From nobody Fri Dec 19 13:24:57 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 C61C232143F; Mon, 8 Dec 2025 06:30:34 +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=1765175434; cv=none; b=ifv/5PM6Dm8wN7mgNW0i0q7XehX3/yGunGk6EXFJOiSHaYhFjjknY1r2RQgZddFxMgQr58XskWDDasKlDkVTh2zPBhjHG2WSpEwTmzg688f8Nc5aVQux/VvKeVUqz79McBO0+eMWmWIG7gLoQkzM6TwJvCGZzbbzlfxtdAsf/rw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765175434; c=relaxed/simple; bh=3JZCkxkL4i/kCYq9wc6IiaTGi5wDXb4PyYdbk+AUHf8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=b0xd4OPl/Kc7s8caZ9FQybG8wQ9QSw4ZKuqjbWRJszpqZSEDQWaJctvlXp905nGgKdcvzW2npqmyqgoireg0h6K/UaTpOLJBKZwtNmrrO8v9BKyxma0LtmXbe67fvHLcGKFuZIUH86ELUQkIYYNZflN1sEq9AKk9voy8fb95LJA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lPzC8mFh; 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="lPzC8mFh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0AD8C19421; Mon, 8 Dec 2025 06:30:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1765175434; bh=3JZCkxkL4i/kCYq9wc6IiaTGi5wDXb4PyYdbk+AUHf8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lPzC8mFhApK44AZvUzvwj+vo6IrDlAMEE5iJ9ohs4vVx8YFqcfCPEy4nxJfKP1ppg 6ZznWeeXOhkl3NdXCkNyJU1vNhCTA3vjJmkw8vn4SnWbB44QcpBDsEVdjjP7SCY4c2 lRXZOJ1wVVY6hvlcor6fZLEeZcUdvZ2wqlRGMwZwcslxW8ohkFxNZpLvEqmJycs4UK jOLUzQfTZMD45lsKWkW7xE3U0OYt6sG0g5PiUjkz3WJyt1t79cpLPtFIhiGsF6AEwY eIzvmmkUmC1s8ca5DE672uyCZFaE0sPqSuNXj8g+1pzRf4AkUgqzCih/TEz5hTeYbk y7ENPFpbIzg9g== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH v3 30/37] mm/damon/sysfs: support thread based access sample filtering Date: Sun, 7 Dec 2025 22:29:34 -0800 Message-ID: <20251208062943.68824-31-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251208062943.68824-1-sj@kernel.org> References: <20251208062943.68824-1-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" Add support of the threads based access sample filtering on DAMON sysfs interface. For this, add a new file for setting the threads of interest of the filter, and pass it to the core layer. Signed-off-by: SeongJae Park --- mm/damon/sysfs.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 3aac2aea6b0c..b96df2d2d17e 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -759,6 +759,7 @@ struct damon_sysfs_sample_filter { bool matching; bool allow; cpumask_t cpumask; + int *tid_arr; /* first entry is the length of the array */ }; =20 static struct damon_sysfs_sample_filter *damon_sysfs_sample_filter_alloc(v= oid) @@ -777,6 +778,10 @@ damon_sysfs_sample_filter_type_names[] =3D { .type =3D DAMON_FILTER_TYPE_CPUMASK, .name =3D "cpumask", }, + { + .type =3D DAMON_FILTER_TYPE_THREADS, + .name =3D "threads", + }, }; =20 static ssize_t type_show(struct kobject *kobj, @@ -888,6 +893,47 @@ static ssize_t cpumask_store(struct kobject *kobj, str= uct kobj_attribute *attr, return count; } =20 +static ssize_t tid_arr_show(struct kobject *kobj, struct kobj_attribute *a= ttr, + char *buf) +{ + struct damon_sysfs_sample_filter *sample_filter =3D container_of(kobj, + struct damon_sysfs_sample_filter, kobj); + char *str; + int nr_tids, *tid_arr; + int i, ret; + + if (!sample_filter->tid_arr) + return sysfs_emit(buf, "\n"); + + str =3D kcalloc(2048, sizeof(*str), GFP_KERNEL); + if (!str) + return -ENOMEM; + nr_tids =3D sample_filter->tid_arr[0]; + tid_arr =3D &sample_filter->tid_arr[1]; + for (i =3D 0; i < nr_tids; i++) { + snprintf(&str[strlen(str)], 2048 - strlen(str), "%d", + tid_arr[i]); + if (i < nr_tids - 1) + snprintf(&str[strlen(str)], 2048 - strlen(str), ","); + } + ret =3D sysfs_emit(buf, "%s\n", str); + kfree(str); + return ret; +} + +static ssize_t tid_arr_store(struct kobject *kobj, struct kobj_attribute *= attr, + const char *buf, size_t count) +{ + struct damon_sysfs_sample_filter *sample_filter =3D container_of(kobj, + struct damon_sysfs_sample_filter, kobj); + int err; + + err =3D parse_int_array(buf, count, &sample_filter->tid_arr); + if (err) + return err; + return count; +} + static void damon_sysfs_sample_filter_release(struct kobject *kobj) { struct damon_sysfs_sample_filter *filter =3D container_of(kobj, @@ -908,11 +954,15 @@ static struct kobj_attribute damon_sysfs_sample_filte= r_allow_attr =3D static struct kobj_attribute damon_sysfs_sample_filter_cpumask_attr =3D __ATTR_RW_MODE(cpumask, 0600); =20 +static struct kobj_attribute damon_sysfs_sample_filter_tid_arr_attr =3D + __ATTR_RW_MODE(tid_arr, 0600); + static struct attribute *damon_sysfs_sample_filter_attrs[] =3D { &damon_sysfs_sample_filter_type_attr.attr, &damon_sysfs_sample_filter_matching_attr.attr, &damon_sysfs_sample_filter_allow_attr.attr, &damon_sysfs_sample_filter_cpumask_attr.attr, + &damon_sysfs_sample_filter_tid_arr_attr.attr, NULL, }; ATTRIBUTE_GROUPS(damon_sysfs_sample_filter); @@ -1952,6 +2002,25 @@ static inline bool damon_sysfs_kdamond_running( damon_is_running(kdamond->damon_ctx); } =20 +static int damon_sysfs_set_threads_filter(struct damon_sample_filter *filt= er, + int *sysfs_tid_arr) +{ + int nr_tids, i; + pid_t *tid_arr; + + if (!sysfs_tid_arr) + return -EINVAL; + nr_tids =3D sysfs_tid_arr[0]; + tid_arr =3D kmalloc_array(nr_tids, sizeof(*tid_arr), GFP_KERNEL); + if (!tid_arr) + return -ENOMEM; + for (i =3D 0; i < nr_tids; i++) + tid_arr[i] =3D sysfs_tid_arr[i + 1]; + filter->tid_arr =3D tid_arr; + filter->nr_tids =3D nr_tids; + return 0; +} + static int damon_sysfs_set_sample_filters( struct damon_sample_control *control, struct damon_sysfs_sample_filters *sysfs_filters) @@ -1972,6 +2041,12 @@ static int damon_sysfs_set_sample_filters( case DAMON_FILTER_TYPE_CPUMASK: filter->cpumask =3D sysfs_filter->cpumask; break; + case DAMON_FILTER_TYPE_THREADS: + err =3D damon_sysfs_set_threads_filter(filter, + sysfs_filter->tid_arr); + if (err) + damon_free_sample_filter(filter); + break; default: break; } --=20 2.47.3