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 20C7C39AD3A for ; Fri, 10 Jul 2026 20:24:06 +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=1783715048; cv=none; b=XDxDxUCEf7YuW2LmfeMQJ+M3HOqrV5SqgkPel8eMgms+gycdmofz0oYGK0CgGk9SJelLA07axZ5bt9N7CRCzNaVi4Qt/47i7LD/KLLr+qR5wmJwIoTg3tcebIKpxhkisz1tYttwsZJszDWLQD2QddFQTe7X6gZlPCLvm0UjdD9M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783715048; c=relaxed/simple; bh=EzcrGoEQdNXSTQHYrHPNrC6poFJ6/v18gjsYJT96ymo=; h=Date:To:From:Subject:Message-Id; b=rbrR0OJaf5uEU0EgUNmzveu1+n4ezlYDwebJMkDijHisP3XhsLTJ2iPmFa7R+yBtCO90kHQUBdZX6b1SgwxeesCKXeyfHeQRFTiBvm6fv87bMpNqwDjnVy0yABHAOuB9DhzFzqQS7wdh5mhdwBEa0tUJLvahujtaGku4XHd1Jvg= 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=ESFEqC8l; 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="ESFEqC8l" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E74D21F00ACA; Fri, 10 Jul 2026 20:24:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1783715046; bh=sno1TtiUhbAkvULKhjAbj/1n9jgqG/uD5wRmG7CrBus=; h=Date:To:From:Subject; b=ESFEqC8lFMZ/DfIQvRVbv4KUdoV18MW2HilB2xfJY2RAklTBXmu9TgoD5WA0C58EP 7tQEOMCACsCTsniYC19XqIChS9NF9bLIg61hyitI51ObSew50MokI3qCSCNBAyHUGZ tKIti9gR6j8tfGaTEjEYnhsQG6twOf1VKKT1NIw4= Date: Fri, 10 Jul 2026 13:24:05 -0700 To: mm-commits@vger.kernel.org,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-damon-core-extend-merge-function-to-work-with-probe-hits.patch added to mm-new branch Message-Id: <20260710202405.E74D21F00ACA@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/damon/core: extend merge function to work with probe hits has been added to the -mm mm-new branch. Its filename is mm-damon-core-extend-merge-function-to-work-with-probe-hits.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-extend-merge-function-to-work-with-probe-hits.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next 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 various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: SJ Park Subject: mm/damon/core: extend merge function to work with probe hits Date: Fri, 10 Jul 2026 06:46:37 -0700 When probe weights are set, users may want DAMON monitoring results to be optimized for the weights. For that, regions adjustment should work for the weighted sum of probe hits. Extend damon_merge_regions_of() to detect if the weights are set, and work with probe hits in the case. The weights setup detection function is incomplete. It always returns false. It is intentional, so that more changes to completely support weights can be made in an incremental but safe way. Until the function is completed, all changes depend on it is no-op, so DAMON works in the current mode. Link: https://lore.kernel.org/20260710134651.18084-9-sj@kernel.org Signed-off-by: SJ 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/core.c | 49 +++++++++++++++++++++++++++------- mm/damon/tests/core-kunit.h | 13 +++++++-- 2 files changed, 50 insertions(+), 12 deletions(-) --- a/mm/damon/core.c~mm-damon-core-extend-merge-function-to-work-with-probe-hits +++ a/mm/damon/core.c @@ -209,6 +209,11 @@ static struct damon_probe *damon_nth_pro return NULL; } +static bool damon_has_probe_weights(struct damon_ctx *c) +{ + return false; +} + /* * damon_mvsum() - Returns pseudo moving sum value for a time window. * @current_nr: The value of the current aggregation window. @@ -3248,6 +3253,16 @@ static void damon_merge_two_regions(stru damon_destroy_region(r, t); } +static unsigned int damon_merge_score(struct damon_region *r, bool last, + struct damon_ctx *ctx, bool use_probe_hits) +{ + if (use_probe_hits) + return damon_probe_hits_wsum(r, last, ctx); + if (last) + return r->last_nr_accesses; + return r->nr_accesses; +} + /* * Merge adjacent regions having similar access frequencies * @@ -3256,24 +3271,38 @@ static void damon_merge_two_regions(stru * sz_limit size upper limit of each region */ static void damon_merge_regions_of(struct damon_target *t, unsigned int thres, - unsigned long sz_limit) + unsigned long sz_limit, struct damon_ctx *ctx) { struct damon_region *r, *prev = NULL, *next; + bool use_probe_hits = damon_has_probe_weights(ctx); damon_for_each_region_safe(r, next, t) { - if (abs_diff(r->nr_accesses, r->last_nr_accesses) > thres) + unsigned int score, last_score, diff; + + score = damon_merge_score(r, false, ctx, use_probe_hits); + last_score = damon_merge_score(r, true, ctx, use_probe_hits); + + if (abs_diff(score, last_score) > thres) r->age = 0; - else if ((r->nr_accesses == 0) != (r->last_nr_accesses == 0)) + else if ((score == 0) != (last_score == 0)) r->age = 0; else r->age++; - if (prev && prev->ar.end == r->ar.start && - abs_diff(prev->nr_accesses, r->nr_accesses) <= thres && - damon_sz_region(prev) + damon_sz_region(r) <= sz_limit) - damon_merge_two_regions(t, prev, r); - else - prev = r; + if (!prev) + goto set_prev_continue; + if (prev->ar.end != r->ar.start) + goto set_prev_continue; + diff = abs_diff(score, damon_merge_score(prev, false, ctx, + use_probe_hits)); + if (diff > thres) + goto set_prev_continue; + if (damon_sz_region(prev) + damon_sz_region(r) > sz_limit) + goto set_prev_continue; + damon_merge_two_regions(t, prev, r); + continue; +set_prev_continue: + prev = r; } } @@ -3306,7 +3335,7 @@ static void kdamond_merge_regions(struct do { nr_regions = 0; damon_for_each_target(t, c) { - damon_merge_regions_of(t, threshold, sz_limit); + damon_merge_regions_of(t, threshold, sz_limit, c); nr_regions += damon_nr_regions(t); } threshold = max(1, threshold * 2); --- a/mm/damon/tests/core-kunit.h~mm-damon-core-extend-merge-function-to-work-with-probe-hits +++ a/mm/damon/tests/core-kunit.h @@ -226,6 +226,7 @@ static struct damon_region *__nth_region static void damon_test_merge_regions_of(struct kunit *test) { + struct damon_ctx *ctx; struct damon_target *t; struct damon_region *r; unsigned long sa[] = {0, 100, 114, 122, 130, 156, 170, 184, 230}; @@ -236,20 +237,27 @@ static void damon_test_merge_regions_of( unsigned long eaddrs[] = {112, 130, 156, 170, 230, 10170}; int i; + ctx = damon_new_ctx(); + if (!ctx) + kunit_skip(test, "ctx alloc fail"); + t = damon_new_target(); - if (!t) + if (!t) { + damon_destroy_ctx(ctx); kunit_skip(test, "target alloc fail"); + } for (i = 0; i < ARRAY_SIZE(sa); i++) { r = damon_new_region(sa[i], ea[i]); if (!r) { damon_free_target(t); + damon_destroy_ctx(ctx); kunit_skip(test, "region alloc fail"); } r->nr_accesses = nrs[i]; damon_add_region(r, t); } - damon_merge_regions_of(t, 9, 9999); + damon_merge_regions_of(t, 9, 9999, ctx); /* 0-112, 114-130, 130-156, 156-170, 170-230, 230-10170 */ KUNIT_EXPECT_EQ(test, damon_nr_regions(t), 6u); for (i = 0; i < 6; i++) { @@ -258,6 +266,7 @@ static void damon_test_merge_regions_of( KUNIT_EXPECT_EQ(test, r->ar.end, eaddrs[i]); } damon_free_target(t); + damon_destroy_ctx(ctx); } static void damon_test_split_regions_of(struct kunit *test) _ Patches currently in -mm which might be from sj@kernel.org are samples-damon-wsse-handle-damon_start-failure.patch samples-damon-prcl-handle-damon_start-failure.patch samples-damon-mtier-handle-damon_start-failure.patch samples-damon-mtier-handle-damon_stop-failure.patch samples-damon-wsse-stop-and-free-damon-ctx-when-damon_call-fails.patch samples-damon-prcl-stop-and-free-damon-ctx-when-damon_call-fails.patch mm-damon-sysfs-kobject_del-target-normal-context-and-kdamond-dirs.patch mm-damon-sysfs-kobject_del-region-and-target-error-dirs.patch mm-damon-sysfs-schemes-kobject_del-scheme-dirs.patch mm-damon-sysfs-schemes-kobject_del-scheme-region-dirs.patch mm-damon-sysfs-schemes-kobject_del-scheme-filter-dirs.patch mm-damon-sysfs-schemes-kobject_del-scheme-quota-goal-dirs.patch mm-damon-sysfs-schemes-kobject_del-scheme-action-destination-dirs.patch mm-damon-sysfs-kobject_del-probe-dirs.patch mm-damon-sysfs-kobject_del-probe-filter-dirs.patch mm-damon-sysfs-kobject_del-probe-dirs-in-probes_addd_dir-error-path.patch mm-damon-sysfs-schemes-kobject_del-region-for-populate_region-error.patch docs-mm-damon-design-update-for-damos_quota_node_eligible_mem_bp.patch docs-abi-damon-document-probe-files.patch mm-damon-tests-core-kunit-test-damon_rand.patch selftests-damon-sysfssh-test-multiple-probe-dirs-creation.patch selftests-damon-sysfssh-test-coreops_filters-directories.patch selftests-damon-sysfssh-test-dests-dir.patch selftests-damon-sysfssh-test-all-files-in-quota-goal-dir.patch mm-damon-core-reduce-range-setup-in-damon_commit_target_regions.patch mm-damon-sysfs-split-probe-setup-function-out.patch mm-damon-sysfs-split-out-filters-setup-function.patch mm-damon-sysfs-fix-typos-in-probe_addrm_dirs-s-attr-probe.patch mm-damon-core-introduce-damon_nr_accesses_mvsum.patch mm-damon-tests-core-kunit-test-damon_mvsum.patch mm-damon-core-always-update-last_nr_accesses-for-intervals-change.patch mm-damon-core-handle-unreset-nr_accesses-in-damon_nr_accesses_mvsum.patch mm-damon-core-use-damon_nr_accesses_mvsum-in-__damos_valid_target.patch mm-damon-core-use-damon_nr_accesses_mvsum-for-damos-region-tracing.patch mm-damon-sysfs-schemes-use-damon_nr_accesses_mvsum-for-damo-regions.patch mm-damon-core-remove-damon_warn_fix_nr_accesses_corruption.patch mm-damon-core-remove-damon_verify_reset_aggregated.patch mm-damon-core-remove-damon_verify_merge_regions_of.patch mm-damon-tests-core-kunit-remove-nr_accesses_bp-setup-and-tests.patch selftests-damon-drgn_dump_damon_status-do-not-dump-nr_accesses_bp.patch mm-damon-core-remove-nr_accesses_bp-setups-and-updates.patch mm-damon-core-remove-attrs-param-from-damon_update_region_access_rate.patch mm-damon-paddr-remove-attrs-param-from-__damon_pa_check_access.patch mm-damon-vaddr-remove-attrs-param-from-__damon_va_check_access.patch mm-damon-core-remove-damon_moving_sum-and-its-unit-test.patch mm-damon-core-remove-damon_region-nr_accesses_bp.patch mm-damon-add-damon_region-last_probe_hits.patch mm-damon-core-introduce-damon_probe_hits_mvsum.patch mm-damon-sysfs-schemes-set-probe-hits-as-pseudo-moving-sums.patch mm-damon-core-safely-validate-src-on-damon_commit_ctx.patch mm-damon-core-do-parameter-testing-commit-on-damon_start.patch mm-damon-sysfs-remove-duplicated-commit-input-validity-check.patch mm-damon-reclaim-remove-duplicated-min_region_sz-power-of-2-check.patch mm-damon-lru_sort-remove-duplicated-min_region_sz-power_of_2-check.patch mm-damon-document-region-size-validation-in-damon_set_regions.patch mm-damon-core-remove-start-end-check-in-damon_set_region_system_rams.patch mm-damon-sysfs-remove-region-size-validation.patch mm-damon-core-stop-ctxs-in-damon_start-before-returning-an-error.patch samples-damon-mtier-do-not-stop-first-context-for-damon_start-failure.patch mm-damon-core-make-damon_stop-never-fails.patch mm-damon-sysfs-ignore-damon_stop-return-value.patch mm-damon-reclaaim-ignore-damon_stop-return-value.patch mm-damon-lru_sort-ignore-damon_stop-return-value.patch mm-damon-core-change-damon_stop-return-type-to-void.patch samples-damon-mtier-stop-all-contexts-with-single-damon_stop-call.patch mm-damon-core-wait-ctx-stop-in-damon_call-before-reruning-an-error.patch samples-damon-wsse-do-not-stop-ctx-for-damon_call-failure.patch samples-damon-prcl-do-not-stop-damon-for-damon_call-failure.patch mm-damon-core-remove-comment-and-test-for-nr_to_bp-divide-by-zero.patch mm-damon-core-s-damon_max_nr_accesses-damon_nr_samples_per_aggr.patch mm-damon-core-s-accesses_bp_to_nr_accesses-sample_bp_to_count.patch mm-damon-core-s-nr_accesses_to_accesses_bp-sample_count_to_bp.patch mm-damon-core-s-nr_accesses_for_new_attrs-nr_samples_for_new_attrs.patch mm-damon-core-update-probe-hits-for-new-parameter-commit.patch mm-damon-core-handle-unreset-probe_hits-in-probe_hits_mvsum.patch mm-damon-core-introduce-damon_probe-weight.patch mm-damon-core-ask-apply_probes-ops-callback-to-set-sampling-address.patch mm-damon-paddr-set-samples-in-apply_probes-if-requested.patch mm-damon-core-ask-apply_probe-to-return-max-probe-hits-weighted-sum.patch mm-damon-core-implement-damon_probe_hits_wsum.patch mm-damon-paddr-respect-return_max_wsum.patch mm-damon-core-use-abs_diff-instead-of-abs.patch mm-damon-core-extend-merge-function-to-work-with-probe-hits.patch mm-damon-core-disallow-probe_hits-overflow-on-attrs-only-monitoring.patch mm-damon-core-validate-params-for-probe-hits-weighted-sum-overflow.patch mm-damon-core-disable-access-monitoring-when-probe-weights-are-set.patch mm-damon-core-set-samples-in-apply_probes-if-probe-weights-are-set.patch mm-damon-core-s-max_nr_accesses-max_merge_score-in-kdamond_fn.patch mm-damon-core-get-merge-threshold-from-probe-hits-when-weights-are-set.patch mm-damon-core-implement-damon_has_probe_weight.patch mm-damon-sysfs-implement-probe-weight-file.patch docs-mm-damon-design-document-attrs-only-monitoring.patch docs-admin-guide-mm-damon-usage-document-weight-sysfs-file.patch docs-abi-damon-document-probe-weight-file.patch