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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6B32AF30950 for ; Thu, 5 Mar 2026 11:59:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D5A4B6B00C5; Thu, 5 Mar 2026 06:59:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id D04E36B00C7; Thu, 5 Mar 2026 06:59:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BF3116B00C8; Thu, 5 Mar 2026 06:59:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id AB2E26B00C5 for ; Thu, 5 Mar 2026 06:59:00 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 7447B13BE66 for ; Thu, 5 Mar 2026 11:59:00 +0000 (UTC) X-FDA: 84511863240.07.02167E8 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) by imf17.hostedemail.com (Postfix) with ESMTP id C5AD240006 for ; Thu, 5 Mar 2026 11:58:58 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=BOcfMfGt; spf=pass (imf17.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.172 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1772711939; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Ih1p6IEUWMwvOImSKCL1YcoSFVupYh3GoMOZwrQGBdQ=; b=0vgmaylwjjlOP+smAIX3KuOi6AYmvhmq1QEh4tGqEuTOh11fwHvPWxQfZDkCgvWRBc2kUL JsEQCW42vb5j9QRt6tL0JneL0hKCRUyaEeQlISVMDS5O7QlhYzVOV0/5fTpQ1Lb1QBUg6h QQAj2szMLbVDFNgf86rN9TishAdOfJs= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=BOcfMfGt; spf=pass (imf17.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.172 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772711939; a=rsa-sha256; cv=none; b=Ejlye74y7Ep56Sm+h8iCnmxr36CcAkcXMBge6YhwcGc9OtaYVf/SVPuftfz4LRGxzXkLtC IzJfxDdUs0P2G6RAVQLlMe2t3MNp3gpLE1FI0Affgk/VN+AJIE6/8brULTbGjDv/QUUIKw uG3HNmYkmQYsDd1x0fvuQ10IPTm0BlM= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1772711937; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Ih1p6IEUWMwvOImSKCL1YcoSFVupYh3GoMOZwrQGBdQ=; b=BOcfMfGtjpHcZp+xS/IpT3JULkLv02uZSYMCkCq8bDAyt4Jvy92uC0aTckuxqn3xx3Jxbb q/M0pn2SWVc7gCp+kU8JZd+USDTs48XoIopK3xpPraNBcil60WNqxgue3ZE0S/NnoqLuR+ zXFJzorToXtaCX16OVcQD6Gtc39QfHA= From: Qi Zheng To: hannes@cmpxchg.org, hughd@google.com, mhocko@suse.com, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, david@kernel.org, lorenzo.stoakes@oracle.com, ziy@nvidia.com, harry.yoo@oracle.com, yosry.ahmed@linux.dev, imran.f.khan@oracle.com, kamalesh.babulal@oracle.com, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chenridong@huaweicloud.com, mkoutny@suse.com, akpm@linux-foundation.org, hamzamahfooz@linux.microsoft.com, apais@linux.microsoft.com, lance.yang@linux.dev, bhe@redhat.com, usamaarif642@gmail.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Qi Zheng Subject: [PATCH v6 27/33] mm: memcontrol: refactor memcg_reparent_objcgs() Date: Thu, 5 Mar 2026 19:52:45 +0800 Message-ID: <2e5696db1993e593a51004c1dacedbc261689629.1772711148.git.zhengqi.arch@bytedance.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: C5AD240006 X-Rspamd-Server: rspam07 X-Stat-Signature: djhdfoi9e366zfisgx1neb5h49z4igop X-Rspam-User: X-HE-Tag: 1772711938-323125 X-HE-Meta: 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 QttrN5pQ dfRFmSLUcqvxQekCU1SIZKRY6CE7Mudyi8ucUdAV2hd3gmSUw6ImomLE9c7q9NW1ahcJDaNVRPwPnFXKCgsS4Bu+GCBcmF3ljjiHDP2HdZdzN4HVM8o/tknA9WtY2Fhnj2ZU3QhjGcQzneu2seIHzeMdjH8zFHB1sUtPom7bCnklsp0gJGKiqu0bQBO56KumcIJOZhoLxIBGfS2RImyizTxjHyqjw65kG71SGG3fJaqUXFlLBLZgs4AZyEQ1kn3pEJELw4bJ97/KdsAu3sm+9ghUPEzZUBySk9hOJn6u/fNidJ87+Wjuz5C/oGJYMmTEMuwa0B/k/TF8hv8X26FsTGR64var6XokaZnwK Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Qi Zheng Refactor the memcg_reparent_objcgs() to facilitate subsequent reparenting LRU folios here. Signed-off-by: Qi Zheng Acked-by: Johannes Weiner Acked-by: Shakeel Butt Reviewed-by: Harry Yoo Reviewed-by: Muchun Song --- mm/memcontrol.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 49a076b7c2e42..5929e397c3c31 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -209,15 +209,12 @@ static struct obj_cgroup *obj_cgroup_alloc(void) return objcg; } -static void memcg_reparent_objcgs(struct mem_cgroup *memcg) +static inline struct obj_cgroup *__memcg_reparent_objcgs(struct mem_cgroup *memcg, + struct mem_cgroup *parent) { struct obj_cgroup *objcg, *iter; - struct mem_cgroup *parent = parent_mem_cgroup(memcg); objcg = rcu_replace_pointer(memcg->objcg, NULL, true); - - spin_lock_irq(&objcg_lock); - /* 1) Ready to reparent active objcg. */ list_add(&objcg->list, &memcg->objcg_list); /* 2) Reparent active objcg and already reparented objcgs to parent. */ @@ -226,7 +223,29 @@ static void memcg_reparent_objcgs(struct mem_cgroup *memcg) /* 3) Move already reparented objcgs to the parent's list */ list_splice(&memcg->objcg_list, &parent->objcg_list); + return objcg; +} + +static inline void reparent_locks(struct mem_cgroup *memcg, struct mem_cgroup *parent) +{ + spin_lock_irq(&objcg_lock); +} + +static inline void reparent_unlocks(struct mem_cgroup *memcg, struct mem_cgroup *parent) +{ spin_unlock_irq(&objcg_lock); +} + +static void memcg_reparent_objcgs(struct mem_cgroup *memcg) +{ + struct obj_cgroup *objcg; + struct mem_cgroup *parent = parent_mem_cgroup(memcg); + + reparent_locks(memcg, parent); + + objcg = __memcg_reparent_objcgs(memcg, parent); + + reparent_unlocks(memcg, parent); percpu_ref_kill(&objcg->refcnt); } -- 2.20.1