From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9AE13C4646B for ; Mon, 24 Jun 2019 21:27:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 644E020663 for ; Mon, 24 Jun 2019 21:27:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="nSpH5bFJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728711AbfFXV1D (ORCPT ); Mon, 24 Jun 2019 17:27:03 -0400 Received: from mail-pg1-f201.google.com ([209.85.215.201]:50110 "EHLO mail-pg1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726331AbfFXV1C (ORCPT ); Mon, 24 Jun 2019 17:27:02 -0400 Received: by mail-pg1-f201.google.com with SMTP id 30so10111977pgk.16 for ; Mon, 24 Jun 2019 14:27:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=jaauUWabecQwQ5Q70jIH+5Q73ClPU59UVRRBap690W4=; b=nSpH5bFJw8ezGsmwSi2rzrMus3Anp17johkJQyAG2G7JqAbelPEdakMFH/NdyTRVMs /WANijmqB6eW00w3FD76Vz5V99NvA/I4Pc6f8GmNVCGaUu27vJOZ9K94Rb9Oe9og5O/F /nOQdJ/ZP8YHEC95IARa7HQAeD4lFqpQ26YotsUNWvKqgtcuy4lJyT5EXgbHyjuYRnl2 xYzXwc17gUgxRiz2RXZjXE880Ewkd5JcotUXdCw/6a69vxVqyMrkU7QV/yrpNx7Jz/qw LwEwckhismEjUaUDYJ6YIN/zeUPdYbx8Q6FsfxYe1puMIqRTfmwB8U0HbhPkRZrZJ8/0 s2Bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=jaauUWabecQwQ5Q70jIH+5Q73ClPU59UVRRBap690W4=; b=QqgstTuZtMuypfkuEsKJ4mmP80pBkLQKKiDm7LfCe4bNWnCXTGcswVycSFExi3Xo4R 0WbM6QkkTD/8rbOX2ju5FOx20BLqAh1bMXmO0ACFqRRc/FPpgOtf5rkZGLVSzm0uEX6L 4URT5qnVK9FYcvdR5uZCcNieE4ltAaJVng5RxCoUvwn9UUCOnUUOPqMMECYcXgC5Rnag JfTgHZzxlpJ2sgZX6bslB6bucQqz2q3zZwlERJNp8sXmTLJTInutySRULAj6yb5T/Mct 2yGNiokzgyfb8yZDXdvKp46TJ+x+ly29wWsC+cIZO3WxA4jC3PdKkbUGCDX+lM4WyvzM XZ6g== X-Gm-Message-State: APjAAAUvbxMF9YTf+Tk6wZdBSwOIcLTYJpSnkcD8/734F8v3fq97UpGq glMveCzIrbBP+AqYABkLERiF2W6dmvhBHw== X-Google-Smtp-Source: APXvYqxTVYyeiEGbsAPD+rbQmU7OP+F2TEhzLPCSQtqirFtgy0xbSaaq9tQz4tKPecocEomfIoNzNROavMVt+w== X-Received: by 2002:a63:8c0f:: with SMTP id m15mr12981076pgd.441.1561411621640; Mon, 24 Jun 2019 14:27:01 -0700 (PDT) Date: Mon, 24 Jun 2019 14:26:30 -0700 In-Reply-To: <20190624212631.87212-1-shakeelb@google.com> Message-Id: <20190624212631.87212-2-shakeelb@google.com> Mime-Version: 1.0 References: <20190624212631.87212-1-shakeelb@google.com> X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog Subject: [PATCH v3 2/3] mm, oom: remove redundant task_in_mem_cgroup() check From: Shakeel Butt To: Johannes Weiner , Vladimir Davydov , Michal Hocko , Andrew Morton , Roman Gushchin , David Rientjes , KOSAKI Motohiro , Tetsuo Handa , Paul Jackson , Nick Piggin Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shakeel Butt Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org oom_unkillable_task() can be called from three different contexts i.e. global OOM, memcg OOM and oom_score procfs interface. At the moment oom_unkillable_task() does a task_in_mem_cgroup() check on the given process. Since there is no reason to perform task_in_mem_cgroup() check for global OOM and oom_score procfs interface, those contexts provide NULL memcg and skips the task_in_mem_cgroup() check. However for memcg OOM context, the oom_unkillable_task() is always called from mem_cgroup_scan_tasks() and thus task_in_mem_cgroup() check becomes redundant. So, just remove the task_in_mem_cgroup() check altogether. Signed-off-by: Shakeel Butt Signed-off-by: Tetsuo Handa --- Changelog since v2: - Further divided the patch into two patches. - Incorporated the task_in_mem_cgroup() from Tetsuo. Changelog since v1: - Divide the patch into two patches. fs/proc/base.c | 2 +- include/linux/memcontrol.h | 7 ------- include/linux/oom.h | 2 +- mm/memcontrol.c | 26 -------------------------- mm/oom_kill.c | 19 +++++++------------ 5 files changed, 9 insertions(+), 47 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index b8d5d100ed4a..5eacce5e924a 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -532,7 +532,7 @@ static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns, unsigned long totalpages = totalram_pages() + total_swap_pages; unsigned long points = 0; - points = oom_badness(task, NULL, NULL, totalpages) * + points = oom_badness(task, NULL, totalpages) * 1000 / totalpages; seq_printf(m, "%lu\n", points); diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 9abf31bbe53a..2cbce1fe7780 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -407,7 +407,6 @@ static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat, struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *); -bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg); struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); @@ -896,12 +895,6 @@ static inline bool mm_match_cgroup(struct mm_struct *mm, return true; } -static inline bool task_in_mem_cgroup(struct task_struct *task, - const struct mem_cgroup *memcg) -{ - return true; -} - static inline struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm) { return NULL; diff --git a/include/linux/oom.h b/include/linux/oom.h index d07992009265..b75104690311 100644 --- a/include/linux/oom.h +++ b/include/linux/oom.h @@ -108,7 +108,7 @@ static inline vm_fault_t check_stable_address_space(struct mm_struct *mm) bool __oom_reap_task_mm(struct mm_struct *mm); extern unsigned long oom_badness(struct task_struct *p, - struct mem_cgroup *memcg, const nodemask_t *nodemask, + const nodemask_t *nodemask, unsigned long totalpages); extern bool out_of_memory(struct oom_control *oc); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index db46a9dc37ab..27c92c2b99be 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1259,32 +1259,6 @@ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru, *lru_size += nr_pages; } -bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg) -{ - struct mem_cgroup *task_memcg; - struct task_struct *p; - bool ret; - - p = find_lock_task_mm(task); - if (p) { - task_memcg = get_mem_cgroup_from_mm(p->mm); - task_unlock(p); - } else { - /* - * All threads may have already detached their mm's, but the oom - * killer still needs to detect if they have already been oom - * killed to prevent needlessly killing additional tasks. - */ - rcu_read_lock(); - task_memcg = mem_cgroup_from_task(task); - css_get(&task_memcg->css); - rcu_read_unlock(); - } - ret = mem_cgroup_is_descendant(task_memcg, memcg); - css_put(&task_memcg->css); - return ret; -} - /** * mem_cgroup_margin - calculate chargeable space of a memory cgroup * @memcg: the memory cgroup diff --git a/mm/oom_kill.c b/mm/oom_kill.c index bd80997e0969..e0cdcbd58b0b 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -153,17 +153,13 @@ static inline bool is_memcg_oom(struct oom_control *oc) /* return true if the task is not adequate as candidate victim task. */ static bool oom_unkillable_task(struct task_struct *p, - struct mem_cgroup *memcg, const nodemask_t *nodemask) + const nodemask_t *nodemask) { if (is_global_init(p)) return true; if (p->flags & PF_KTHREAD) return true; - /* When mem_cgroup_out_of_memory() and p is not member of the group */ - if (memcg && !task_in_mem_cgroup(p, memcg)) - return true; - /* p may not have freeable memory in nodemask */ if (!has_intersects_mems_allowed(p, nodemask)) return true; @@ -194,20 +190,19 @@ static bool is_dump_unreclaim_slabs(void) * oom_badness - heuristic function to determine which candidate task to kill * @p: task struct of which task we should calculate * @totalpages: total present RAM allowed for page allocation - * @memcg: task's memory controller, if constrained * @nodemask: nodemask passed to page allocator for mempolicy ooms * * The heuristic for determining which task to kill is made to be as simple and * predictable as possible. The goal is to return the highest value for the * task consuming the most memory to avoid subsequent oom failures. */ -unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg, +unsigned long oom_badness(struct task_struct *p, const nodemask_t *nodemask, unsigned long totalpages) { long points; long adj; - if (oom_unkillable_task(p, memcg, nodemask)) + if (oom_unkillable_task(p, nodemask)) return 0; p = find_lock_task_mm(p); @@ -318,7 +313,7 @@ static int oom_evaluate_task(struct task_struct *task, void *arg) struct oom_control *oc = arg; unsigned long points; - if (oom_unkillable_task(task, NULL, oc->nodemask)) + if (oom_unkillable_task(task, oc->nodemask)) goto next; /* @@ -342,7 +337,7 @@ static int oom_evaluate_task(struct task_struct *task, void *arg) goto select; } - points = oom_badness(task, NULL, oc->nodemask, oc->totalpages); + points = oom_badness(task, oc->nodemask, oc->totalpages); if (!points || points < oc->chosen_points) goto next; @@ -390,7 +385,7 @@ static int dump_task(struct task_struct *p, void *arg) struct oom_control *oc = arg; struct task_struct *task; - if (oom_unkillable_task(p, NULL, oc->nodemask)) + if (oom_unkillable_task(p, oc->nodemask)) return 0; task = find_lock_task_mm(p); @@ -1090,7 +1085,7 @@ bool out_of_memory(struct oom_control *oc) check_panic_on_oom(oc, constraint); if (!is_memcg_oom(oc) && sysctl_oom_kill_allocating_task && - current->mm && !oom_unkillable_task(current, NULL, oc->nodemask) && + current->mm && !oom_unkillable_task(current, oc->nodemask) && current->signal->oom_score_adj != OOM_SCORE_ADJ_MIN) { get_task_struct(current); oc->chosen = current; -- 2.22.0.410.gd8fdbe21b5-goog