From nobody Thu Oct 2 14:13:12 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 46993CA5E; Tue, 16 Sep 2025 03:35:18 +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=1757993718; cv=none; b=IWECSYYtFZeRxR9YFKDsz6I1HQChY7T/GNZUtd/KTwjMATjxKelyPt3WcDteEoas3vDQuFwzOQ0tvtTec8HHF8SOkjtO/MxvlnXKv5hbemr5jbBBj0ZZjHT2HuEBx9seEpoOofWNHG5g4cZ1lHvcFCNlJ6RgxgoSs8YMDX9+D10= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993718; c=relaxed/simple; bh=9JcNBf3R6YvBmotNSylUCQN1TyYW4gyunQci2uE4WFk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=IQvA8PLXmx/IW8Kr2wOcWmXCt6ofUnMYdSQHGn6oXpuyRHSPf8S0+FMMuw1jRodOeM4jo87r3kgRZGK5l61X+WcEjIFegfaPzmj+yBFpLPIWoNWsPKKF3W4Ij9JCi5PN0JA2/6k2gV4BukhfNuO4cW9dNJCKfxFRft0nWCQEIGc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m5leU4h2; 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="m5leU4h2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2DA3C4CEF9; Tue, 16 Sep 2025 03:35:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993717; bh=9JcNBf3R6YvBmotNSylUCQN1TyYW4gyunQci2uE4WFk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m5leU4h24iIaQ6mZznhs9PW6jvp8aW8gZKhwvsdZb92V5iSdWE4qTRHkBXPc3DSlN zf8/lD+fNNViNqCKK93TyvvbwHLPBUJF3+Gc3SzYGR1EY/n7VxH2Mkd5qsJseb5d3X cy2kjGjooVQEZx/AMAxwPeysfx1rdiKEvykqzJ8jXW8euso5Q4uuqD+d919dr+HXZ8 dvntW0cZb1QExRthOwA6JBaPgI0uwI82JcchB/nd5BYH/Q7AMBkkmACjfcAA48toSF Z/+/OaQ+E2AB0j661UN20M8C9o/mtPmEMy/PF+j5A4Jf60ut8zTIiRKvOmqMet24Tv fBPY6Stm1IdMQ== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 1/7] mm/damon/core: implement damon_initialized() function Date: Mon, 15 Sep 2025 20:35:05 -0700 Message-Id: <20250916033511.116366-2-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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" If DAMON is tried to be used when it is not yet successfully initialized, the caller could be crashed. DAMON core layer is not providing a reliable way to see if it is successfully initialized and therefore ready to be used, though. As a result, DAMON API callers are implementing their own hacks to see it. The hacks simply assume DAMON should be ready on module init time. It is not reliable as DAMON initialization can indeed fail if KMEM_CACHE() fails, and difficult to maintain as those are duplicates. Implement a core layer API function for better reliability and maintainability to replace the hacks with followup commits. Signed-off-by: SeongJae Park --- include/linux/damon.h | 1 + mm/damon/core.c | 10 ++++++++++ 2 files changed, 11 insertions(+) diff --git a/include/linux/damon.h b/include/linux/damon.h index aa7381be388c..cae8c613c5fc 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -938,6 +938,7 @@ static inline unsigned int damon_max_nr_accesses(const = struct damon_attrs *attrs } =20 =20 +bool damon_initialized(void); int damon_start(struct damon_ctx **ctxs, int nr_ctxs, bool exclusive); int damon_stop(struct damon_ctx **ctxs, int nr_ctxs); bool damon_is_running(struct damon_ctx *ctx); diff --git a/mm/damon/core.c b/mm/damon/core.c index 775121ae7a9b..93848b4c6944 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -2863,6 +2863,16 @@ void damon_update_region_access_rate(struct damon_re= gion *r, bool accessed, r->nr_accesses++; } =20 +/** + * damon_initialized() - Return if DAMON is ready to be used. + * + * Return: true if DAMON is ready to be used, false otherwise. + */ +bool damon_initialized(void) +{ + return damon_region_cache !=3D NULL; +} + static int __init damon_init(void) { damon_region_cache =3D KMEM_CACHE(damon_region, 0); --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 6620C260565; Tue, 16 Sep 2025 03:35:19 +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=1757993719; cv=none; b=Zh4JHLwLla9WngQ4GPc+yqlffKEpO0KtWiasPzOLPt5TxO9g0XnSJCigm+W6XEoaKOMB1oPp7MyA23BULVNBVOiNUYGigoKezZCG055CwHvvHswpW4EcOaXZ/orKpfJPibgI7ykqkZHncsOVrr/CLPnEUJKDbSuqgo4t0RL7dZ4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993719; c=relaxed/simple; bh=yq6FzsyzX8HDFFWIsvaokYnQzl9M5W1Jr+HzsSN6nWg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=A4tJAOYHP1i1B/60vg/xjbYLeUrqs96EJQKelV67/mPHwtQU1H0lmT1MQ9MOLU1uQ0AtYMTlO1WfYEQOvy3EY0WTX0BYIBlQyJwkeLXFCltICBnWG1fXwgIaVnK850PEer6thQt1N7P7Pczb8Zj8WNWZUPqbsRif5yO0nfqD9aM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZgVIllP7; 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="ZgVIllP7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1D41C4CEF9; Tue, 16 Sep 2025 03:35:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993719; bh=yq6FzsyzX8HDFFWIsvaokYnQzl9M5W1Jr+HzsSN6nWg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZgVIllP7jG1t5xaNp6Ej7+6h6D0S3fE4uC/XLFrEWCBoHupYxjo9jV8rDMtz0S3LQ nSZfP4F1iftVGRQFLXoEfzfEu6hrCwigUaTVghy+Uh2475SNcT6Vc+ZaBN19ZR1F7q EH9fdMvVUtRXl8y01N9V8dL0SoALaK3UjU3OBTnN4dA7SiZvo/f6g4ZUOpWgRx8HZO j4gSlqY+X6drLgbfTvW7KyNnpbH/6dU1S6yy16KXPRd92YW5bNuTuSRb95+gx1XoQh xIcz6dCNGllxAKbbucMBlLLCZTKCiaAsrI0OouakMAihQ0vW/nF68rW7qsF81YRvP4 kWSCCN3mKRzzw== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 2/7] mm/damon/stat: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:06 -0700 Message-Id: <20250916033511.116366-3-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_STAT is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- mm/damon/stat.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/damon/stat.c b/mm/damon/stat.c index 87bcd8866d4b..c4fbd8cfa5eb 100644 --- a/mm/damon/stat.c +++ b/mm/damon/stat.c @@ -214,8 +214,6 @@ static void damon_stat_stop(void) damon_destroy_ctx(damon_stat_context); } =20 -static bool damon_stat_init_called; - static int damon_stat_enabled_store( const char *val, const struct kernel_param *kp) { @@ -229,7 +227,7 @@ static int damon_stat_enabled_store( if (is_enabled =3D=3D enabled) return 0; =20 - if (!damon_stat_init_called) + if (!damon_initialized()) /* * probably called from command line parsing (parse_args()). * Cannot call damon_new_ctx(). Let damon_stat_init() handle. @@ -250,12 +248,16 @@ static int __init damon_stat_init(void) { int err =3D 0; =20 - damon_stat_init_called =3D true; + if (!damon_initialized()) { + err =3D -ENOMEM; + goto out; + } =20 /* probably set via command line */ if (enabled) err =3D damon_stat_start(); =20 +out: if (err && enabled) enabled =3D false; return err; --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 7932C260565; Tue, 16 Sep 2025 03:35:20 +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=1757993722; cv=none; b=goWYHFCyVmogFHcKcWcGtJMwZ+v40TO4xbpcixiytVXzqTr+Gj1o242v2tTIttK5isea7DTsD2V3q2cduxcA/3CMpJQT3k0BaYvVqlYIl+ivP7nLAnR4akJQBZK2e7PhIlvuRHMXVN/MhtBKOt9/SEANc2y2IrW4ELPgWxRYpsw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993722; c=relaxed/simple; bh=AfFc3OpSjbhPeNbz+Yb9iOakhYwHCt/NFSR70/mcjZU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=RgxWpPgRA3A2oAMNeDU4yYpE0hkbv1A1TeyPdUMjVFhP4443AuPi0j3ONrSVPq1/42pCbBtj3kTsGNOoQ8SH7SO4RV7wzDPec22FE/OMLnJLBo99dwDC57peDEsdqz1mISEuiT1xIPGc4Ys7sYkS1ReAK/dPA00o9ug2U0tjniw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iCaLOGwZ; 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="iCaLOGwZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DE366C4CEEB; Tue, 16 Sep 2025 03:35:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993720; bh=AfFc3OpSjbhPeNbz+Yb9iOakhYwHCt/NFSR70/mcjZU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iCaLOGwZMAAJUlm+iZk8xywaYfHX/rCIdKmJ0AenkSvV/KiDRTAceiXlRsY9M6iVV T8LNEoolqh6ge7VDc6/k7bzJi3vckF6xt/TBebnEU5PvB2Oty5fJzrOVZju5FXG2Km BVVtijmUVBPg8wgA1z3ID0USW3grfC7+XHZXTjAuB7xMGKRG2E5BjK9PF78HnlIuKF 6pRTFaxvX10IxERc8GeQi30SaP5AvT7BH0twMDd9Dg3fxuT0SlLv+htgCIuBJn+Ewb fcbVv1jlhhS+GqB7Po4dt8YdoOHZ/nk1euOotZUHBPBCJAC9lCsJepc+s4YRrzeNow GR/ShJkmHhW9A== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 3/7] mm/damon/reclaim: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:07 -0700 Message-Id: <20250916033511.116366-4-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_RECLAIM is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- mm/damon/reclaim.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index 590f9d6c55ef..7ba3d0f9a19a 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -349,7 +349,7 @@ static int damon_reclaim_enabled_store(const char *val, return 0; =20 /* Called before init function. The function will handle this. */ - if (!ctx) + if (!damon_initialized()) goto set_param_out; =20 err =3D damon_reclaim_turn(enable); @@ -372,8 +372,13 @@ MODULE_PARM_DESC(enabled, =20 static int __init damon_reclaim_init(void) { - int err =3D damon_modules_new_paddr_ctx_target(&ctx, &target); + int err; =20 + if (!damon_initialized()) { + err =3D -ENOMEM; + goto out; + } + err =3D damon_modules_new_paddr_ctx_target(&ctx, &target); if (err) goto out; =20 --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 7940626FDA8; Tue, 16 Sep 2025 03:35:21 +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=1757993722; cv=none; b=sngm5MwUMPcQBo0OhXBmOVtpnu/642ym2obeInTWkVXoUWhhVYAVREU0MGEdwMrKT33sYg3BP/Gy89NThKY++I4o6kn3f2hLrNSx/0iR0Rp73OrXdpHRzvjmH5iwOdcd4w02HS5cj2ldhWLqEtMwE0l+mXSd1wZYp0ZdMDrLKGI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993722; c=relaxed/simple; bh=jSyChxhp2q57cPUh41M0fEVHkYfztaaT3v+fVBcDkyE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=XfCACGRNm7bqzZN+m//qd+KFuAm56WbZpeSxlkg8UdjsMEE6mXcK80JU/Ml0DEw5J5dJXT/yOCEteAbU+ze9qKtidH/J7JYUHumDxWXaw2KF8cFfH6RAVzL7oRAiaiKXbPtFuauebHVtvxlapw4ESBTQ03AQ/i0UCCIjSHtcL6w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=orfNy6DZ; 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="orfNy6DZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF489C4CEFE; Tue, 16 Sep 2025 03:35:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993721; bh=jSyChxhp2q57cPUh41M0fEVHkYfztaaT3v+fVBcDkyE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=orfNy6DZUAp3GECznrx4oiXg/9pB061b0r3o27o0f0ZJscgUtwEI5JqwK4Co/KrXy yaNtCi+UpfwZqqW7g3XqYNHTSYdu+FGDETrxw20d1UMeMJjxTp7aRn+0SFeJKcyBNT DzbDAeK1n0Tq9I1owIgh9eRtfJeUI0CjWVO7mCBs8sW+pob8csaBqTczIPe6SA93UB ioAz63GmsdAXpimgbDXPlAXHFU/YXLarYZFB/fv6SKznE9dmDVSbXqaeHZz6dflQBC rxZe4GjdLtA4AyGOqR48dJqjpz4nsBl9+DWt/U4ckeQDw7H0iLIIxlq4CRFaBKw4uJ 9pycIiU9R1Ilg== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 4/7] mm/damon/lru_sort: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:08 -0700 Message-Id: <20250916033511.116366-5-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_LRU_SORT is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- mm/damon/lru_sort.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index ab6173a646bd..42b9a656f9de 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -345,7 +345,7 @@ static int damon_lru_sort_enabled_store(const char *val, return 0; =20 /* Called before init function. The function will handle this. */ - if (!ctx) + if (!damon_initialized()) goto set_param_out; =20 err =3D damon_lru_sort_turn(enable); @@ -368,8 +368,13 @@ MODULE_PARM_DESC(enabled, =20 static int __init damon_lru_sort_init(void) { - int err =3D damon_modules_new_paddr_ctx_target(&ctx, &target); + int err; =20 + if (!damon_initialized()) { + err =3D -ENOMEM; + goto out; + } + err =3D damon_modules_new_paddr_ctx_target(&ctx, &target); if (err) goto out; =20 --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 7939626FA4E; Tue, 16 Sep 2025 03:35:22 +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=1757993722; cv=none; b=sSn1esUlHu71LHixBiW40T6ZTcPOMqzttJbRY3FaBOWj21Un1IQ/iKRX7/d/7vmWp7JdXyyOpirnpYgI2IH2xqcwj2qhdS/B/IubAlDCvRf+15smSYABwb8oMwiDYEl39fco1Y4TQm9yP130j115FpcLXdTrnACaIM6Z6VLnATg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993722; c=relaxed/simple; bh=2demp7SZfocNtJOdY3h9yRpOtgZXlewJOxyAe06bXV0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=hrjERYLx8TfsKnj3Ac+pXHMvUnYKr2Zr8UtnQkabHMTB43vRQrT74BIDefXb/jmCSdB905+l9Aze6Sel0F/MN084k44ll8uic0PK/pBbckOOso5knSPqQsi6u8Yaiv0xzN1wKlZL68VC5fEtlOXZl0LKuRZWabi0B6EmNajLCqI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cGZfcUg7; 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="cGZfcUg7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0846CC4CEF7; Tue, 16 Sep 2025 03:35:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993722; bh=2demp7SZfocNtJOdY3h9yRpOtgZXlewJOxyAe06bXV0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cGZfcUg7EYIo0PMGPLm0zQMT++5sADBSnFLPvKL/Xi2D9s8FjnUMCJZ93k3AwBbUN CTiePydCLnUhLempDvgCh7ZKz+gs55peHtUSLOLR39RM0HEcDxJbCsWlHnANqGXmvm TP56I41Myk/vI7UsifpnKAi4Yl8T0i3gGwtkGoV5JW5PabKlafetYlWe05pNa9GNPo 2W2+P0Jl3cHihLfzuLCNbCraB6DgnDTlNcfda12wR7ve8vW4xDksqYWLKK3NLD379/ 1zRtVoBZJVkI0KPvNSjb3nJTDoyCzv/xJZmroq1uzljEq6h/VmmcubJ57FnghDbvOe sEpknD+Vbb8hA== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 5/7] samples/damon/wsse: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:09 -0700 Message-Id: <20250916033511.116366-6-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_sample_wsse is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- samples/damon/wsse.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/samples/damon/wsse.c b/samples/damon/wsse.c index 21eaf15f987d..799ad4443943 100644 --- a/samples/damon/wsse.c +++ b/samples/damon/wsse.c @@ -102,8 +102,6 @@ static void damon_sample_wsse_stop(void) } } =20 -static bool init_called; - static int damon_sample_wsse_enable_store( const char *val, const struct kernel_param *kp) { @@ -117,10 +115,10 @@ static int damon_sample_wsse_enable_store( if (enabled =3D=3D is_enabled) return 0; =20 - if (enabled) { - if (!init_called) - return 0; + if (!damon_initialized()) + return 0; =20 + if (enabled) { err =3D damon_sample_wsse_start(); if (err) enabled =3D false; @@ -134,7 +132,12 @@ static int __init damon_sample_wsse_init(void) { int err =3D 0; =20 - init_called =3D true; + if (!damon_initialized()) { + err =3D -ENOMEM; + if (enabled) + enabled =3D false; + } + if (enabled) { err =3D damon_sample_wsse_start(); if (err) --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 B6E47277C81; Tue, 16 Sep 2025 03:35:23 +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=1757993723; cv=none; b=Illy52tw8zUmFTmSc8ar+5Ar3K5Nj/zJYX9oUzMbIQVU1o48n/aenqkJqM3EEL/fJxniJ42Z/q+/p/ma3LUiObQCfZHSwkLc27ljgBY2EEeH24Td0n7wK+AEOwFLl47MnjDBmWmnd/wQqhiQLOrlXlnSUVqVY11K1h73EG5fV9s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993723; c=relaxed/simple; bh=8oAmMgNUvcFWbF3KtriZccsEdzvp1RE+WJ1o1RTAqkA=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Cni4LINjZ5z2Jw+ukMJgR3RUJ9P17vBffbE0hgfkQbqXFrMKYY9G6T5E8PROnyuFxZQ2FzOmtjwU1nDWlx7bkcaZ14RptFUzCVL6aZGn7OneD4ACCvhUml206OUzKZk50ralF39/Sl85pm9+gEz3RsvDfeRCGG26hKAS6qbwIh4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dhCRJQQ8; 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="dhCRJQQ8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2818AC4CEF7; Tue, 16 Sep 2025 03:35:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993723; bh=8oAmMgNUvcFWbF3KtriZccsEdzvp1RE+WJ1o1RTAqkA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dhCRJQQ8QgGNEa5PQd5V6Jv0j+x3drr4a3j4gjBXGWjf0xXYigd/519UPcQLOemOs V7ogujCxEc0LWVFzUMthyyjjM9Rbi4Dr5o7lHKFGQGGm+ZQDsG6PTRyGx4gNaFnF49 F4nQqtJZdmEwSNsNnyoUeH5VAfcS9+ZyKzrxkYXhdKmZ5HPR2XqUXn7VqQx91HF+3D zicoTmUybUf1DPFOHe33KO7Nyag6zAy/JUgBeH+RAxcSK1Z0e0UIBOS0NBMSVZsb4o ksfkyMu9Gw0NIFaYu9Yo9Ju5P6eQxgqE8bfWmYpycY4cUlTtAZM/eaKAwakH7z1YCQ 79hF+rrolVA5w== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 6/7] samples/damon/prcl: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:10 -0700 Message-Id: <20250916033511.116366-7-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_sample_prcl is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- samples/damon/prcl.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/samples/damon/prcl.c b/samples/damon/prcl.c index 0226652f94d5..b7c50f2656ce 100644 --- a/samples/damon/prcl.c +++ b/samples/damon/prcl.c @@ -122,8 +122,6 @@ static void damon_sample_prcl_stop(void) } } =20 -static bool init_called; - static int damon_sample_prcl_enable_store( const char *val, const struct kernel_param *kp) { @@ -137,7 +135,7 @@ static int damon_sample_prcl_enable_store( if (enabled =3D=3D is_enabled) return 0; =20 - if (!init_called) + if (!damon_initialized()) return 0; =20 if (enabled) { @@ -154,7 +152,12 @@ static int __init damon_sample_prcl_init(void) { int err =3D 0; =20 - init_called =3D true; + if (!damon_initialized()) { + if (enabled) + enabled =3D false; + return -ENOMEM; + } + if (enabled) { err =3D damon_sample_prcl_start(); if (err) --=20 2.39.5 From nobody Thu Oct 2 14:13:12 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 C4F7327B35D; Tue, 16 Sep 2025 03:35:24 +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=1757993724; cv=none; b=KiHVXrJPEebzoOYxqXMUu+zBYjww124I2dEgIg/Yxc5iVGjrRJtSfAJhaou0qt47VmXWOn/zLScN8spIgktkwLRq3v31CzaGOQFHABJtzRYGVXZwFGZjRhdYw/BGxbWdTILTnWLcCP1XPuyrhMjwKhoA8r790kMDYzT298TgJgY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757993724; c=relaxed/simple; bh=4uQscG4mYr4g+dERacoLlCCtLcp3o3ScovLzzqmdpAo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=TaWXebTW+DjxHZLQliqPI5mCe7WWshKFNTvnhaRbwYDqePG0h/IFbkeUH0mDOMx7c1Dqu5dibfxTI4eYuBNmYVCw0gmMxh2nANk9i9o57nh7kyED9Y4fKLZNWwBGQE9SdKlrze763F/XJzoNCkJ/8dk18CVpQKekQGrK8eBYBJ0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GswUYaDo; 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="GswUYaDo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 39857C4CEEB; Tue, 16 Sep 2025 03:35:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757993724; bh=4uQscG4mYr4g+dERacoLlCCtLcp3o3ScovLzzqmdpAo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GswUYaDoamgG2C1fR5wV2glRHaeU2ehx1anVdkERZyRo8fOlc1aeI5cWSmpAXxkzY QQ+fAztPPkjGPGDQDmwTywr6x+/ai7QaVZiQsW/tNsk+3STv0BOSUIFL++v5mNfPUV 1fDqc3qT9fr6vrYJr9YeIbQRUYHKUHTe4IE86+lejqcEFRhi4QTJrB5e17ngGfKgWA J7DsbY3hyzBg2ViujYAtCqPhGghty1jWBjXovXvb2W80VXGnRTZ8mjvQ5k75SmKnCR DPABkkkbjn5E8O+T8kW+rt8d5XCWHiv5+HjDu9Pg0mnB3l2d/Ow0O+kZgqOnMsrm5O yYKPe1tJXw/Jg== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 7/7] samples/damon/mtier: use damon_initialized() Date: Mon, 15 Sep 2025 20:35:11 -0700 Message-Id: <20250916033511.116366-8-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250916033511.116366-1-sj@kernel.org> References: <20250916033511.116366-1-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_sample_mtier is assuming DAMON is ready to use in module_init time, and uses its own hack to see if it is the time. Use damon_initialized(), which is a way for seeing if DAMON is ready to be used that is more reliable and better to maintain instead of the hack. Signed-off-by: SeongJae Park --- samples/damon/mtier.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/samples/damon/mtier.c b/samples/damon/mtier.c index beaf36657dea..775838a23d93 100644 --- a/samples/damon/mtier.c +++ b/samples/damon/mtier.c @@ -193,8 +193,6 @@ static void damon_sample_mtier_stop(void) damon_destroy_ctx(ctxs[1]); } =20 -static bool init_called; - static int damon_sample_mtier_enable_store( const char *val, const struct kernel_param *kp) { @@ -208,7 +206,7 @@ static int damon_sample_mtier_enable_store( if (enabled =3D=3D is_enabled) return 0; =20 - if (!init_called) + if (!damon_initialized()) return 0; =20 if (enabled) { @@ -225,7 +223,12 @@ static int __init damon_sample_mtier_init(void) { int err =3D 0; =20 - init_called =3D true; + if (!damon_initialized()) { + if (enabled) + enabled =3D false; + return -ENOMEM; + } + if (enabled) { err =3D damon_sample_mtier_start(); if (err) --=20 2.39.5