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 85C13233942 for ; Tue, 25 Aug 2026 01:54:05 +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=1787622850; cv=none; b=re9BpGYZDNmdXD+MvEjG+GX0Y2+LPgKeZQRbOQ6IQq53vFI2SZ6sNAVyeQi/s+3su5ALHqR82hIIY5eRKBrbRHfBdinK/sWYPWjvNnqZsLXKpgXiIJfiXnvaspigOgl3p5rpCQRA0XdVGGpY9CPGBYF9sd79CzL2HNY08SuxfuI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787622850; c=relaxed/simple; bh=7EP+hDzq00K6jvPaCWf2krpKmwXIJnaVlrzzXiHdG/I=; h=Date:To:From:Subject:Message-Id; b=OEC2FR2qzvyz0oujHhw+EnucgECFjJ96krlxMMj7FbWMHAJRaz/sQZOEG2KNsU5KoZe/X0HQyATejPs1m/FUIkGmbO0YlYGLfkQFTIUfdbNNA27J3YLTMx5dB/0LlEaQBWm0yBBJKjUhTwGtz+feDBdDKq8BZv621WoPy8RQQIg= 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=VZgj4Bri; 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="VZgj4Bri" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 025501F00A3A; Tue, 25 Aug 2026 01:54:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1787622845; bh=oZ8jZjvFMVsfURmKvobWZYBxhWvwMWBG+NNFKjDfXvQ=; h=Date:To:From:Subject; b=VZgj4BriMTg1We8lC6CmW0mx7fcTZrqMQB+c3hPCyLUcJipe3aIRZLJ0qV8BG8Cuu HSogM7H1syihHIERrvRQogHgME7kKzQAPm7n/b2XhAb9JUXXOVRr/8Fi4JyLx17xAs jGhkeukpbQgfijJe30l0APfALT2Wy9Mvl75ju0Ps= Date: Mon, 24 Aug 2026 18:54:04 -0700 To: mm-commits@vger.kernel.org,surenb@google.com,hao.ge@linux.dev,abhishekbapat@google.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] alloc_tag-expose-boot-time-compression-configuration.patch removed from -mm tree Message-Id: <20260825015405.025501F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: alloc_tag: expose boot-time compression configuration has been removed from the -mm tree. Its filename was alloc_tag-expose-boot-time-compression-configuration.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Abhishek Bapat Subject: alloc_tag: expose boot-time compression configuration Date: Wed, 5 Aug 2026 17:29:52 +0000 Currently, userspace has limited visibility into the exact active runtime state of memory allocation profiling and its page extension compression ('sysctl.vm.mem_profiling={0|1|never}[,compressed]'). While reading the sysctl provides basic on/off status, it is currently impossible for userspace to natively determine whether page-tag compression was successfully enabled without scraping dmesg boot logs. Add a new read-only sysctl representing how compression was configured at boot time. Link: https://lore.kernel.org/c795f8089f82841e8a6e00d7ca286da2b23aeb7b.1785950530.git.abhishekbapat@google.com Signed-off-by: Abhishek Bapat Acked-by: Suren Baghdasaryan Cc: Hao Ge Signed-off-by: Andrew Morton --- Documentation/mm/allocation-profiling.rst | 11 +++++++++++ mm/alloc_tag.c | 6 ++++++ 2 files changed, 17 insertions(+) --- a/Documentation/mm/allocation-profiling.rst~alloc_tag-expose-boot-time-compression-configuration +++ a/Documentation/mm/allocation-profiling.rst @@ -43,6 +43,17 @@ sysctl: warnings produced by allocations made while profiling is disabled and freed when it's enabled. + /proc/sys/vm/mem_profiling_compressed + + 1: Page alloc tag compression is enabled. + + 0: Page alloc tag compression is disabled. + + This reflects a static boot-time configuration of how page allocation tags are + stored (in page flags when compression is enabled and in page_ext when disabled). + Toggling ``mem_profiling`` at runtime does not change the state of + ``mem_profiling_compressed``. + Runtime info: /proc/allocinfo --- a/mm/alloc_tag.c~alloc_tag-expose-boot-time-compression-configuration +++ a/mm/alloc_tag.c @@ -961,6 +961,12 @@ static const struct ctl_table memory_all .mode = 0644, .proc_handler = proc_mem_profiling_handler, }, + { + .procname = "mem_profiling_compressed", + .data = &mem_profiling_compressed, + .mode = 0444, + .proc_handler = proc_do_static_key, + }, }; static void __init sysctl_init(void) _ Patches currently in -mm which might be from abhishekbapat@google.com are