From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 5549532B98D; Mon, 29 Dec 2025 15:23:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767021783; cv=none; b=HBDSLN9JBfx90iJ1ZQWclDhDbtcZbQJqZAtQqC7VabkKzvcH8NPb4FiVK27HgKmFmLm45JR0HGT91oXkJ0XnaSnW/vj7aUmZW7Nn9gfBj2FlkRuxArrH75M7e0wcONdrcbV3/SDqrUUXddbJ23ENZOCa8Vq4zDnnZy/4t/6iM1Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767021783; c=relaxed/simple; bh=hjLy/PceNw58V9dV1arMQA3XkITKYMDJEG7qcaYiXd0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MJO+krvb63hP+mU+zyxT41G3iToMqT4gI+4fiN4dlqeHAEII5gWdPzu+xgvtAv53Fv+kQeHacHEm4MybkZqlJiBQI6Vhm1kac9JPbzgqEWx4ACLL2+rcpH36u4ZF6yoSaNhLzounC6uMnUL/ruTKaXjAINp3vLTsnk7+QVKhIcU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gasBn2fW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gasBn2fW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB7EEC4CEF7; Mon, 29 Dec 2025 15:23:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767021782; bh=hjLy/PceNw58V9dV1arMQA3XkITKYMDJEG7qcaYiXd0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gasBn2fWJ//NUxKL9tbdOzF2iOSzTNPiq5/m0pGiDe93U97Scwv8eD+9RETnfvY0O iuBi3UjXjvaEtfc63eKCkUcmLedLEFvXR5LG9JqmtusXEVqSiqbiKljn4YEjktnb6t 5gFWJ0txmmGVWitITkJJcCtmyqMDf56SELo8VTG8U0qqOVk39cnPO+MzCTb51nFEQD HikzV64qn7+vpXjI9Oj2oQAgiQj9mrA9+qa9MDmHNpTUdaZQo7JcfizQP0ov3cC7cP FKFM4sXj8GwVPFb7bKU/JpBr2Uju+jdPO2Mik+ceDzAhnUw84MhboGKReIV5liJ+x0 dH7xIrExMdh+w== From: SeongJae Park To: Asier Gutierrez Cc: SeongJae Park , akpm@linux-foundation.org, damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org, wangkefeng.wang@huawei.com, artem.kuzin@huawei.com, stepanov.anatoly@huawei.com Subject: Re: [RFC PATCH v1] mm: improve call_controls_lock Date: Mon, 29 Dec 2025 07:22:49 -0800 Message-ID: <20251229152250.78975-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251229145533.2437293-1-gutierrez.asier@huawei-partners.com> References: Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hello Asier, Thank you for sending this patch! On Mon, 29 Dec 2025 14:55:32 +0000 Asier Gutierrez wrote: > This is a minor patch set for a call_controls_lock synchronization improvement. Please break description lines to not exceed 75 characters per line. > > Spinlocks are faster than mutexes, even when the mutex takes the fast > path. Hence, this patch replaces the mutex call_controls_lock with a spinlock. But call_controls_lock is not being used on performance critical part. Actually, most of DAMON code is not performance critical. I really appreciate your patch, but I have to say I don't think this change is really needed now. Please let me know if I'm missing something. > > Initial benchmarking shows the following results > > > # bpftrace -e 'kprobe:kdamond_call { @start[tid] = nsecs; } Commit log shouldn't start with '#'. Please consider indenting the above command and below outputs of it. Thanks, SJ [...]