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 3B4D713B294 for ; Thu, 15 Feb 2024 23:34:16 +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=1708040056; cv=none; b=EW/5/9jhaWLIYoSB8moQ/JF1B8vfLVapZyPCHHEevilumiXvJwQXa2gGTt9gy7m8U/N9nHdL6JXbGxlmAoSGycb5rCINeZN7Os+DkDTbvIMhSo/CjFhUDTOXPQ0sp3x3H3rp5s6F5jTygwM6b+sDVzHsG9A9WLU1b6wh9JsW0xY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708040056; c=relaxed/simple; bh=ED7GSmnvOPOukA1BD5HJrjWpi0HForQ5VCvCUSCn/pY=; h=Date:To:From:Subject:Message-Id; b=jb4Tu6F+4/+uvm3h1yXc50VmNw+uOvJqZoegjdq6JQ0/7Qe17kwxi0U4ga9tt/kHKiXxOGYInBpfkIAx05f8AuYZ2DHKU3162GmBYcE2v5tlJxfPjVBQOW4kaCEiJ5SwAe9l2m4yKaVYAryqFEBlOcGFa7nGVUmxj59Nz2Fa5h8= 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=k1x9afQz; 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="k1x9afQz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00CECC433F1; Thu, 15 Feb 2024 23:34:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1708040056; bh=ED7GSmnvOPOukA1BD5HJrjWpi0HForQ5VCvCUSCn/pY=; h=Date:To:From:Subject:From; b=k1x9afQzmSbznMpR6YCN3T0ZWQpwgmSye126sRiIPR9K/q0oHxeqPy5s0s5Gz5THY Ed69bRepFxUgXEu0SgjKViSuI7TzO2bWzGLT+GyrODauiMXMI4rfduKLriWU5MXEYV dGE6PdJJACqUB+DZxOTb2zCc08RlKTvGmfGuGKSU= Date: Thu, 15 Feb 2024 15:34:15 -0800 To: mm-commits@vger.kernel.org,vbabka@suse.cz,mhocko@suse.com,glider@google.com,elver@google.com,andreyknvl@gmail.com,osalvador@suse.de,akpm@linux-foundation.org From: Andrew Morton Subject: + mmpage_owner-update-documentation-regarding-page_owner_stacks.patch added to mm-unstable branch Message-Id: <20240215233416.00CECC433F1@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: update Documentation regarding page_owner_stacks has been added to the -mm mm-unstable branch. Its filename is mmpage_owner-update-documentation-regarding-page_owner_stacks.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mmpage_owner-update-documentation-regarding-page_owner_stacks.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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: Oscar Salvador Subject: mm,page_owner: update Documentation regarding page_owner_stacks Date: Thu, 15 Feb 2024 22:59:07 +0100 Update page_owner documentation including the new page_owner_stacks feature to show how it can be used. Link: https://lkml.kernel.org/r/20240215215907.20121-8-osalvador@suse.de Signed-off-by: Oscar Salvador Reviewed-by: Vlastimil Babka Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Michal Hocko Signed-off-by: Andrew Morton --- Documentation/mm/page_owner.rst | 45 ++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) --- a/Documentation/mm/page_owner.rst~mmpage_owner-update-documentation-regarding-page_owner_stacks +++ a/Documentation/mm/page_owner.rst @@ -24,6 +24,11 @@ fragmentation statistics can be obtained each page. It is already implemented and activated if page owner is enabled. Other usages are more than welcome. +It can also be used to show all the stacks and their outstanding +allocations, which gives us a quick overview of where the memory is going +without the need to screen through all the pages and match the allocation +and free operation. + page owner is disabled by default. So, if you'd like to use it, you need to add "page_owner=on" to your boot cmdline. If the kernel is built with page owner and page owner is disabled in runtime due to not enabling @@ -68,6 +73,46 @@ Usage 4) Analyze information from page owner:: + cat /sys/kernel/debug/page_owner_stacks/show_stacks > stacks.txt + cat stacks.txt + prep_new_page+0xa9/0x120 + get_page_from_freelist+0x7e6/0x2140 + __alloc_pages+0x18a/0x370 + new_slab+0xc8/0x580 + ___slab_alloc+0x1f2/0xaf0 + __slab_alloc.isra.86+0x22/0x40 + kmem_cache_alloc+0x31b/0x350 + __khugepaged_enter+0x39/0x100 + dup_mmap+0x1c7/0x5ce + copy_process+0x1afe/0x1c90 + kernel_clone+0x9a/0x3c0 + __do_sys_clone+0x66/0x90 + do_syscall_64+0x7f/0x160 + entry_SYSCALL_64_after_hwframe+0x6c/0x74 + stack_count: 234 + ... + ... + echo 7000 > /sys/kernel/debug/page_owner_stacks/count_threshold + cat /sys/kernel/debug/page_owner_stacks/show_stacks> stacks_7000.txt + cat stacks_7000.txt + prep_new_page+0xa9/0x120 + get_page_from_freelist+0x7e6/0x2140 + __alloc_pages+0x18a/0x370 + alloc_pages_mpol+0xdf/0x1e0 + folio_alloc+0x14/0x50 + filemap_alloc_folio+0xb0/0x100 + page_cache_ra_unbounded+0x97/0x180 + filemap_fault+0x4b4/0x1200 + __do_fault+0x2d/0x110 + do_pte_missing+0x4b0/0xa30 + __handle_mm_fault+0x7fa/0xb70 + handle_mm_fault+0x125/0x300 + do_user_addr_fault+0x3c9/0x840 + exc_page_fault+0x68/0x150 + asm_exc_page_fault+0x22/0x30 + stack_count: 8248 + ... + cat /sys/kernel/debug/page_owner > page_owner_full.txt ./page_owner_sort page_owner_full.txt sorted_page_owner.txt _ Patches currently in -mm which might be from osalvador@suse.de are lib-stackdepot-fix-first-entry-having-a-0-handle.patch lib-stackdepot-move-stack_record-struct-definition-into-the-header.patch mmpage_owner-maintain-own-list-of-stack_records-structs.patch mmpage_owner-implement-the-tracking-of-the-stacks-count.patch mmpage_owner-display-all-stacks-and-their-count.patch mmpage_owner-filter-out-stacks-by-a-threshold.patch mmpage_owner-update-documentation-regarding-page_owner_stacks.patch