From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DDCA83AB29C; Thu, 18 Jun 2026 12:38:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781786336; cv=none; b=o942DRMrVIEVMCIAdqLGILvqPtmLEeGIIlAGjb/cI2nBJw7QAe/UkRA+5mRtRxfZW1EFMAKQP4HfhaiUDE/d2qozQu8C9J5K0u9u2rcy+Z3guoRAyZGvzHMgGrKtJlMMkfc+wpf/plB9IJPLNkEfXoBbWnfGZI1FRVAWXz23PN8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781786336; c=relaxed/simple; bh=NKKv11XE0zF/nCIUid6G7GBfJ24lYlVE9oBD4P57fGs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=l/MYt3XK+k9pzw1Mq9cU9RssbNHsSj7LQQi3hLQ/PBLU4Vcy8VhkEp1wNsyc1ALpbgshHxzlOfLAUb5bSXr/6f3unV7aWa+N0xa+NAz/7PQnxAqSBD0aszq1R7d8JlmKllq3ViI8FnhMJgAzWw8G2B6dRDyo7o2GoxAnKIRQlfI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PXZvhX1w; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PXZvhX1w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 44C441F000E9; Thu, 18 Jun 2026 12:38:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781786335; bh=v5OV2563283YHAEvpvJhlyU83u7DJ+i27wFCKx2WtMc=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=PXZvhX1w3Q62MTgCQdbJwIzKCTZAbIVyDIh5ZVc9+h/W0uHbN4coaZ2M576QpPmcF ZwODhKRuqrtC+ZCBGrGeDVESVsTq4POkW2uP29xytbdEHRAuV0nBI3sK5OODMfdDAP ZL4ig4pnFtyEGwb5s+F9TvGSggB8e66DD6OcUjt3hMZyHC8uX93cuDdlemV5iKo1Eg ZPS8cOHA0dx3yK2XIo6DK71UVECo1A0NMQZZ7JwFHp1jcnEJErYLsZW1qLS2wF6kQR 4fLfr7kHSY+kQu1tVaLJC+GBLnoxrp8dhMOsei1Vw6qvGRSG/n7/8B4Ql4RYzYVP23 kG833FD/mPU1Q== Message-ID: Date: Thu, 18 Jun 2026 14:38:47 +0200 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] mm/lruvec: trace LRU add drains and drain-all requests To: "Vlastimil Babka (SUSE)" , Shakeel Butt Cc: JP Kobryn , linux-mm@kvack.org, willy@infradead.org, usama.arif@linux.dev, akpm@linux-foundation.org, mhocko@suse.com, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, kasong@tencent.com, qi.zheng@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, chrisl@kernel.org, shikemeng@huaweicloud.com, nphamcs@gmail.com, baoquan.he@linux.dev, youngjun.park@lge.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org References: <20260610195220.12403-1-jp.kobryn@linux.dev> <06122cae-e28b-4ded-a9dd-d380d31c5230@kernel.org> <1136baf3-3967-4202-9eaa-5fd667c235cf@kernel.org> <3149bc84-dd3a-43ba-826e-6364965fdafd@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/18/26 10:30, Vlastimil Babka (SUSE) wrote: > On 6/18/26 10:21, David Hildenbrand (Arm) wrote: >> On 6/17/26 20:18, Vlastimil Babka (SUSE) wrote: >>> >>> Yeah and I don't recall ever that a change to a mm tracepoint would ever >>> break someone who'd complain and we'd have to revert it. >> Really? :) >> >> Read the context of the link I posted once more. > > Ah, I see. I've only read the single mail from Steven that referred to the > old powertop breakage and didn't notice the context. > > But I don't think these worries should stop us from adding easily usable > tracepoints. Steve explained a way how apparently scheduler people are handling it without trace events. You can always remove/modify tracepoints, but not trace events. Anyhow, just wanted to mention it, because so far MM didn't rally know about this implication. -- Cheers, David