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 588A6FB5181 for ; Tue, 7 Apr 2026 02:13:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 845A66B0088; Mon, 6 Apr 2026 22:13:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7F7016B0089; Mon, 6 Apr 2026 22:13:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 70C326B008A; Mon, 6 Apr 2026 22:13:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 6094E6B0088 for ; Mon, 6 Apr 2026 22:13:12 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 01E331A0598 for ; Tue, 7 Apr 2026 02:13:11 +0000 (UTC) X-FDA: 84630137424.11.DEF9BF2 Received: from out-180.mta1.migadu.com (out-180.mta1.migadu.com [95.215.58.180]) by imf07.hostedemail.com (Postfix) with ESMTP id 25D0E4000B for ; Tue, 7 Apr 2026 02:13:09 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=p7s78Uy1; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf07.hostedemail.com: domain of qi.zheng@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1775527990; a=rsa-sha256; cv=none; b=c4ZDcbRyMytkd9fhKb7b3/gpq8pl1sGF2/mZFZX5zWI58j8sxHmuuWbfrBqOyRVjCylzUB QZk4+aIQN03ptKtnzHmA82iab9B3g91Z0+Bk1kBa+XJUU9bLV1AcmDtxOjrdy/pq0TInJw /DOisSncufdkrbKFAPfuycs+aYvSujQ= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=p7s78Uy1; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf07.hostedemail.com: domain of qi.zheng@linux.dev designates 95.215.58.180 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1775527990; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=PSDM3Xa9OKTpOqUyJXXJL/N9oKWp7CgjmMDNFGNadDU=; b=z/H+VVw73tCDjqt+PU728tJOOzkiigPCLQfBdiVB7fQK05/6RBK4UnfB9odRzRTCDu1ovW IXTNKacXoaeECDh0BmXePc0SVG76PU9hacEUynsH6XZnLoLqgvzlHC91ygXj4PAaG90NxT SCvXkuduwxMtuZ5lKmPOBif2N9Qh/Uc= Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1775527986; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PSDM3Xa9OKTpOqUyJXXJL/N9oKWp7CgjmMDNFGNadDU=; b=p7s78Uy1xvl6dGGM0H/S2+3LMU53v9/HniExRR/oiOtc7e6yjcBCt4BY01g7CRLXeb2hVg zDYw4oa6DyVw23A/EnX5JQIwIHy66z+3poLCY2j74zgp0p/h3vc+2kxmDji382FVGeEmpO 8CGpM6DUnj+5UagK8/p3VNxy1WNSsMQ= Date: Tue, 7 Apr 2026 10:12:30 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v6 32/33] mm: memcontrol: eliminate the problem of dying memory cgroup for LRU folios To: Joshua Hahn Cc: 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, linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Muchun Song , Qi Zheng References: <20260406181116.4053796-1-joshua.hahnjy@gmail.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <20260406181116.4053796-1-joshua.hahnjy@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Stat-Signature: sbnkkce54uwm1jb7hs9epybeny14khe3 X-Rspamd-Queue-Id: 25D0E4000B X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1775527989-580127 X-HE-Meta: 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 BOnMZ4R7 8nuyxR2uXxVprrhExquBzLwix9HNt6eOFUNyLoo4WBtKMmFEyFsQBR/rYGFq+8ZhxWbZubKBZtWI5qmaJzHTOOiXeCGDfQdmi2cMaCVmG1JQj3HNuA+0hcwXgGGi84D/oeu39zkue9nJvFWDNVsPG/cVsq+aYuBhod4KqWYQRpZi3hDYCPkt/Jha8pj6mWiW60AQsuYFxC+Jf6tWwP5XSZzt0TIcwi54F1028A7aXQK9cifr6sJGLYoyWHWZx4DWqIRzR9By2jNMIgqU6oH13taG9ks/5EweoReZAYEP0MHJhAYf6VRaVZMNKsClMiDsSbZLQvCNXwZD6iMMRVV8LWnIiQw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/7/26 2:11 AM, Joshua Hahn wrote: > On Thu, 5 Mar 2026 19:52:50 +0800 Qi Zheng wrote: > >> From: Muchun Song >> >> Now that everything is set up, switch folio->memcg_data pointers to >> objcgs, update the accessors, and execute reparenting on cgroup death. >> >> Finally, folio->memcg_data of LRU folios and kmem folios will always >> point to an object cgroup pointer. The folio->memcg_data of slab >> folios will point to an vector of object cgroups. >> >> Signed-off-by: Muchun Song >> Signed-off-by: Qi Zheng >> Acked-by: Shakeel Butt >> --- > > Hello Qi, thank you for this series! > >> static void memcg_online_kmem(struct mem_cgroup *memcg) >> @@ -4949,16 +4985,20 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root, >> static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, >> gfp_t gfp) >> { >> - int ret; >> - >> - ret = try_charge(memcg, gfp, folio_nr_pages(folio)); > > While developing on top of mm-new I found that this was the last caller of > try_charge(). I was thinking that it might be a nice opportunity to just Yeah, we're already aware of this. > remove the definition of try_charge() as well, maybe as a clean up patch > at the end of the series. Will send a separate cleanup patch later. Thanks, Qi