From nobody Fri Dec 19 03:42:39 2025 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 52F0426E62F; Wed, 26 Feb 2025 06:37:02 +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=1740551823; cv=none; b=NfSljTLGzQR1G+F/UZDx8SXFe5yGSURC4G6tDUPDcDS4xxtq3Nc2IxUYpgNb7iNnbM1cyn/S0PvaKgxcOQVqLobEBr+QHuK3+C3cNDyxPLc/Nj81uHO+1l3ZCEUxnoGioz/n/UF+G+5cuU967kmxrla7Bo6GIFPaB/oAB3X2V08= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740551823; c=relaxed/simple; bh=4J5vWHiHbtHqjwMC+hRbiipl4h9liEs0+TfNTGi8OuM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=WUh9AMjqt9hnVtNuW8/ajGbKpZr7lyyrfOqUzovzFK5OncCYdrzUaxe7i8oinJK5FXh+132fH4irp/RtCOs51pShlCJWgpNouWhOIS//QXc7xadwN4YW+mGf4/azcZPWB92r+ZhfZTQWEC7992JD8+XjzobrQj1k+sxqXm6VjmY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IY35+2jS; 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="IY35+2jS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A40BBC4CEEA; Wed, 26 Feb 2025 06:37:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740551822; bh=4J5vWHiHbtHqjwMC+hRbiipl4h9liEs0+TfNTGi8OuM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IY35+2jSTR0fwPWqE0pDaF10P37LWFVbjA8i0aglA/xKkrkdRBuW0AFLyuSa9KeHM pL7QeBCioMTspDME/Oi5tgLtMj3Ww5A1LPrqqmL+8dn/I3P/H+2ATvr7HkujdVpKi+ kHsu0DgCV4rIYvS/nH7GWwA5/FyIk/sNfWnIPacPHqL0MUoFtHZ4yCGO0syynawauK o6NDT1eHtNQSJhVYcRQ8EP8uA+lKkSVaQWO6RUtD4CnGHJnBTN6fPLTNtOzqrfcU3k V9DFeIAiANVX3zwg0kvelgpgrf764O4s+SgKVbqY4L3lCILw+abR5640X7UDPvdUnp MicgMxBby5e1g== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 07/13] mm/damon/sysfs: remove damon_sysfs_cmd_request and its readers Date: Tue, 25 Feb 2025 22:36:45 -0800 Message-Id: <20250226063651.513178-8-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250226063651.513178-1-sj@kernel.org> References: <20250226063651.513178-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" damon_sysfs_cmd_request is DAMON sysfs interface's own synchronization mechanism for accessing DAMON internal data via damon_callback hooks. All the users are now migrated to damon_call() and damos_walk(), so nobody really uses it. No one writes to the data structure but reading code is remained. Remove the reading code and the entire data structure. Signed-off-by: SeongJae Park --- mm/damon/sysfs.c | 24 +----------------------- 1 file changed, 1 insertion(+), 23 deletions(-) diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index e5bcf019086f..1af6aff35d84 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1238,25 +1238,6 @@ static const char * const damon_sysfs_cmd_strs[] =3D= { "update_tuned_intervals", }; =20 -/* - * struct damon_sysfs_cmd_request - A request to the DAMON callback. - * @cmd: The command that needs to be handled by the callback. - * @kdamond: The kobject wrapper that associated to the kdamond thread. - * - * This structure represents a sysfs command request that need to access s= ome - * DAMON context-internal data. Because DAMON context-internal data can be - * safely accessed from DAMON callbacks without additional synchronization= , the - * request will be handled by the DAMON callback. None-``NULL`` @kdamond = means - * the request is valid. - */ -struct damon_sysfs_cmd_request { - enum damon_sysfs_cmd cmd; - struct damon_sysfs_kdamond *kdamond; -}; - -/* Current DAMON callback request. Protected by damon_sysfs_lock. */ -static struct damon_sysfs_cmd_request damon_sysfs_cmd_request; - static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *att= r, char *buf) { @@ -1555,8 +1536,6 @@ static int damon_sysfs_turn_damon_on(struct damon_sys= fs_kdamond *kdamond) =20 if (damon_sysfs_kdamond_running(kdamond)) return -EBUSY; - if (damon_sysfs_cmd_request.kdamond =3D=3D kdamond) - return -EBUSY; /* TODO: support multiple contexts per kdamond */ if (kdamond->contexts->nr !=3D 1) return -EINVAL; @@ -1796,8 +1775,7 @@ static bool damon_sysfs_kdamonds_busy(struct damon_sy= sfs_kdamond **kdamonds, int i; =20 for (i =3D 0; i < nr_kdamonds; i++) { - if (damon_sysfs_kdamond_running(kdamonds[i]) || - damon_sysfs_cmd_request.kdamond =3D=3D kdamonds[i]) + if (damon_sysfs_kdamond_running(kdamonds[i])) return true; } =20 --=20 2.39.5