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]) by smtp.lore.kernel.org (Postfix) with ESMTP id D171DC636F0 for ; Wed, 28 Aug 2024 17:49:35 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 30A256B0092; Wed, 28 Aug 2024 13:49:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 290B66B0093; Wed, 28 Aug 2024 13:49:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 10C3A6B0095; Wed, 28 Aug 2024 13:49:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id E4EA36B0092 for ; Wed, 28 Aug 2024 13:49:34 -0400 (EDT) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id AD94016051B for ; Wed, 28 Aug 2024 17:49:34 +0000 (UTC) X-FDA: 82502391468.03.6E60DBA Received: from mail-qt1-f177.google.com (mail-qt1-f177.google.com [209.85.160.177]) by imf19.hostedemail.com (Postfix) with ESMTP id E8D0D1A0004 for ; Wed, 28 Aug 2024 17:49:32 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=dTZ62Bqx; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf19.hostedemail.com: domain of tjmercier@google.com designates 209.85.160.177 as permitted sender) smtp.mailfrom=tjmercier@google.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1724867308; a=rsa-sha256; cv=none; b=Cvq8xUBouZ5cRBpexUj47UoP85PVoI7M7oghW8nlkZf0DceacAShBIo3i/ht4FP6xJXYUp 4yZnF9bquT6D3YSGRSnHPr46QBC1Mg5FA2i7jbx+Rw2ra25nJivjJzHxH1priUMf+FbzTe ddlrR77yaUixO7cYO0iCaRwEoE/L/A8= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=dTZ62Bqx; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf19.hostedemail.com: domain of tjmercier@google.com designates 209.85.160.177 as permitted sender) smtp.mailfrom=tjmercier@google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1724867307; 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=aDE3/DKrfhnHsPGNKsCJRM7x+xvPEnRxpqQ1AnnBWEM=; b=G+fBKgfE5OFY4cuUhEXM+uddk5bVt+pTn/j9Yo3RzLInk06QAljfeLhZGY5AhhDU+w9w6d cG51Vo4BK85OKqtLGh/pIeIfrLlNC5TooyVMK5EnMN87vpbH0wtBBKn8IpY2f8BhzVfpIN piJpirSYefhtTj3EK+glfKRX5StKaww= Received: by mail-qt1-f177.google.com with SMTP id d75a77b69052e-4567deb9f9dso20361cf.1 for ; Wed, 28 Aug 2024 10:49:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1724867372; x=1725472172; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=aDE3/DKrfhnHsPGNKsCJRM7x+xvPEnRxpqQ1AnnBWEM=; b=dTZ62BqxQeEZh5I8p1jXhfZGP8x9CACPS4T1ghM9lncx3yCCAcOIiZClzooB9g/Dwo e1kioo5NzupI/1INAnu7unsNOenC60ljAbD4aq+RH1Z+P8rc0SOggkcsepTnLIF8OD5L 77qT2dgI3iiuY/31cDcdNOgawUNGre0XYQqPGZorBuup2Lx3ivYmkeVW/ODn1wW79foP VtF+Zb6j/CtdnbaBkvs8KdRk7eD3bUd9iACv06adh5sFgj9KT66ytfLLF4iTD8Ep5CtQ NRETOkoIm24yQq8bTCsEPV6YM5yiv3uXV5GqtJ1SsZ1ZMPb7pafJdyxVG3C9lI5uTo3o uaCg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724867372; x=1725472172; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aDE3/DKrfhnHsPGNKsCJRM7x+xvPEnRxpqQ1AnnBWEM=; b=VwQkBCffBx1wPYSxovBCwnUTR+nYVxh4g5DmXGkgGZg2DoPSyanEf6BV8GrcEXKOg4 T4U3i69vJStZj3NGE6wSg0SgVEOCLr+UzTnkC2woB8ifjNEXnq+9B5pw5Cd52TQlp7sn rEVh3FxJDib1VSujvr0OnfbKFtUUrbU4NBahmuaCRTtF+0fVxqg2LbXK8k8ELnAIfkHk ASkhNhzaZVnYPYsqTyZIIniJ+ZdrsfKaJJpdL9GmE8lQGkWAL+GGQJQUl9GkXVz9Y1Ih HGQibJSq2nXXu8nPBtiNbXJl3dPs0/Dt3h/cb5XM/cd/VHpFYuqpt2rwXBmpe7c6UDTF wiRw== X-Forwarded-Encrypted: i=1; AJvYcCUaIbctHD8JB3nHzHw3Pydk2n/fouBU1ukidwZbVBj/f/QZj/0Rnzfrol8Fm9+Pf5OhgHH5BgydtA==@kvack.org X-Gm-Message-State: AOJu0Yz5Ge95QkCOQEOWTYsPmIdolSkW/a3m/yg/p/mgfpSg3dcvVzeB knCS3Oy9fK+nPf3wwhvbQg+bb3Z/Mj9LRsX8pFW056MnDETWSLgN0oFwbf2UlwagcV9Q9b0Vf3+ dPBjd4tzzB4Lq9F+/hqCVvLJUY3+8v2DmiifC X-Google-Smtp-Source: AGHT+IG4aL6108P6ITzETjngxN9DfIkjrJd7iPcDgQ+blSAFzi8AqbC0n0lCxGYQ4Dl+bUU1WJUlKUcFIvJPftTyGXg= X-Received: by 2002:ac8:7d4c:0:b0:453:5668:444e with SMTP id d75a77b69052e-4567fbbbc61mr100361cf.2.1724867371883; Wed, 28 Aug 2024 10:49:31 -0700 (PDT) MIME-Version: 1.0 References: <20240827230753.2073580-1-kinseyho@google.com> <20240827230753.2073580-5-kinseyho@google.com> In-Reply-To: <20240827230753.2073580-5-kinseyho@google.com> From: "T.J. Mercier" Date: Wed, 28 Aug 2024 10:49:20 -0700 Message-ID: Subject: Re: [PATCH mm-unstable v3 4/5] mm: restart if multiple traversals raced To: Kinsey Ho Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Yosry Ahmed , Roman Gushchin , Johannes Weiner , Michal Hocko , Shakeel Butt , Muchun Song , Tejun Heo , Zefan Li , mkoutny@suse.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: E8D0D1A0004 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 3umrqooxyfp85ht9q3pzp7tjibsrgxqi X-HE-Tag: 1724867372-522443 X-HE-Meta: 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 eG8te7qA oVvHsbbfFQlU84pRfPu2uRetGCJ7cO8UK+0r2LbhcSHRuPMpfVUtA25dYAi4HjBfP/8/4XwXGQAWK5fVu/OVlWT7+K8JdOTCWBXe1Mz3iZhi7UMNhZUjRa3m63MCxX1zhtlO2UQ0SDojjjBAlXpDIm4t9e1pTn1g+ArpSOhpPznJ41WpQCnpdecOn5YVbHDEj98Bim9DRn0v72CWfKHptfnNLVM0uZDzEpj9o X-Bogosity: Ham, tests=bogofilter, spamicity=0.001386, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Aug 27, 2024 at 4:11=E2=80=AFPM Kinsey Ho wro= te: > > Currently, if multiple reclaimers raced on the same position, the > reclaimers which detect the race will still reclaim from the same memcg. > Instead, the reclaimers which detect the race should move on to the next > memcg in the hierarchy. > > So, in the case where multiple traversals race, jump back to the start > of the mem_cgroup_iter() function to find the next memcg in the > hierarchy to reclaim from. > > Signed-off-by: Kinsey Ho Reviewed-by: T.J. Mercier