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 25ECC33EB06; Sat, 16 May 2026 18:37:28 +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=1778956648; cv=none; b=rJyGy94l/DVR8AaJqJQiUBXzuOhoyFZrnqzc5D2E/bAVZGvoCXcqK7PU4ysUrqv5WTg1IpKjRaYZ36kn47RxavV8Do0slmHiVeRPMRtBPT11er22r6t7nfUkq5XEdrpl4JmbzGQbRb8Up8gTxptXbzRU2UDtIU56IrsycVaoGQI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778956648; c=relaxed/simple; bh=WYmv4bT5UJuMRx71xod34Pd0amao4jaLlWchqRhE7dM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=S1PcuTUVz+HDY0ZxYRDYCcot40G6bTfg+/C335pnXxYKSttqHKBrIJJNemBnWK3SCpI94CfQpnKnGF8JAGafODi23YqXCdRjn8qiyRt1aQcBDS5wkxh8EyWAzCx3uAMIRcJ17XiWF5z2miy7D0U4c7THDaaK/uls/2QaaEjviss= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HBfjDveL; 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="HBfjDveL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0978C2BCFA; Sat, 16 May 2026 18:37:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778956648; bh=WYmv4bT5UJuMRx71xod34Pd0amao4jaLlWchqRhE7dM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HBfjDveL8mJyDYDZQuy4FgIoTDXLxwDdX5RmY7qfHqZoBxBzUHtf3nZOwe21OGScB InS3vc5L9fBnSomAQv8on8fE1SM0rR91V0xK7x6qOyzry1/PYlLqYODNiU3OmeL8ib aAW0Ulbt9+GmatqlMsGFcArr10vc9v4FSHXWZ4JN0OIwtZYOxSw6jEKhTNf20inOyg O+WO5KiOpFeD4/uQ40QPZ6o+vLKlK1RWHJeHTXloJAIe9TwJRpOVMY0oZMAq6EeKS1 NBNYagYVkW0rZAc8gL1GdIudnWqgEMcQxaYtAcdUBMBgyz7H8p7cLHgX8ch5szRQZI 6QmgayJqrIvuQ== 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 10/28] mm/damon/sysfs: implement probe dir Date: Sat, 16 May 2026 11:36:51 -0700 Message-ID: <20260516183712.81393-11-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260516183712.81393-1-sj@kernel.org> References: <20260516183712.81393-1-sj@kernel.org> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Implement sysfs directory for letting users install each data probe. Signed-off-by: SeongJae Park --- mm/damon/sysfs.c | 119 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 119 insertions(+) diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 5f3b253f50ebf..162d2d55be08e 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -747,12 +747,43 @@ static const struct kobj_type damon_sysfs_intervals_ktype = { .default_groups = damon_sysfs_intervals_groups, }; +/* + * probe directory + */ + +struct damon_sysfs_probe { + struct kobject kobj; +}; + +static struct damon_sysfs_probe *damon_sysfs_probe_alloc(void) +{ + return kzalloc_obj(struct damon_sysfs_probe); +} + +static void damon_sysfs_probe_release(struct kobject *kobj) +{ + kfree(container_of(kobj, struct damon_sysfs_probe, kobj)); +} + +static struct attribute *damon_sysfs_probe_attrs[] = { + NULL, +}; +ATTRIBUTE_GROUPS(damon_sysfs_probe); + +static const struct kobj_type damon_sysfs_probe_ktype = { + .release = damon_sysfs_probe_release, + .sysfs_ops = &kobj_sysfs_ops, + .default_groups = damon_sysfs_probe_groups, +}; + /* * probes directory */ struct damon_sysfs_probes { struct kobject kobj; + struct damon_sysfs_probe **probes_arr; + int nr; }; static struct damon_sysfs_probes *damon_sysfs_probes_alloc(void) @@ -760,12 +791,99 @@ static struct damon_sysfs_probes *damon_sysfs_probes_alloc(void) return kzalloc_obj(struct damon_sysfs_probes); } +static void damon_sysfs_probes_rm_dirs( + struct damon_sysfs_probes *probes) +{ + struct damon_sysfs_probe **probes_arr = probes->probes_arr; + int i; + + for (i = 0; i < probes->nr; i++) + kobject_put(&probes_arr[i]->kobj); + probes->nr = 0; + kfree(probes_arr); + probes->probes_arr = NULL; +} + +static int damon_sysfs_probes_add_dirs( + struct damon_sysfs_probes *probes, int nr_probes) +{ + struct damon_sysfs_probe **probes_arr, *probe; + int err, i; + + damon_sysfs_probes_rm_dirs(probes); + if (!nr_probes) + return 0; + + probes_arr = kmalloc_objs(*probes_arr, nr_probes, + GFP_KERNEL | __GFP_NOWARN); + if (!probes_arr) + return -ENOMEM; + probes->probes_arr = probes_arr; + + for (i = 0; i < nr_probes; i++) { + probe = damon_sysfs_probe_alloc(); + if (!probe) { + damon_sysfs_probes_rm_dirs(probes); + return -ENOMEM; + } + + err = kobject_init_and_add(&probe->kobj, + &damon_sysfs_probe_ktype, &probes->kobj, + "%d", i); + if (err) { + kobject_put(&probe->kobj); + damon_sysfs_probes_rm_dirs(probes); + return err; + } + + probes_arr[i] = probe; + probes->nr++; + } + return 0; +} + +static ssize_t nr_probes_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_probes *probes = container_of(kobj, + struct damon_sysfs_probes, kobj); + + return sysfs_emit(buf, "%d\n", probes->nr); +} + +static ssize_t nr_probes_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, size_t count) +{ + struct damon_sysfs_probes *probes; + int nr, err = kstrtoint(buf, 0, &nr); + + if (err) + return err; + if (nr < 0 || nr > DAMON_MAX_PROBES) + return -EINVAL; + + probes = container_of(kobj, struct damon_sysfs_probes, kobj); + + if (!mutex_trylock(&damon_sysfs_lock)) + return -EBUSY; + err = damon_sysfs_probes_add_dirs(probes, nr); + mutex_unlock(&damon_sysfs_lock); + if (err) + return err; + + return count; +} + static void damon_sysfs_probes_release(struct kobject *kobj) { kfree(container_of(kobj, struct damon_sysfs_probes, kobj)); } +static struct kobj_attribute damon_sysfs_probes_nr_probes = + __ATTR_RW_MODE(nr_probes, 0600); + static struct attribute *damon_sysfs_probes_attrs[] = { + &damon_sysfs_probes_nr_probes.attr, NULL, }; ATTRIBUTE_GROUPS(damon_sysfs_probes); @@ -862,6 +980,7 @@ static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs) kobject_put(&attrs->nr_regions_range->kobj); damon_sysfs_intervals_rm_dirs(attrs->intervals); kobject_put(&attrs->intervals->kobj); + damon_sysfs_probes_rm_dirs(attrs->probes); kobject_put(&attrs->probes->kobj); } -- 2.47.3