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 51CC6C28D13 for ; Mon, 22 Aug 2022 22:48:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AAAAB6B0073; Mon, 22 Aug 2022 18:48:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A59636B0074; Mon, 22 Aug 2022 18:48:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8FB3B6B0075; Mon, 22 Aug 2022 18:48:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 811276B0073 for ; Mon, 22 Aug 2022 18:48:27 -0400 (EDT) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 539C71C6516 for ; Mon, 22 Aug 2022 22:48:27 +0000 (UTC) X-FDA: 79828719054.14.D76F4BE Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf12.hostedemail.com (Postfix) with ESMTP id EE16F40002 for ; Mon, 22 Aug 2022 22:48:26 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6F64FB8125E; Mon, 22 Aug 2022 22:48:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F577C433C1; Mon, 22 Aug 2022 22:48:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1661208504; bh=sOMr0Q0H2AG8pe61BiyqwV9Vfzg1HO+X+80PtuoQ1U4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=jn+jIXL11peml5c/5m7jlSUZ/Nprd5dtsyObenqGyKRa1wB5SSgUh7saBlD6qhEZe 9dJ14IaEgzUssPm8IZCRYaCjc1FsFDWBZwyNVH5MvGu79dGwsSc9QQF/kdJiMsNDtG 1z9khI42mLkZ4hQjcdvU87pTUkDIxriT5nyO/uMY= Date: Mon, 22 Aug 2022 15:48:22 -0700 From: Andrew Morton To: Yu Zhao Cc: Suren Baghdasaryan , Michal Hocko , David Rientjes , Matthew Wilcox , Johannes Weiner , Roman Gushchin , Minchan Kim , "Kirill A . Shutemov" , Andrea Arcangeli , brauner@kernel.org, hch@infradead.org, oleg@redhat.com, David Hildenbrand , Jann Horn , Shakeel Butt , Peter Xu , John Hubbard , shuah@kernel.org, linux-kernel , Linux-MM , linux-kselftest@vger.kernel.org, kernel-team@android.com Subject: Re: [PATCH RESEND v2 2/2] mm: delete unused MMF_OOM_VICTIM flag Message-Id: <20220822154822.366a9e4527b748cf99d98637@linux-foundation.org> In-Reply-To: References: <20220531223100.510392-1-surenb@google.com> <20220531223100.510392-2-surenb@google.com> <20220822152119.96d40c884078229ee3e6b25e@linux-foundation.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661208507; 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=ckxQ+Utm/POheRNKJE9phiXwT6cy3rflKY1WK3/z0dQ=; b=sKfXWLXOAf3kerjO6WuAZLjNYobMt/Fv4BaUh9r4ENA7+3BkI6/yzUcCaU1N8Cam9TS7nx QCCxN0SSiB6Y2LtfRfMp/oPf63sgdDmJvby/4lQ6ZKJQPn0Yxfqd16i6ziD1fAePJjdVvj 8GkcmsH9NJXXhsOdtAKyeBosYjoPmxQ= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=jn+jIXL1; spf=pass (imf12.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661208507; a=rsa-sha256; cv=none; b=QE6xIbfOX3nG3Ok/WltadMiqfUDOlnYRD06qd+N57/nKMeI034Bka5atAt+QA1wxPa6Jfn T6KQdEdN0cAO2MxIRiCwPPriEVdeWBpmUEPAmojacrqi7Hsa52i1ZRaEKLWH17ydVH5do7 mlAGEKGQF+YePTro+OsrKvSQpKX24ao= X-Stat-Signature: wra7g7ypue7dfzdkn5jtjkdcoexhjm6j Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=jn+jIXL1; spf=pass (imf12.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: EE16F40002 X-Rspam-User: X-HE-Tag: 1661208506-118551 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, 22 Aug 2022 16:33:51 -0600 Yu Zhao wrote: > > --- a/mm/vmscan.c~mm-delete-unused-mmf_oom_victim-flag-fix > > +++ a/mm/vmscan.c > > @@ -3429,9 +3429,6 @@ static bool should_skip_mm(struct mm_str > > if (size < MIN_LRU_BATCH) > > return true; > > > > - if (mm_is_oom_victim(mm)) > > - return true; > > - > > return !mmget_not_zero(mm); > > } > > > > @@ -4127,9 +4124,6 @@ restart: > > > > walk_pmd_range(&val, addr, next, args); > > > > - if (mm_is_oom_victim(args->mm)) > > - return 1; > > - > > /* a racy check to curtail the waiting time */ > > if (wq_has_sleeper(&walk->lruvec->mm_state.wait)) > > return 1; > > _ > > > > Please confirm? > > LGTM. The deleted checks are not about correctness. OK, for now. > I've queued > > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -3402,7 +3402,7 @@ static bool should_skip_mm(struct mm_struct *mm, > struct lru_gen_mm_walk *walk) > if (size < MIN_LRU_BATCH) > return true; > > - if (mm_is_oom_victim(mm)) > + if (test_bit(MMF_OOM_REAP_QUEUED, &mm->flags)) > return true; > > return !mmget_not_zero(mm); > @@ -4109,7 +4109,7 @@ static int walk_pud_range(p4d_t *p4d, unsigned > long start, unsigned long end, > > walk_pmd_range(&val, addr, next, args); > > - if (mm_is_oom_victim(args->mm)) > + if (test_bit(MMF_OOM_REAP_QUEUED, &args->mm->flags)) > return 1; > > /* a racy check to curtail the waiting time */ Oh. Why? What does this change do?