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 17CA533F599 for ; Sun, 28 Jun 2026 20:07:08 +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=1782677230; cv=none; b=N+j3DclEpiKr0UouEULrQ8bxq6YAwNpf6+4koAW6mVgh+2Ezs0B/dqEtyIFHqxDhPtMY/bnbJtqqJ1RfYKEQFFVSA313woaZaD/5+afBoDBbheD81oUizlFkYgv+eeCRk6ZibLh941n7G77G91mDGSLB+PV0TK+YI3E/9AloUuc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782677230; c=relaxed/simple; bh=6zOGGeUK8Xd95VrPDHJL3Fn8QUHp3I4o5KILFADOjQg=; h=Date:To:From:Subject:Message-Id; b=tPI0IR73Fbjdz+I+s/KHobUsOEcTdZRQXNKIj8Lk7sV1ImMKtb9pDCxTzNkBWnJoISDqx1kXmREm52z59ryhpsDspb6VsgrNjKvIUistoNvq1xrtygmKL26wbhB2zWWw6HRU4C1pVrrqmi1l2gRS5L3NbZLmWkjLdK9LeFSWPvw= 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=GGddqO6w; 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="GGddqO6w" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 740631F000E9; Sun, 28 Jun 2026 20:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1782677228; bh=1BrJfb4oyuxdyd7i2S/mJMFRknVNWsjkcNRqDmRNAMM=; h=Date:To:From:Subject; b=GGddqO6wlTliuYOBV2MrqZG3B5gGmE3Qz0uiOSi9qNcZqbFFF+j1P53RhD+UPRY7P iqk4fspn5US3oWaYPK8UcmfARbGekk+bpvTUtWOP5UFqh4Kb+9AYNYs/qRRqztfdKj eOdz2jqEgwJA7rE3E7dEfY3JNgSceMx4cQTaoH8g= Date: Sun, 28 Jun 2026 13:07:08 -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,joshua.hahnjy@gmail.com,david@kernel.org,imran.f.khan@oracle.com,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-vmstat-avoid-taking-zone-lock-in-proc-buddyinfo-reads.patch added to mm-new branch Message-Id: <20260628200708.740631F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/vmstat: avoid taking zone lock in /proc/buddyinfo reads has been added to the -mm mm-new branch. Its filename is mm-vmstat-avoid-taking-zone-lock-in-proc-buddyinfo-reads.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmstat-avoid-taking-zone-lock-in-proc-buddyinfo-reads.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: Imran Khan Subject: mm/vmstat: avoid taking zone lock in /proc/buddyinfo reads Date: Thu, 4 Jun 2026 21:42:45 +0800 frag_show_print() just reads zone->free_area[order].nr_free, so it can safely do this without needing the zone->lock. Pass nolock=true from frag_show(), so that walk_zones_in_node() can skip the zone->lock acquisition. Link: https://lore.kernel.org/20260604134245.1580287-1-imran.f.khan@oracle.com Signed-off-by: Imran Khan Reviewed-by: Joshua Hahn Acked-by: Vlastimil Babka (SUSE) Reviewed-by: Lorenzo Stoakes Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- mm/vmstat.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/vmstat.c~mm-vmstat-avoid-taking-zone-lock-in-proc-buddyinfo-reads +++ a/mm/vmstat.c @@ -1568,7 +1568,7 @@ static void frag_show_print(struct seq_f static int frag_show(struct seq_file *m, void *arg) { pg_data_t *pgdat = (pg_data_t *)arg; - walk_zones_in_node(m, pgdat, true, false, frag_show_print); + walk_zones_in_node(m, pgdat, true, true, frag_show_print); return 0; } _ Patches currently in -mm which might be from imran.f.khan@oracle.com are mm-vmstat-avoid-taking-zone-lock-in-proc-buddyinfo-reads.patch