From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2C36EC00528 for ; Wed, 2 Aug 2023 21:47:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233722AbjHBVro (ORCPT ); Wed, 2 Aug 2023 17:47:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44284 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231238AbjHBVrW (ORCPT ); Wed, 2 Aug 2023 17:47:22 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B14603C02 for ; Wed, 2 Aug 2023 14:46:43 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4B25061B32 for ; Wed, 2 Aug 2023 21:46:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9DA75C433C8; Wed, 2 Aug 2023 21:46:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1691012802; bh=+su7Qe6tnt0xk4Ylddy0ll0n6lVUgqrreYNP5TkPjSg=; h=Date:To:From:Subject:From; b=ImvNEoE04TT9WGOLXUVdzfNJ6/0w0CRRUAaCozGf03k2LpP95wIypY7IjL1bQqM9z d1LlBFyA0uygb7lyGKR+pATi2augin2oSCwTCC93Iqmr4WIE7qWm3wXrRHiVrqcQjo ghKcT7If1DiadPFuS/d+Z/QUTsQIfWZqEVTXYXP4= Date: Wed, 02 Aug 2023 14:46:41 -0700 To: mm-commits@vger.kernel.org, shuah@kernel.org, corbet@lwn.net, sj@kernel.org, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-damon-sysfs-schemes-implement-damos-tried-total-bytes-file.patch added to mm-unstable branch Message-Id: <20230802214642.9DA75C433C8@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/damon/sysfs-schemes: implement DAMOS tried total bytes file has been added to the -mm mm-unstable branch. Its filename is mm-damon-sysfs-schemes-implement-damos-tried-total-bytes-file.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-sysfs-schemes-implement-damos-tried-total-bytes-file.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: SeongJae Park Subject: mm/damon/sysfs-schemes: implement DAMOS tried total bytes file Date: Wed, 2 Aug 2023 21:32:17 +0000 Patch series "mm/damon/sysfs-schemes: implement DAMOS tried total bytes file". The tried_regions directory of DAMON sysfs interface is useful for retrieving monitoring results snapshot or DAMOS debugging. However, for common use case that need to monitor only the total size of the scheme tried regions (e.g., monitoring working set size), the kernel overhead for directory construction and user overhead for reading the content could be high if the number of monitoring region is not small. This patchset implements DAMON sysfs files for efficient support of the use case. The first patch implements the sysfs file to reduce the user space overhead, and the second patch implements a command for reducing the kernel space overhead. The third patch adds a selftest for the new file, and following two patches update documents. [1] https://lore.kernel.org/damon/20230728201817.70602-1-sj@kernel.org/ This patch (of 5): The tried_regions directory can be used for retrieving the monitoring results snapshot for regions of specific access pattern, by setting the scheme's action as 'stat' and the access pattern as required. While the interface provides every detail of the monitoring results, some use cases including working set size monitoring requires only the total size of the regions. For such cases, users should read all the information and calculate the total size of the regions. However, it could incur high overhead if the number of regions is high. Add a file for retrieving only the information, namely 'total_bytes' file. It allows users to get the total size by reading only the file. Link: https://lkml.kernel.org/r/20230802213222.109841-1-sj@kernel.org Link: https://lkml.kernel.org/r/20230802213222.109841-2-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Cc: Shuah Khan Signed-off-by: Andrew Morton --- mm/damon/sysfs-schemes.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) --- a/mm/damon/sysfs-schemes.c~mm-damon-sysfs-schemes-implement-damos-tried-total-bytes-file +++ a/mm/damon/sysfs-schemes.c @@ -117,6 +117,7 @@ struct damon_sysfs_scheme_regions { struct kobject kobj; struct list_head regions_list; int nr_regions; + unsigned long total_bytes; }; static struct damon_sysfs_scheme_regions * @@ -128,9 +129,19 @@ damon_sysfs_scheme_regions_alloc(void) regions->kobj = (struct kobject){}; INIT_LIST_HEAD(®ions->regions_list); regions->nr_regions = 0; + regions->total_bytes = 0; return regions; } +static ssize_t total_bytes_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct damon_sysfs_scheme_regions *regions = container_of(kobj, + struct damon_sysfs_scheme_regions, kobj); + + return sysfs_emit(buf, "%lu\n", regions->total_bytes); +} + static void damon_sysfs_scheme_regions_rm_dirs( struct damon_sysfs_scheme_regions *regions) { @@ -148,7 +159,11 @@ static void damon_sysfs_scheme_regions_r kfree(container_of(kobj, struct damon_sysfs_scheme_regions, kobj)); } +static struct kobj_attribute damon_sysfs_scheme_regions_total_bytes_attr = + __ATTR_RO_MODE(total_bytes, 0400); + static struct attribute *damon_sysfs_scheme_regions_attrs[] = { + &damon_sysfs_scheme_regions_total_bytes_attr.attr, NULL, }; ATTRIBUTE_GROUPS(damon_sysfs_scheme_regions); @@ -1648,6 +1663,7 @@ static int damon_sysfs_before_damos_appl return 0; sysfs_regions = sysfs_schemes->schemes_arr[schemes_idx]->tried_regions; + sysfs_regions->total_bytes += r->ar.end - r->ar.start; region = damon_sysfs_scheme_region_alloc(r); list_add_tail(®ion->list, &sysfs_regions->regions_list); sysfs_regions->nr_regions++; @@ -1678,6 +1694,7 @@ int damon_sysfs_schemes_clear_regions( sysfs_scheme = sysfs_schemes->schemes_arr[schemes_idx++]; damon_sysfs_scheme_regions_rm_dirs( sysfs_scheme->tried_regions); + sysfs_scheme->tried_regions->total_bytes = 0; } return 0; } _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-core-initialize-damo_filter-list-from-damos_new_filter.patch mm-damon-core-test-add-a-test-for-damos_new_filter.patch mm-damon-sysfs-schemes-implement-damos-tried-total-bytes-file.patch mm-damon-sysfs-implement-a-command-for-updating-only-schemes-tried-total-bytes.patch selftests-damon-sysfs-test-tried_regions-total_bytes-file.patch docs-abi-damon-update-for-tried_regions-total_bytes.patch docs-admin-guide-mm-damon-usage-update-for-tried_regions-total_bytes.patch