> + /* >> + * Large nestings are not the common case, and stopping in the >> + * middle would be complicated enough, that we bill it all the >> + * way through the root, and if needed, unbill everything later >> + */ >> + alloc = atomic_long_add_return(amt, >> + prot->memory_allocated(mem)); >> + *parent_failure |= (alloc> prot_mem[2]); >> + } >> +} >> +EXPORT_SYMBOL(memcg_sock_mem_alloc); > > Hmm. why not using res_counter ? for reusing 'unbill' code ? > Well, res_counters are slightly more expensive than needed here, since we need to clear interrupts and hold a spinlock. No particular reason besides it. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org