From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-189.mta1.migadu.com (out-189.mta1.migadu.com [95.215.58.189]) (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 964DB363082 for ; Wed, 1 Jul 2026 05:45:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.189 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782884722; cv=none; b=CyG0vA6v3ObtSjRfdxXj8rnC83Bcs93WC0NxCFK8U4pSYRYjfCVUvZ1VYodISvg8oY1euBRFp47TeJBl0TZqqVWsqQ0wpObeZKRT8kLUTQDT94fXTwWpzHOY+R3KYxdk8DP1LBYHXg0MLIMYjt8+0+3j2uq0rpdTeVMurxsL4oU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782884722; c=relaxed/simple; bh=0ROAb9jVZySsEF0HotgYTIXFVkrsJ63g7ogT97W0AVQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OgEGCedxgpWTKtZUVB6w4Uf/pTB+k1hXpZe00ZqVQUJivW7va3ZNXST0SjgphLCuS0/nS3gQvKhMnKZQ9gi/lRWX5y8I1NNivNf40Nz25gHch25hGgwxGXcv70Z9r0VdjCwHLsnHFZzUpr2qjvBP0+lZZDOjnbuaEOrD2uIbcps= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=A3L+Kccs; arc=none smtp.client-ip=95.215.58.189 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="A3L+Kccs" Message-ID: <8dce5685-c215-4876-93d9-3cec4dcb6173@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1782884717; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/eBy/cy5VU0ZqBJNyM4Ph2gzU/Wof+YpQ8uN8ahCb/c=; b=A3L+Kccsn/MNQIVglrZ4DBTnF5bN7TbI1Qf70InFJpoNesB515JIh1V2POmopZFmMmCQAe DgqN9Fmxc+maXIPRp3Pt0LSuTF3HvjOoIiQJ+01y7EY7wCP07R/yzQZRjDXRVW6dalFHZ2 t79Txc3e/J7kMlnOHdFPXePV/U9nL/s= Date: Wed, 1 Jul 2026 13:45:00 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v4 0/7] mm/page_owner: misc cleanups To: Andrew Morton Cc: Zi Yan , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260701012239.315262-1-ye.liu@linux.dev> <20260630204130.175e9a2addae86058327918e@linux-foundation.org> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Ye Liu In-Reply-To: <20260630204130.175e9a2addae86058327918e@linux-foundation.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2026/7/1 11:41, Andrew Morton 写道: > On Wed, 1 Jul 2026 09:22:26 +0800 Ye Liu wrote: > >> v4: >> - Patch 2: also update scripts/gdb/linux/page_owner.py to use MR_NEVER >> instead of the hardcoded -1. >> - https://lore.kernel.org/all/20260630015331.147174-1-ye.liu@linux.dev/ > > I'm seeing more changes than described here? > > > Thanks, I updated mm.git to this version. > > Here's how v4 altered mm.git: > Patch[1] depends on this patch series and should be placed together with this part. I will send V5 including both patches. [1]:https://lore.kernel.org/all/20260625014708.87386-1-ye.liu@linux.dev/ > > mm/page_owner.c | 16 +++------------- > scripts/gdb/linux/page_owner.py | 4 +++- > 2 files changed, 6 insertions(+), 14 deletions(-) > > --- a/mm/page_owner.c~b > +++ a/mm/page_owner.c > @@ -428,12 +428,6 @@ void __folio_copy_owner(struct folio *ne > * to skip less than the full buddy block, but that is acceptable for page owner > * iteration purposes. > * > - * The lockless read of buddy_order_unsafe() can also return a garbage order if > - * the page is concurrently allocated and PageBuddy is cleared between the check > - * and the read. Clamp the advance at the next MAX_ORDER_NR_PAGES boundary so > - * that a bogus order cannot carry @pfn into an unvalidated memory section, > - * which would break callers that rely on boundary-aligned pfn_valid() checks. > - * > * Return: true if the page was skipped (caller should continue its loop), > * false if the page is not a buddy page and should be processed normally. > */ > @@ -445,12 +439,8 @@ static inline bool skip_buddy_pages(unsi > return false; > > order = buddy_order_unsafe(page); > - if (order <= MAX_PAGE_ORDER) { > - unsigned long new_pfn = *pfn + (1UL << order); > - unsigned long boundary = ALIGN(*pfn + 1, MAX_ORDER_NR_PAGES); > - > - *pfn = min(new_pfn, boundary) - 1; > - } > + if (order <= MAX_PAGE_ORDER) > + *pfn += (1UL << order) - 1; > > return true; > } > @@ -561,7 +551,7 @@ static inline int print_page_owner_memcg > cgroup_name(memcg->css.cgroup, name, sizeof(name)); > ret += scnprintf(kbuf + ret, count - ret, > "Charged %sto %smemcg %s\n", > - (memcg_data & MEMCG_DATA_KMEM) ? "(via objcg) " : "", > + PageMemcgKmem(page) ? "(via objcg) " : "", > online ? "" : "offline ", > name); > out_unlock: > --- a/scripts/gdb/linux/page_owner.py~b > +++ a/scripts/gdb/linux/page_owner.py > @@ -34,6 +34,7 @@ class DumpPageOwner(gdb.Command): > max_pfn = None > p_ops = None > migrate_reason_names = None > + mr_never = None > > def __init__(self): > super(DumpPageOwner, self).__init__("lx-dump-page-owner", gdb.COMMAND_SUPPORT) > @@ -65,6 +66,7 @@ class DumpPageOwner(gdb.Command): > self.max_pfn = int(gdb.parse_and_eval("max_pfn")) > self.page_ext_size = int(gdb.parse_and_eval("page_ext_size")) > self.migrate_reason_names = gdb.parse_and_eval('migrate_reason_names') > + self.mr_never = int(gdb.parse_and_eval('MR_NEVER')) > > def page_ext_invalid(self, page_ext): > if page_ext == gdb.Value(0): > @@ -138,7 +140,7 @@ class DumpPageOwner(gdb.Command): > else: > gdb.write('page last free stack trace:\n') > stackdepot.stack_depot_print(page_owner["free_handle"]) > - if page_owner['last_migrate_reason'] != -1: > + if page_owner['last_migrate_reason'] != self.mr_never: > gdb.write('page has been migrated, last migrate reason: %s\n' % self.migrate_reason_names[page_owner['last_migrate_reason']]) > > def read_page_owner(self): > _ > -- Thanks, Ye Liu