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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B1DD5C433B4 for ; Fri, 30 Apr 2021 05:56:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95B806147E for ; Fri, 30 Apr 2021 05:56:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229591AbhD3F5b (ORCPT ); Fri, 30 Apr 2021 01:57:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:50242 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229508AbhD3F5a (ORCPT ); Fri, 30 Apr 2021 01:57:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C6AC461476; Fri, 30 Apr 2021 05:56:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1619762203; bh=Bgvt5zu4e55Z5ZnAslXfwKZ9YNg5hLH3pvLoIBqFf6g=; h=Date:From:To:Subject:In-Reply-To:From; b=NW5eG/OSzkE+TDzH9u50rFpObOLIO/p/NecyECXNGiKsy1dbkAnLSbHVy+EgPHkNA X5ZrF5mAzdTQDpUBPHEQN6fWlG2WG3Ju2yDlV9j+pUqFe2Uz/84Lv/s4RAkiIrSiq4 dhJAqRICNq+weTukD5iwzbjAYTptlFpRys+tzYSY= Date: Thu, 29 Apr 2021 22:56:42 -0700 From: Andrew Morton To: akpm@linux-foundation.org, duanxiongchun@bytedance.com, guro@fb.com, hannes@cmpxchg.org, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, shakeelb@google.com, songmuchun@bytedance.com, torvalds@linux-foundation.org, vdavydov.dev@gmail.com Subject: [patch 069/178] mm: memcontrol: introduce obj_cgroup_{un}charge_pages Message-ID: <20210430055642.sFElfIOEQ%akpm@linux-foundation.org> In-Reply-To: <20210429225251.02b6386d21b69255b4f6c163@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Muchun Song Subject: mm: memcontrol: introduce obj_cgroup_{un}charge_pages We know that the unit of slab object charging is bytes, the unit of kmem page charging is PAGE_SIZE. If we want to reuse obj_cgroup APIs to charge the kmem pages, we should pass PAGE_SIZE (as third parameter) to obj_cgroup_charge(). Because the size is already PAGE_SIZE, we can skip touch the objcg stock. And obj_cgroup_{un}charge_pages() are introduced to charge in units of page level. In the latter patch, we also can reuse those two helpers to charge or uncharge a number of kernel pages to a object cgroup. This is just a code movement without any functional changes. Link: https://lkml.kernel.org/r/20210319163821.20704-3-songmuchun@bytedance.com Signed-off-by: Muchun Song Acked-by: Roman Gushchin Acked-by: Johannes Weiner Reviewed-by: Shakeel Butt Cc: Michal Hocko Cc: Vladimir Davydov Cc: Xiongchun Duan Signed-off-by: Andrew Morton --- mm/memcontrol.c | 63 +++++++++++++++++++++++++++++----------------- 1 file changed, 40 insertions(+), 23 deletions(-) --- a/mm/memcontrol.c~mm-memcontrol-introduce-obj_cgroup_uncharge_pages +++ a/mm/memcontrol.c @@ -2874,6 +2874,20 @@ static void commit_charge(struct page *p page->memcg_data = (unsigned long)memcg; } +static struct mem_cgroup *get_mem_cgroup_from_objcg(struct obj_cgroup *objcg) +{ + struct mem_cgroup *memcg; + + rcu_read_lock(); +retry: + memcg = obj_cgroup_memcg(objcg); + if (unlikely(!css_tryget(&memcg->css))) + goto retry; + rcu_read_unlock(); + + return memcg; +} + #ifdef CONFIG_MEMCG_KMEM int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s, gfp_t gfp, bool new_page) @@ -3025,6 +3039,29 @@ static void memcg_free_cache_id(int id) ida_simple_remove(&memcg_cache_ida, id); } +static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, + unsigned int nr_pages) +{ + struct mem_cgroup *memcg; + + memcg = get_mem_cgroup_from_objcg(objcg); + __memcg_kmem_uncharge(memcg, nr_pages); + css_put(&memcg->css); +} + +static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, + unsigned int nr_pages) +{ + struct mem_cgroup *memcg; + int ret; + + memcg = get_mem_cgroup_from_objcg(objcg); + ret = __memcg_kmem_charge(memcg, gfp, nr_pages); + css_put(&memcg->css); + + return ret; +} + /** * __memcg_kmem_charge: charge a number of kernel pages to a memcg * @memcg: memory cgroup to charge @@ -3149,19 +3186,8 @@ static void drain_obj_stock(struct memcg unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; unsigned int nr_bytes = stock->nr_bytes & (PAGE_SIZE - 1); - if (nr_pages) { - struct mem_cgroup *memcg; - - rcu_read_lock(); -retry: - memcg = obj_cgroup_memcg(old); - if (unlikely(!css_tryget(&memcg->css))) - goto retry; - rcu_read_unlock(); - - __memcg_kmem_uncharge(memcg, nr_pages); - css_put(&memcg->css); - } + if (nr_pages) + obj_cgroup_uncharge_pages(old, nr_pages); /* * The leftover is flushed to the centralized per-memcg value. @@ -3219,7 +3245,6 @@ static void refill_obj_stock(struct obj_ int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) { - struct mem_cgroup *memcg; unsigned int nr_pages, nr_bytes; int ret; @@ -3236,24 +3261,16 @@ int obj_cgroup_charge(struct obj_cgroup * refill_obj_stock(), called from this function or * independently later. */ - rcu_read_lock(); -retry: - memcg = obj_cgroup_memcg(objcg); - if (unlikely(!css_tryget(&memcg->css))) - goto retry; - rcu_read_unlock(); - nr_pages = size >> PAGE_SHIFT; nr_bytes = size & (PAGE_SIZE - 1); if (nr_bytes) nr_pages += 1; - ret = __memcg_kmem_charge(memcg, gfp, nr_pages); + ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); if (!ret && nr_bytes) refill_obj_stock(objcg, PAGE_SIZE - nr_bytes); - css_put(&memcg->css); return ret; } _