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 801573BFAD3; Tue, 12 May 2026 14:37:01 +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=1778596621; cv=none; b=GRIiP69asSNyz2Xft1Q6x4aYxDqHQl2w5GRnkKKp0yxehWPtZrvlne3JoF/eVEb5qTvXWP4La5lQ/smEi/xoWSIAobTdtogT4nN4ITajCmaVYSKQuhPzIaU+h3VzETgVMuPc7gBIYoAcsogorVCi66FXxgBbGIRtUKhCT9oWbx4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778596621; c=relaxed/simple; bh=SZZB/8Y34d4c5OpPrN0Tt1+a+YDiqj7LFYZQ5Lka3iE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uO8mmGAFVpcsyQ4pcLe9vdoKwILEmlDbaOnECCSnBdseJwmKMPCHc/pLDeVe0JlsD2SbHgDItqsLhzirdqzKhEHM6jQuCl1jO6lF9On+A0ptB7sZfEEHbCMyXJkcXduj7EGpiJHzwfYRYniRN2Sr9yuHL2gbqmF/ybndMhPcaEI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Y0sv3yot; 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="Y0sv3yot" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E078C2BCF6; Tue, 12 May 2026 14:37:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778596621; bh=SZZB/8Y34d4c5OpPrN0Tt1+a+YDiqj7LFYZQ5Lka3iE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y0sv3yotRwx8KtFM5xZjeSoYNFJ9drE6c6th8ir9S7Hu8QUHVRSv3C8r2Oxn+YvHN zg8+3L3byobrA6gvR/9ueyY5xOnJafXXNmAaDlSF2cGWkhaiq6SH6atl1yP0BD8pmA oSNNrVmA2BDyo0ZHfLqCTabMFwxmRyVS/TDQWIfP4AovGDX3m/U81OhKmGaNUdN73l oRNUHQG7ziEGukWVB6egNVPlp5ZY2/oKMMYx5XmQzbUf8ogdvTK58Swefojd5z3a8c Se2OwcYPYYDNwxw3rQg0QVMZb5EQp8eCH6SdkDEqXQADPaJHd8q+9swl98yNVQNwQM Fpxm3Gxti3xnw== 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 v2 10/28] mm/damon/sysfs: implement probe dir Date: Tue, 12 May 2026 07:36:25 -0700 Message-ID: <20260512143645.113201-11-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260512143645.113201-1-sj@kernel.org> References: <20260512143645.113201-1-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: 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 ccd19fc062f31..fac4e37aa2851 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); + +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