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 CBFDE40D569 for ; Sun, 28 Jun 2026 02:38:07 +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=1782614289; cv=none; b=cISpTgUp/mcGuRFx8dhOFbODRfWNXpCJ1C41cYLmPv1KaWkC2Fd/sqaHwqJZCVHbTC8xMkcrFlKEriSnc5hrbMjZ+xTmvKIT1wNV9cdOO4e4WpOTARxgIhqiYqsXoESp5KHF9jqUhCC3lzbKCSzsVMpgFRSw2u1Uc2w0pafOfUg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782614289; c=relaxed/simple; bh=NoQssqrKuEZJ6BPWuKy3FnV3XPVbef9fPNINHueFPCk=; h=Date:To:From:Subject:Message-Id; b=HHNPvk5pueJXnob+//MkcYuJ5fH8+tRTqz91gBRriujyysh7d6PMab0w66PD/mVs+DWRlJCWh0L+gNp9JlgJg64tIUEmyxOc7sAV8caJ6V5OwaAQSMD1bjAeNsFErDOH+LT4vh/a+XQvTRujQc+BeynoGAGQfbBhgUANxANSj2A= 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=Uh7fC8s9; 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="Uh7fC8s9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B2041F000E9; Sun, 28 Jun 2026 02:38:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1782614287; bh=DIMoVaTNOMG8HxjLQPqc0JkG4oBQkkMz5HYaHH2lqlo=; h=Date:To:From:Subject; b=Uh7fC8s9ZFwL/LyWFMy7eJGb6sTbxAU1Hm5Tb+sxEnfBOot7SoVspcppJFx4kG5jV RS1zeIx0w3Y2IpDvz5OeDl6Vv5Qv9PDfLtEynRIUAbxT6qnlyzYDD9os2TNVd/+Zty GiZDqMBvemQ4p9nVdlx26ZH+883HALnfqjcRwT+U= Date: Sat, 27 Jun 2026 19:38:06 -0700 To: mm-commits@vger.kernel.org,ye.liu@linux.dev,akpm@linux-foundation.org From: Andrew Morton Subject: + mm-page_owner-use-migrate_reason_none-instead-of-1-for-last_migrate_reason.patch added to mm-new branch Message-Id: <20260628023807.4B2041F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: mm/page_owner: use MIGRATE_REASON_NONE instead of -1 for last_migrate_reason has been added to the -mm mm-new branch. Its filename is mm-page_owner-use-migrate_reason_none-instead-of-1-for-last_migrate_reason.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-page_owner-use-migrate_reason_none-instead-of-1-for-last_migrate_reason.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: Ye Liu Subject: mm/page_owner: use MIGRATE_REASON_NONE instead of -1 for last_migrate_reason Date: Fri, 26 Jun 2026 10:45:41 +0800 The last_migrate_reason field uses -1 as a sentinel value to mean "no migration has happened". Replace the four bare -1 occurrences with a local MIGRATE_REASON_NONE define so the intent is explicit and the magic number is eliminated. No functional change. Link: https://lore.kernel.org/20260626024550.25677-3-ye.liu@linux.dev Signed-off-by: Ye Liu Cc: Brendan Jackman Cc: Johannes Weiner Cc: Michal Hocko Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Signed-off-by: Andrew Morton --- mm/page_owner.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) --- a/mm/page_owner.c~mm-page_owner-use-migrate_reason_none-instead-of-1-for-last_migrate_reason +++ a/mm/page_owner.c @@ -21,6 +21,13 @@ */ #define PAGE_OWNER_STACK_DEPTH (16) +/* + * Used to indicate that a page has never been migrated, as the valid + * migrate_reason values are non-negative enum members (MR_* in + * include/linux/migrate_mode.h). + */ +#define MIGRATE_REASON_NONE (-1) + struct page_owner { unsigned short order; short last_migrate_reason; @@ -339,7 +346,7 @@ noinline void __set_page_owner(struct pa depot_stack_handle_t handle; handle = save_stack(gfp_mask); - __update_page_owner_handle(page, handle, order, gfp_mask, -1, + __update_page_owner_handle(page, handle, order, gfp_mask, MIGRATE_REASON_NONE, ts_nsec, current->pid, current->tgid, current->comm); inc_stack_record_count(handle, gfp_mask, 1 << order); @@ -596,7 +603,7 @@ print_page_owner(char __user *buf, size_ if (ret >= count) goto err; - if (page_owner->last_migrate_reason != -1) { + if (page_owner->last_migrate_reason != MIGRATE_REASON_NONE) { ret += scnprintf(kbuf + ret, count - ret, "Page has been migrated, last migrate reason: %s\n", migrate_reason_names[page_owner->last_migrate_reason]); @@ -667,7 +674,7 @@ void __dump_page_owner(const struct page stack_depot_print(handle); } - if (page_owner->last_migrate_reason != -1) + if (page_owner->last_migrate_reason != MIGRATE_REASON_NONE) pr_alert("page has been migrated, last migrate reason: %s\n", migrate_reason_names[page_owner->last_migrate_reason]); page_ext_put(page_ext); @@ -826,7 +833,7 @@ static void init_pages_in_zone(struct zo /* Found early allocated page */ __update_page_owner_handle(page, early_handle, 0, 0, - -1, local_clock(), current->pid, + MIGRATE_REASON_NONE, local_clock(), current->pid, current->tgid, current->comm); count++; ext_put_continue: _ Patches currently in -mm which might be from ye.liu@linux.dev are mm-page_owner-extract-skip_buddy_pages-helper-to-unify-buddy-page-skipping.patch mm-page_owner-use-migrate_reason_none-instead-of-1-for-last_migrate_reason.patch mm-page_owner-hoist-config_memcg-to-function-level-for-print_page_owner_memcg.patch mm-page_owner-add-missing-newline-to-count_threshold-format-string.patch mm-page_owner-move-free_ts_nsec-output-to-free-section-in-__dump_page_owner.patch mm-page_owner-drop-redundant-page_owner-prefix-from-static-symbols.patch mm-page_owner-clamp-skip_buddy_pages-pfn-advance-at-max_order_nr_pages-boundary.patch mm-page_owner-use-memcg_data-snapshot-instead-of-pagememcgkmem-to-avoid-toctou-vm_bug_on.patch