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 31A8A85C4A for ; Tue, 16 Sep 2025 04:01:05 +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=1757995266; cv=none; b=o5vp1ljrVEnjqiRZRguADKXi7/raxvJgnX/BXDWSu0oonT6xA3MztppjUPQwkWZbrpZ3KHA62o6htJNI16VyFrft2wtl/nIkaj1SxOgY6RqfpRHTLM9+hfOz+xagGFVB6XrcHbcr8D3oeAb65KO1OlYcRHDcv5PaJgX7/lzzWkg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757995266; c=relaxed/simple; bh=zuXwIqVaqtUV0hxiwT/5zYQN51Ytzcjkwk+BVp/elTY=; h=Date:To:From:Subject:Message-Id; b=RpqJ2oVQbRNXPQwlaXqqKT3lTet7OTrPYn9kKgWzt9rLMgNSVxuYFLA+f+pBZupDjCiNBRKbUxGP4DJBbpbf4siADSFRi18950CGYyA56AVHZcano0othWm4nIY7APlsSiaTXjYtLnaXuva2Jy0TFGgagYFyDyeYUBTFzl8o1vs= 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=bNtBVCvB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="bNtBVCvB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 933AEC4CEEB; Tue, 16 Sep 2025 04:01:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1757995265; bh=zuXwIqVaqtUV0hxiwT/5zYQN51Ytzcjkwk+BVp/elTY=; h=Date:To:From:Subject:From; b=bNtBVCvBLSjc1Bj+qWtW7VhqfkF/ETHV//ky5WTFIimtBuSxsUwWIFwYhD4aBZrhJ W68bj1Yxxvq1Yrygf0GQSCYekfVX/qBvGbadLv6n6MfdVAEM0Z1066QdvWTnJM0GMA HBGZq69v8+lYqOnaqvQBNgFLW2FAY0W/fveMAX/U= Date: Mon, 15 Sep 2025 21:01:05 -0700 To: mm-commits@vger.kernel.org,vbabka@suse.cz,surenb@google.com,rppt@kernel.org,mhocko@suse.com,lorenzo.stoakes@oracle.com,liam.howlett@oracle.com,joshua.hahnjy@gmail.com,david@redhat.com,corbet@lwn.net,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-damon-core-reset-age-if-nr_accesses-changes-between-non-zero-and-zero.patch added to mm-new branch Message-Id: <20250916040105.933AEC4CEEB@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: reset age if nr_accesses changes between non-zero and zero has been added to the -mm mm-new branch. Its filename is mm-damon-core-reset-age-if-nr_accesses-changes-between-non-zero-and-zero.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-reset-age-if-nr_accesses-changes-between-non-zero-and-zero.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. 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/core: reset age if nr_accesses changes between non-zero and zero Date: Sun, 14 Sep 2025 18:58:02 -0700 Misc fixes and improvements for DAMON that are not critical and therefore aims to be merged into Linux 6.18-rc1. The first patch improves DAMON's age counting for nr_accesses zero to/from non-zero changes. The second patch fixes an initial DAMOS apply interval delay issue that is not realistic but still could happen on an odd setup. The third patch fixes wrongly written code that doesn't cause any real problem but could make code review confusing. The fourth and the fifth patches update DAMON community meetup description and DAMON user-space tool example command for DAMOS usage, respectively. Finally, the sixth patch updates MAINTAINERS section name for DAMON to just DAMON. This patch (of 6): DAMON resets the age of a region if its nr_accesses value has significantly changed. Specifically, the threshold is calculated as 20% of largest nr_accesses of the current snapshot. This means that regions changing the nr_accesses from zero to small non-zero value or from a small non-zero value to zero will keep the age. Since many users treat zero nr_accesses regions special, this can be confusing. Kernel code including DAMOS' regions priority calculation and DAMON_STAT's idle time calculation also treat zero nr_accesses regions special. Make it unconfusing by resetting the age when the nr_accesses changes between zero and a non-zero value. Link: https://lkml.kernel.org/r/20250915015807.101505-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250915015807.101505-2-sj@kernel.org Signed-off-by: SeongJae Park Reviewed-by: Joshua Hahn Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam 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 | 3 +++ 1 file changed, 3 insertions(+) --- a/mm/damon/core.c~mm-damon-core-reset-age-if-nr_accesses-changes-between-non-zero-and-zero +++ a/mm/damon/core.c @@ -2261,6 +2261,9 @@ static void damon_merge_regions_of(struc damon_for_each_region_safe(r, next, t) { if (abs(r->nr_accesses - r->last_nr_accesses) > thres) r->age = 0; + else if ((!r->nr_accesses && r->last_nr_accesses) || + (r->nr_accesses && !r->last_nr_accesses)) + r->age = 0; else r->age++; _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-core-reset-age-if-nr_accesses-changes-between-non-zero-and-zero.patch mm-damon-core-set-effective-quota-on-first-charge-window.patch mm-damon-lru_sort-use-param_ctx-correctly.patch docs-mm-damon-maintainer-profile-update-community-meetup-for-reservation-requirements.patch docs-admin-guide-mm-damon-start-add-target_pid-to-damos-example-command.patch maintainers-rename-damon-section.patch