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 217F6C02188 for ; Tue, 28 Jan 2025 02:11:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6FC632801FB; Mon, 27 Jan 2025 21:11:53 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6AC4E2801F2; Mon, 27 Jan 2025 21:11:53 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 573DD2801FB; Mon, 27 Jan 2025 21:11:53 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 390D82801F2 for ; Mon, 27 Jan 2025 21:11:53 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id B296680AD9 for ; Tue, 28 Jan 2025 02:11:52 +0000 (UTC) X-FDA: 83055234864.17.CE9E295 Received: from mail-ed1-f43.google.com (mail-ed1-f43.google.com [209.85.208.43]) by imf11.hostedemail.com (Postfix) with ESMTP id BD20440015 for ; Tue, 28 Jan 2025 02:11:50 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=ZHxeEim9; spf=pass (imf11.hostedemail.com: domain of richard.weiyang@gmail.com designates 209.85.208.43 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738030310; h=from:from:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=i6stozJVBdj0bSk5UJ5wJ3rDwy7nTHJG8ZkFhMYJ0Q4=; b=7XSezjhYUZ8ahvEBPcenBZtGjvAX8AXCTgbAWCfNjYKSNXRTE3jZ/Hl50FuxOhhtG98Swc UPo9d5XmSnyJiaYdvxLJCdIa+F9yH8cX5iAXnZjimawo499OwEq/rTDa4cugl/sL03+o3D f6g5PQfLu1yK49/rH/MshvoFKymVzaU= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=ZHxeEim9; spf=pass (imf11.hostedemail.com: domain of richard.weiyang@gmail.com designates 209.85.208.43 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738030310; a=rsa-sha256; cv=none; b=Egng55sw7C+1yK3DbGUj978hYzwChQVF1Jl4M3nYj9EunMfeqUoLOnCsyvth4dspua0JWw YoxpbJHP3plugo9CB3IPDIiHRYR6XxmsIxOaXr9nbMncD6RdtSiuB+JCMZ4/G/9M6uZ1RN FsNnkURgkuhs6JR3o7Cuwxpyws7D+xU= Received: by mail-ed1-f43.google.com with SMTP id 4fb4d7f45d1cf-5d3d479b1e6so7375254a12.2 for ; Mon, 27 Jan 2025 18:11:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1738030309; x=1738635109; darn=kvack.org; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=i6stozJVBdj0bSk5UJ5wJ3rDwy7nTHJG8ZkFhMYJ0Q4=; b=ZHxeEim9rPLwuM1rTV6APaOpRJ6HMlVOLykRM/s6s8M/Vua8lzQjhFxK2AuqxYa3/n tRFJOcWthZqbXYGyUn+i5MAo0JqO+M2nfQwjRTMLIVH2Pbft4r0XtizUxXJsvIm74/aT AKOOl4I3IdqaG0U7xxwd4SL4V/ZMDQ77/4Tvv/6eizRx4xgfVkr6n3Kqae3t7yJpEHnH 2L4ottMqw9h2Z6wBF50c1OCXXm+CVeHe8lwms4gRdf0KI5q0hPg4xH54gqg8LI75MFKy emLLH7oakr5gQ1QkvpqfkXXqQ8scG/JnvWK67YJ6kh7cydzV/DvoN8YvaFwgk/Vfl5UT z8Zg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738030309; x=1738635109; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=i6stozJVBdj0bSk5UJ5wJ3rDwy7nTHJG8ZkFhMYJ0Q4=; b=KKRAHxkMCBcGXQQ4FxVWstFIQ6sw6TCaORN6tiBbdBH7LOQA9W0M8Siy+iCb4IkNL8 DBLrnqDtuWxz9hkSfi16P0ltwX1Amhpg10jhD3iFdpW/qiZq7yUOYsjoVdoGSY/Jfkbz IvyVJHt1lKIOaZHqyB+a1GfzGDwmM3NWmxWlxX1a5tNyQ0a+jnnldQpnQKD+xKUHuQfd znBEfKcXfzjzwUyKafkKGUSDgODH3qXn0eUomE9x+0xcZ0djXfFpW/SaFrElg+tP8S7r SAPSQeiqP6WLOHJmDyQnypAfN66XrpGEigJphF4Rj59TLj0KuvopOOqag+huvdiAMaru oZGA== X-Forwarded-Encrypted: i=1; AJvYcCV2nFVciWHvvGyRjSmAdyzylZrcBXfhuQBPEOEjkbl8Iyd57kMxd3y3Rgn2RnDilj0oBnvQzwLGIg==@kvack.org X-Gm-Message-State: AOJu0YyBrGmLH3zr7c1Cv+NOuHEEf0lnB5Uq+h3aECTNuM6CaetlP1Hv h7e5135Z4rsaBUaPd7SlVuqXuDXs+vhn2yV3m4MmhcZhC/YecUkIn4rSyecB X-Gm-Gg: ASbGncvwgv7m5C9l+ZaZreSaZU2ptaP5wM1PlQnxwUAeE/sHNzSYm56iM8yAhoMPJj2 YxuEhrdaeSjKfmsM1cV8yuSYewuWT0OvdAOCyz/4TCOaQd6+RIhZyuTXOVlsb+c1IfpwokTUks8 xk+hN0ttQ2LZPkVJLcuU3Ke5mGEMy2K9peXIK1V4I2ort/w7o9kkoNZrCh0sQ7yVy7Di33w8rMJ 62Erh0Az2EfHqBmrKIK8ZeEoWNBYdQa8+ybo+CZkiVHhWl54yp9R2GvRNpleuS+DZ+HWg/2uHEx YHDgsWmDfLTEZ44= X-Google-Smtp-Source: AGHT+IHwTTXoiNHvcYNSE+t7ZgEjN8MNfdLp6bfC1nD94KT350U6nn9SkEFvhumz3oZ98OGDcTHkiw== X-Received: by 2002:a05:6402:3587:b0:5dc:100c:1560 with SMTP id 4fb4d7f45d1cf-5dc100c1768mr48623465a12.18.1738030297592; Mon, 27 Jan 2025 18:11:37 -0800 (PST) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-5dc4876d183sm1380224a12.17.2025.01.27.18.11.35 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Mon, 27 Jan 2025 18:11:36 -0800 (PST) Date: Tue, 28 Jan 2025 02:11:35 +0000 From: Wei Yang To: "Liam R. Howlett" , Wei Yang , akpm@linux-foundation.org, maple-tree@lists.infradead.org, linux-mm@kvack.org Subject: Re: [PATCH 0/7] spanning write related cleanup Message-ID: <20250128021135.fxfb2muboeug7jjb@master> Reply-To: Wei Yang References: <20241127012753.3393-1-richard.weiyang@gmail.com> <20250117054942.w6vgrllnaasjaww3@master> <20250124013412.2vpf7davx63s377d@master> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: BD20440015 X-Stat-Signature: 85zwgwofhj18dc1oc6iwbmi7gitmtjad X-Rspam-User: X-HE-Tag: 1738030310-431295 X-HE-Meta: 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 EtE0GAfU 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000031, 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 Mon, Jan 27, 2025 at 09:36:11AM -0500, Liam R. Howlett wrote: >* Wei Yang [250123 20:44]: >> On Thu, Jan 23, 2025 at 12:52:40PM -0500, Liam R. Howlett wrote: >> >* Wei Yang [250117 00:49]: >> >> On Wed, Nov 27, 2024 at 08:31:13AM -0500, Liam R. Howlett wrote: >> >> >* Wei Yang [241126 20:28]: >> >> >> Here is some cleanup related to spanning write. >> >> > >> >> >None of these fix anything, but do fiddle with code that's pretty >> >> >critical to the kernel. Most of the changes will be immeasurable in >> >> >change but carry risk to causing subtle changes. >> >> > >> >> >Some are simple removal of returns that aren't used while others change >> >> >things because you think they are probably the equivalent. This seems >> >> >like unnecessary chrun at this point. I'm all for efficient code but >> >> >this is getting a bit much, some of these are just preference of what to >> >> >use that will already exist in the cpu cache. >> >> > >> >> >I'll get back to you when I dig through them, as some need a deeper look >> >> >for sure. >> >> > >> >> >Liam >> >> > >> >> >> >> Hi, Liam >> >> >> >> Would you mind taking a look when you have time? >> > >> >Yes, I'll have a look soon. I don't love changes that dive deep into >> >complex code that results in no gains (performance or feature wise). >> > >> >It's also odd to have simple "this return isn't use" and things moving >> >code blocks to be executed only in certain scenarios, as the difficulty >> >to verify the latter is much higher. >> > >> >Can we please limit changes to areas where there is a performance change >> >or coupled with a change that is needed? ie: stop sending patches that >> >change things unless it's with a feature or improvement (performance or >> >otherwise). I'm just not convinced some of these are worth the >> >cost vs risk. >> > >> >> Ok. >> >> So you would drop this patch set or still want to take a look? > >I was going to look at it, but after I send my reply, I received a >report of an issue caused in a certain configuration that caused the >stack frame to grow out of the configured 1024 limit, which was tracked >to a patch you added to simplify a previous function. > >So, I think we should drop these patches since they don't make a >measurable difference and are not without risk. > Hi, Liam Maybe I found one issue in current code that we miss to set the root node dead. Before sending a fix, I want to check with you first. Current behavior: mte_destroy_walk() mt_destroy_walk() if (mte_is_leaf()) goto free_leaf; mte_destroy_descend() mte_set_node_dead() <-- set node dead here Usually we set all node dead in mte_destroy_descend(). But if the maple tree has just one root node, it jump to free_leaf without set it dead. It seems not correct to leave a non-dead node. Is my understanding correct? >Thanks, >Liam -- Wei Yang Help you, Help me