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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2D04C76196 for ; Tue, 28 Mar 2023 16:55:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231582AbjC1Qz6 (ORCPT ); Tue, 28 Mar 2023 12:55:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230384AbjC1Qz5 (ORCPT ); Tue, 28 Mar 2023 12:55:57 -0400 Received: from out-13.mta1.migadu.com (out-13.mta1.migadu.com [95.215.58.13]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39C83B746 for ; Tue, 28 Mar 2023 09:55:56 -0700 (PDT) Date: Tue, 28 Mar 2023 12:55:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1680022554; 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: in-reply-to:in-reply-to:references:references; bh=hxBJnNBm/cNkHCZcwSILQF6wnG9ilV9aQydMGT1rWvc=; b=VkJqDZG+29d//8LLQh/wx5LDGNqIe/T2Z+MMrUsnWdQTtA3opKIdt/us+IYc7a1GHMTVQG cTx67DsHRe2UY5fIl8hBB9LNV0MF5SoMWxOhsPuEjr35k2K+zviAiWLCJ25s1q5Yv9gJmQ IlXq1BeUjhk4eys036gB7dm6q8f5GkM= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: Vlastimil Babka Cc: Suren Baghdasaryan , lsf-pc@lists.linux-foundation.org, linux-fsdevel , linux-mm Subject: Re: [LSF/MM/BPF TOPIC] Memory profiling using code tagging Message-ID: References: <115288f8-bd28-f01f-dd91-63015dcc635d@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <115288f8-bd28-f01f-dd91-63015dcc635d@suse.cz> X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Mar 28, 2023 at 06:28:21PM +0200, Vlastimil Babka wrote: > On 2/22/23 20:31, Suren Baghdasaryan wrote: > > We would like to continue the discussion about code tagging use for > > memory allocation profiling. The code tagging framework [1] and its > > applications were posted as an RFC [2] and discussed at LPC 2022. It > > has many applications proposed in the RFC but we would like to focus > > on its application for memory profiling. It can be used as a > > low-overhead solution to track memory leaks, rank memory consumers by > > the amount of memory they use, identify memory allocation hot paths > > and possible other use cases. > > Kent Overstreet and I worked on simplifying the solution, minimizing > > the overhead and implementing features requested during RFC review. > > IIRC one large objection was the use of page_ext, I don't recall if you > found another solution to that? No, page_ext is really the thing that makes the most sense here. It's per-page allocation information, so the only other place it could go is in struct page itself - but that doesn't make any sense with the boot time option we've got now, page_ext works perfectly with that.