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 C6374C48BC4 for ; Fri, 23 Feb 2024 03:46:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A68036B0072; Thu, 22 Feb 2024 22:46:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A189B6B0074; Thu, 22 Feb 2024 22:46:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8DF896B0075; Thu, 22 Feb 2024 22:46:03 -0500 (EST) 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 7F00F6B0072 for ; Thu, 22 Feb 2024 22:46:03 -0500 (EST) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 7E8A7C1072 for ; Fri, 23 Feb 2024 03:37:09 +0000 (UTC) X-FDA: 81821657778.21.CD0DD44 Received: from out-187.mta0.migadu.com (out-187.mta0.migadu.com [91.218.175.187]) by imf29.hostedemail.com (Postfix) with ESMTP id 6F59712001C for ; Fri, 23 Feb 2024 03:37:02 +0000 (UTC) Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ce5CfSyh; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf29.hostedemail.com: domain of chengming.zhou@linux.dev designates 91.218.175.187 as permitted sender) smtp.mailfrom=chengming.zhou@linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1708659422; 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=SL5JDmsyHyQirdU0lRKG6MlAN0ZaRI5cpkmSUjlEF9M=; b=J/mMtu63N1oFyJkF4+02tuR0KUepWluXINKvWs3elLfugCSMlJ9t0KArMRrmZ5xtLANER/ aSkE9gY9pNTV5deT7MjZJW8Llncy2o3SOK8mTRD2lB8yusXj2gnIBO+5ZyqHhMtdEVqI1G Ht5eupk6H3nVOjjc8TeSy/YbZEyPdHA= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=ce5CfSyh; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf29.hostedemail.com: domain of chengming.zhou@linux.dev designates 91.218.175.187 as permitted sender) smtp.mailfrom=chengming.zhou@linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1708659422; a=rsa-sha256; cv=none; b=mpEgErfCuj1F9MF2olFZ5jxT0c3n8JPGtFr82yinbV0WI4ylnkzUvHgBY+ogTelpuiprXZ 9NrTl6aHIz5zRHJuks/CxO69ZLG453aHZW/taTNsYE/+tQoxceeybWZWHVD5RgXtat2gXe HiqyEaWlb+r3SzDEUS9Fz8bVlfJLe6o= Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1708659420; 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=SL5JDmsyHyQirdU0lRKG6MlAN0ZaRI5cpkmSUjlEF9M=; b=ce5CfSyh0SuptVAvN/p/KYapS0NjlEJIZQuvwyUi33/REvbxv9IvkFjf26cFvC9uMD4FtP X3kiweqSqGZmYzeOXNdDDCznzB8TTo36TpgCXQqgqaKDy3dys1b3ljzkWsEleBIH1PB1rX koWEP+tu1VBfCBrrYq4+lGoWWembyoY= Date: Fri, 23 Feb 2024 11:36:25 +0800 MIME-Version: 1.0 Subject: Re: [PATCH] slub: avoid scanning all partial slabs in get_slabinfo() Content-Language: en-US To: "Christoph Lameter (Ampere)" Cc: Vlastimil Babka , David Rientjes , Jianfeng Wang , penberg@kernel.org, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chengming Zhou References: <20240215211457.32172-1-jianfeng.w.wang@oracle.com> <6b58d81f-8e8f-3732-a5d4-40eece75013b@google.com> <55ccc92a-79fa-42d2-97d8-b514cf00823b@linux.dev> <6daf88a2-84c2-5ba4-853c-c38cca4a03cb@linux.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Chengming Zhou In-Reply-To: <6daf88a2-84c2-5ba4-853c-c38cca4a03cb@linux.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 6F59712001C X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: y4qdpzru4zypyxo7pzoebwk4ba3546bh X-HE-Tag: 1708659422-630149 X-HE-Meta: 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 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: List-Subscribe: List-Unsubscribe: On 2024/2/23 11:02, Christoph Lameter (Ampere) wrote: > On Thu, 22 Feb 2024, Chengming Zhou wrote: > >> Anyway, I put the code below for discussion... > > Can we guestimate the free objects based on the number of partial slabs. That number is available. > Yeah, the number of partial slabs is easy to know, but I can't think of a way to estimate the free objects, since __slab_free() is just double cmpxchg in most cases. > How accurate need the accounting be? We also have fuzzy accounting in the VM counters. Maybe not need to be very accurate, some delay/fuzzy should be acceptable. Another direction I think is that we don't distinguish slabs on cpu partial list or slabs on node partial list anymore (different with current behavior). Now we have three scopes: 1. SL_ALL: include all slabs 2. SL_PARTIAL: only include partial slabs on node 3. SL_CPU: only include partail slabs on cpu and the using cpu slab If we change SL_PARTIAL to mean all partial slabs, it maybe simpler. Thanks.