From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AE345371D05 for ; Fri, 29 May 2026 04:08:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780027707; cv=none; b=UWbiEeCJDH4VXz01YbLBj/WbnHrhTBUneOsDXEJ1x2LVxX6ZtLaGHa2uHEPbve+VpQ5mN+aqmqXmOUBl/KdnLc7I9K3+TqqqJtBY/I9sWWT8ronbTEo3zMgSNDWSCwe8IpMUMa5xzc9NI5SQBpGCNeKJEkdm99+kx7DCoKYcq/c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780027707; c=relaxed/simple; bh=c4q2LnrPwLgcN9k+BiewIQIj2+T973DdtYUSmeQBvYE=; h=Date:To:From:Subject:Message-Id; b=f9awfVw28+EhMf3Euo0a+QpB/2l32TD+RXHz1Oph15mYsM8EgmHvF1LvFldD8QK5RRAvNixjOEKzQxANMDJJnM9ldpBRmrh7j7j5X/A4E7kvqRcohOG8FcvM0h4fpnsQmIyi3ybYLQVEvIJWq1ldAJIumTuaGv+BbdNHXFjhjCs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=UeMbTaJC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="UeMbTaJC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 850771F00893; Fri, 29 May 2026 04:08:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1780027705; bh=CzTx+rE4nGmnj1CF230AZaoExPG7pQggppsFJ5jgMGU=; h=Date:To:From:Subject; b=UeMbTaJCmBP4EDM6YYraJEkW9dvhMcijytRuaTxZIUzvK33MhAAJnCQHviiZPgmmk 6/RQ7UqhnoXVqKC2PTWbdijJsoAoB/pWcyREd8TNaIzDE2pwBF2PX2R6/6ldAvNkCY d6px/ZFW7jy7K1Qo4tYx5f1xPrGjOyEqyPI6/hzk= Date: Thu, 28 May 2026 21:08:25 -0700 To: mm-commits@vger.kernel.org,vbabka@kernel.org,surenb@google.com,rppt@kernel.org,mhocko@suse.com,ljs@kernel.org,liam@infradead.org,david@kernel.org,corbet@lwn.net,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-damon-stat-add-a-parameter-for-reading-kdamond-pid.patch removed from -mm tree Message-Id: <20260529040825.850771F00893@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/damon/stat: add a parameter for reading kdamond pid has been removed from the -mm tree. Its filename was mm-damon-stat-add-a-parameter-for-reading-kdamond-pid.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: SeongJae Park Subject: mm/damon/stat: add a parameter for reading kdamond pid Date: Fri, 1 May 2026 19:05:03 -0700 Patch series "mm/damon/stat: add kdamond_pid parameter". DAMON_STAT doesn't provide the pid of its kdamond, unlike DAMON_RECLAIM and DAMON_LRU_SORT. This makes user-space management of DAMON_STAT unnecessarily complicated. Provide the information via a new parameter, namely kdamond_pid, and document it. This patch (of 2): Knowing the pid of the kdamonds can help user-space management including monitoring of DAMON's system resource consumption. To make it easier, DAMON_SYSFS, DAMON_RECLAIM and DAMON_LRU_SORT provide the pid information. DAMON_STAT is not providing it, though. Expose the pid of DAMON_STAT kdamond via a new read-only module parameter, namely kdamond_pid. This also makes DAMON modules usage more standardized, because DAMON_RECLAIM and DAMON_LRU_SORT also provide the information via their read-only parameters of the same name. Link: https://lore.kernel.org/20260502020505.80822-1-sj@kernel.org Link: https://lore.kernel.org/20260502020505.80822-2-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- mm/damon/stat.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) --- a/mm/damon/stat.c~mm-damon-stat-add-a-parameter-for-reading-kdamond-pid +++ a/mm/damon/stat.c @@ -266,6 +266,45 @@ static int damon_stat_enabled_load(char return sprintf(buffer, "%c\n", damon_stat_enabled() ? 'Y' : 'N'); } +static int damon_stat_kdamond_pid_store( + const char *val, const struct kernel_param *kp) +{ + /* + * kdamond_pid is read-only, but kernel command line could write it. + * Do nothing here. + */ + return 0; +} + +static int damon_stat_kdamond_pid_load( + char *buffer, const struct kernel_param *kp) +{ + int pid; + + if (!damon_stat_context) { + pid = -1; + } else { + pid = damon_kdamond_pid(damon_stat_context); + if (pid < 1) + pid = -1; + } + return sprintf(buffer, "%d\n", pid); +} + +static const struct kernel_param_ops kdamond_pid_param_ops = { + .set = damon_stat_kdamond_pid_store, + .get = damon_stat_kdamond_pid_load, +}; + +/* + * PID of the DAMON thread + * + * If DAMON_STAT is enabled, this becomes the PID of the worker thread. + * Else, -1. + */ +module_param_cb(kdamond_pid, &kdamond_pid_param_ops, NULL, 0400); +MODULE_PARM_DESC(kdamond_pid, "pid of the kdamond"); + static int __init damon_stat_init(void) { int err = 0; _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-ops-common-call-folio_test_lru-after-folio_get.patch mm-damon-reclaim-handle-ctx-allocation-failure.patch mm-damonn-lru_sort-handle-ctx-allocation-failure.patch mm-damon-core-introduce-struct-damon_probe.patch mm-damon-core-embed-damon_probe-objects-in-damon_ctx.patch mm-damon-core-introduce-damon_filter.patch mm-damon-core-commit-probes.patch mm-damon-core-introduce-damon_region-probe_hits.patch mm-damon-core-introduce-damon_ops-apply_probes.patch mm-damon-core-do-data-attributes-monitoring.patch mm-damon-paddr-support-data-attributes-monitoring.patch mm-damon-sysfs-implement-probes-dir.patch mm-damon-sysfs-implement-probe-dir.patch mm-damon-sysfs-implement-filters-directory.patch mm-damon-sysfs-implement-filter-dir.patch mm-damon-sysfs-implement-filter-dir-files.patch mm-damon-sysfs-setup-probes-on-damon-core-api-parameters.patch mm-damon-sysfs-schemes-implement-tried_regions-r-probes.patch mm-damon-sysfs-schemes-implement-probe-dir.patch mm-damon-sysfs-schemes-implement-probe-hits-file.patch mm-damon-trace-probe_hits.patch selftests-damon-sysfssh-test-probes-dir.patch docs-mm-damon-design-document-data-attributes-monitoring.patch docs-admin-guide-mm-damon-usage-document-data-attributes-monitoring.patch mm-damon-core-introduce-damon_filter_type_memcg.patch mm-damon-paddr-support-damon_filter_type_memcg.patch mm-damon-sysfs-add-filters-f-path-file.patch mm-damon-sysfs-schemes-move-memcg_path_to_id-to-sysfs-common.patch mm-damon-sysfs-setup-damon_filter-memcg_id-from-path.patch docs-mm-damon-design-update-for-memcg-damon-filter.patch docs-admin-guide-mm-damon-usage-update-for-memcg-damon-filter.patch mm-damon-core-safely-handle-no-region-case-in-damon_set_regions.patch mm-damon-core-do-not-use-region-out-of-a-loop-in-damon_set_regions.patch samples-damon-mtier-replace-damon_add_region-with-damon_set_regions.patch mm-damon-tests-vaddr-kunit-replace-damon_add_region-with-damon_set_regions.patch mm-damon-core-hide-damon_add_region.patch mm-damon-core-hide-damon_insert_region.patch mm-damon-core-hide-damon_destroy_region.patch mm-damon-core-add-kdamond_call-debug_sanity-check.patch mm-damon-core-remove-damon_verify_nr_regions.patch mm-damon-tests-core-kunit-add-damon_set_regions-test-cases.patch selftests-damon-sysfspy-stop-kdamonds-before-failing.patch selftests-damon-sysfssh-test-monitoring-intervals-goal-dir.patch selftests-damon-sysfssh-test-addr_unit-file-existence.patch selftests-damon-sysfssh-test-pause-file-existence.patch mm-damon-core-trace-esz-at-first-setup.patch