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 28EA2C5B572 for ; Tue, 18 Aug 2026 01:05:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 254D06B0886; Mon, 17 Aug 2026 21:05:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 22C2F6B088C; Mon, 17 Aug 2026 21:05:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 16BE86B0892; Mon, 17 Aug 2026 21:05:30 -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 DF37B6B0886 for ; Mon, 17 Aug 2026 21:05:29 -0400 (EDT) Received: from smtpin08.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 65CEAA362C for ; Tue, 18 Aug 2026 01:05:29 +0000 (UTC) X-FDA: 85112597178.08.26755BC Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) by imf05.hostedemail.com (Postfix) with ESMTP id 2642D100007 for ; Tue, 18 Aug 2026 01:05:25 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; spf=pass (imf05.hostedemail.com: domain of husong@kylinos.cn designates 124.126.103.232 as permitted sender) smtp.mailfrom=husong@kylinos.cn ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1787015127; b=S3zrRqdFyv7B+AvkeZ1grjgBI2Pd7dNFy8ucEV/FC0VpOi0fWKPdZBsieObkP0rDX5NlTi z/zyQky1G9jIj5rzQyEOspG+BEpKNC2ZMoUW3T81uRqfMh1ocdqbBrZaL4xfWYDer6xq70 nebABHf8BAza/3IRQhud+cPojzQjdmY= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf05.hostedemail.com: domain of husong@kylinos.cn designates 124.126.103.232 as permitted sender) smtp.mailfrom=husong@kylinos.cn ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1787015127; 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; bh=ldI2PA8PHpJFTuUK5RjS+4cmA6h1TKoHDrn5lMVtpIY=; b=OEwgQkg0GHsCzqEYyeEeIo61KTKDH+Kp7/a9CGzwYdyP1B9jGUppNOUXT+gnQSCEp31CYB kCwJtQXY+8Bp1zs0ZlIGxjMrHzHmIDBtFvH4ztFkJRZyf7LyljE33JZn92J7XhgGVYmjkh OO13PVKMN30MdRPpnH4fBlaxAx/LxDQ= X-UUID: de1bf62c9aa011f19a56ed5b684f684d-20260818 X-CTIC-Tags: HR_CC_COUNT, HR_CC_DOMAIN_COUNT, HR_CC_NO_NAME, HR_CTE_8B, HR_CTT_MISS HR_DATE_H, HR_DATE_WKD, HR_DATE_ZONE, HR_FROM_NAME, HR_SJ_DIGIT_LEN HR_SJ_LANG, HR_SJ_LEN, HR_SJ_LETTER, HR_SJ_NOR_SYM, HR_SJ_PHRASE HR_SJ_PHRASE_LEN, HR_SJ_PRE_RE, HR_SJ_WS, HR_TO_COUNT, HR_TO_DOMAIN_COUNT HR_TO_NO_NAME, IP_TRUSTED, SRC_TRUSTED, DN_TRUSTED, SA_TRUSTED SA_EXISTED, SN_TRUSTED, SN_EXISTED, SPF_NOPASS, DKIM_NOPASS DMARC_NOPASS, CIE_GOOD, CIE_GOOD_SPF, GTI_FG_BS, GTI_RG_INFO GTI_C_BU, AMN_GOOD, ABX_MISS_RDNS X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.19,REQID:67336774-f8da-4d01-b25d-312dbc6da10a,IP:10, URL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:10 X-CID-INFO: VERSION:1.3.19,REQID:67336774-f8da-4d01-b25d-312dbc6da10a,IP:10,UR L:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION:r elease,TS:10 X-CID-META: VersionHash:7db8b62,CLOUDID:2426a112fd7eed1304d354514c774d3a,BulkI D:260811205833BZBX3QXG,BulkQuantity:1,SF:17|19|64|66|78|80|81|82|83|102|12 7|841|865|898,TC:nil,Content:0|15|50,EDM:-3,IP:-2,URL:0,File:nil,RT:nil,Bu lk:40,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0 ,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_FAS,TF_CID_SPAM_FSD X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: de1bf62c9aa011f19a56ed5b684f684d-20260818 X-User: husong@kylinos.cn Received: from ctao-book.. [(223.70.159.239)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1340971763; Tue, 18 Aug 2026 09:05:13 +0800 From: Song Hu To: ye.liu@linux.dev Cc: akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, liuye@kylinos.cn, mhocko@suse.com, rientjes@google.com, shakeel.butt@linux.dev, husong@kylinos.cn Subject: Re: [PATCH] mm/oom_kill, proc: replace magic number 1000 with OOM_SCORE_ADJ_MAX Date: Tue, 18 Aug 2026 09:04:33 +0800 Message-ID: <20260818010433.65169-1-husong@kylinos.cn> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260811033609.3992348-1-ye.liu@linux.dev> References: <20260811033609.3992348-1-ye.liu@linux.dev> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 2642D100007 X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: 8ocoznjw1f1zojtzuxu93ktz4dp9priw X-HE-Tag: 1787015125-823307 X-HE-Meta: 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 QK8GC1JO TQkzdIYdvBcRMa1n67sCqZu9pdTOXiXJ/jvGVIvE+/vDX6S8= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2026/8/11 11:36, Ye Liu wrote: > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -230,7 +230,7 @@ long oom_badness(struct task_struct *p, unsigned long totalpages) > task_unlock(p); > > /* Normalize to oom_score_adj units */ > - adj *= totalpages / 1000; > + adj *= totalpages / OOM_SCORE_ADJ_MAX; One thing this line hides: for a memcg OOM, totalpages is mem_cgroup_get_max(), which can be below 1000 pages when the container limit is under 4M. The division then yields 0, the whole oom_score_adj contribution goes away, and a task protected with -997 scores the same as a best-effort task with 1000. The -1000 exemption is checked separately above and still works. DIV_ROUND_UP(totalpages, OOM_SCORE_ADJ_MAX) would preserve the adj weighting for small limits and change nothing meaningful for large ones. This is an edge case, so probably fine to leave as is - noting it here since the line is being touched anyway.