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 E550B317173; Fri, 3 Jul 2026 12:47:48 +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=1783082870; cv=none; b=uOf1b6a8v+KImGwZRGfgF7Cc8XyWyTFQN0Wd84QJQ6k/r7X4J61dl62pJ0abk0bLUbYrp1UA4F1uIts/G8KnbElZd0lcP3WUw8y2hvOG5mTGrsb8cFo9WQ1/eVtfeWOHmXx3LmiBvogI1NidPY/pKhMOdDCV/T8BPR7U2xCZWDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783082870; c=relaxed/simple; bh=7iW+dYPTqpIT4kxV9kA9m2LZjmErTJWWocSxRdzPfng=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tfp1x4rO2M48XkmpztqlJKyE+6QqfXP+nQ0VFRXSvuAkKgBejjmnGB9bjaKGT92ZYL4ECcAQnWma7diaZhIYRNmFuhaLiIY2+G3+Je9sCd2kZbCCYc5PCGtMm21cbcyO5wQ8eOWcNtkOzf9O2aNrw7DRt4iA9LohFBu6GeHnyHw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=apno0fpW; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="apno0fpW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 842E11F000E9; Fri, 3 Jul 2026 12:47:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783082868; bh=NPYOzd2RjFg1ddO/ZLQh27mhHcI8iJ031pBNVEV3ouY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=apno0fpWqD4HAfuc6YJmV2FSvla0WDZdWmjkMYLOExNvhMWLblylwUrBaWPl+Y5Lr vVPu9XkgOxIw0MTVsuw5+DVKZC0dSrPeeC6RuiA5dpyzCCwzsXjBCt7dvQPaP3upDF UoOQS7pIlBb/lzqdAGul1gwrToCtjFKmgxBz7SIClX0i1cAc11z7E0BdTwYPnCBl/L WsqiCuPbM+rXit3Wd9ri2eZps2cuhVzIcraC6ZmeRWB0YpVEo7r6NnXTZwc3P9bw5h w/SXZ2mFLUM0B6FeZybDNRlTX75MnL6BGPc28ROvk0jrqPfpOVBW6CHnxz4ZNq+eRI djOJZ+YWKunJA== Message-ID: <997c1a4d-ee99-4214-be58-7ceb3b9b9a36@kernel.org> Date: Fri, 3 Jul 2026 14:47:32 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 00/18] mm: Some cleanups for page allocator APIs Content-Language: en-US To: Brendan Jackman , Andrew Morton , Suren Baghdasaryan , Michal Hocko , Johannes Weiner , Zi Yan , Muchun Song , Oscar Salvador , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Ying Huang , Alistair Popple , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt Cc: "Harry Yoo (Oracle)" , Gregory Price , Alexei Starovoitov , Matthew Wilcox , Hao Ge , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, derkling@google.com, reijiw@google.com, Yosry Ahmed , JP Kobryn , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Sean Christopherson , Paolo Bonzini , kvm@vger.kernel.org, Thomas Gleixner , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Robin Holt , Steve Wahl , Arnd Bergmann , Greg Kroah-Hartman , Dimitris Michailidis , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni References: <20260703-alloc-trylock-v5-0-c87b714e19d3@google.com> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; keydata= xsFNBFZdmxYBEADsw/SiUSjB0dM+vSh95UkgcHjzEVBlby/Fg+g42O7LAEkCYXi/vvq31JTB KxRWDHX0R2tgpFDXHnzZcQywawu8eSq0LxzxFNYMvtB7sV1pxYwej2qx9B75qW2plBs+7+YB 87tMFA+u+L4Z5xAzIimfLD5EKC56kJ1CsXlM8S/LHcmdD9Ctkn3trYDNnat0eoAcfPIP2OZ+ 9oe9IF/R28zmh0ifLXyJQQz5ofdj4bPf8ecEW0rhcqHfTD8k4yK0xxt3xW+6Exqp9n9bydiy tcSAw/TahjW6yrA+6JhSBv1v2tIm+itQc073zjSX8OFL51qQVzRFr7H2UQG33lw2QrvHRXqD Ot7ViKam7v0Ho9wEWiQOOZlHItOOXFphWb2yq3nzrKe45oWoSgkxKb97MVsQ+q2SYjJRBBH4 8qKhphADYxkIP6yut/eaj9ImvRUZZRi0DTc8xfnvHGTjKbJzC2xpFcY0DQbZzuwsIZ8OPJCc LM4S7mT25NE5kUTG/TKQCk922vRdGVMoLA7dIQrgXnRXtyT61sg8PG4wcfOnuWf8577aXP1x 6mzw3/jh3F+oSBHb/GcLC7mvWreJifUL2gEdssGfXhGWBo6zLS3qhgtwjay0Jl+kza1lo+Cv BB2T79D4WGdDuVa4eOrQ02TxqGN7G0Biz5ZLRSFzQSQwLn8fbwARAQABzSNWbGFzdGltaWwg QmFia2EgPHZiYWJrYUBrZXJuZWwub3JnPsLBsAQTAQoAWhYhBKlA1DSZLC6OmRA9UCJPp+fM gqZkBQJqFFy6GxSAAAAAAAQADm1hbnUyLDIuNSsxLjEyLDIsMgIbAwUJGtCBUAULCQgHAwUV CgkICwUWAgMBAAIeBQIXgAAKCRAiT6fnzIKmZJIUEADFx/tREzUImHrEwVHeSvDFmA7tJysI UVrlvrM09E7GIuzphzv7jYmo8n3ANpCczLEVr4G0syYQdTigaZgv3+FQDIIzhKih1IHhu1Ei XHlywNWKnQxxQEUNi5Mwx43wQz5XVw9F1A7gtKBKNtfogO511hAbrzagrYajyQacEJ/+sfhZ 9Da8ltHIXD8pcYaHUfQgEusCgmEd9+KrUwrTbckFKmYq5chuE6yJ4J0EmWknL096jIE6CnzF FRslQ3B1UKDjxVsm1ZHfir5NeWszLkTvGFsddFaWTgh8UycESG6VQzKXjjewXu2pG7YQYRpj QKm1W5X2TkwWkXRBZTmfmbhxIUMh3+zf5wQ463rSmDN/8v81tdqBtAW6rH/kzg1GvkaTHXn0 507yEHFzBksk2viAuIxxr7km8+/KARYLIdGtx30EG8cKzAUZOK6WqxtNCsXUJNrVE8CWrCaD icoNu7Fs1c5hmPHdSTnU48ce67449DdnO4neLSNhRiGlMHJgfJUmgrxu/hcYeOZ3haWmEQ2w uW1Mh01OHi8QZHCEyAbABrPs9GUgccc/4eYXX9hIgxfSkYzn8f+8NuIFPWl/0uTvjgqU29FQ SbzOLxHq9439Ox40G5mS5eZXRGxITYR+6TXvRGI6P/264jvflnr/pDGUttaikU+0W+1uxgKH cmYbEc7ATQRbGTU1AQgAn0H6UrFiWcovkh6EXVcl+SeqyO6JHOPm+e9Wu0Vw+VIUvXZVUVVQ La1PQDUi6j00ChlcR66g9/V0sPIcSutacPKfdKYOBvzd4rlhL8rfrdEsQw5ApZxrA8kYZVMh FmBRKAa6wos25moTlMKpCWzTH84+WO5+ziCTsTUZASAToz3RdunTD+vQcHj0GqNTPAHK63sf bAB2I0BslZkXkY1RLb/YhuA6E7JyEd2pilZOrIuBGl/5q2qSakgnAVFWFBR/DO27JuAksYnq +aH8vI0xGvwn75KqSk4UzAkDzWSmO4ZHuahKtQgZNsMYV+PGayRBX9b9zbldzopoLBdqHc4n jQARAQABwsF8BBgBCgAmAhsMFiEEqUDUNJksLo6ZED1QIk+n58yCpmQFAmfIHFQFCRYU6J8A CgkQIk+n58yCpmS2PA//bqN1LfcotmArgElsa+0EGZSQlYgK48pm8WAeTXTngudP9IJ4SuKY HR5RNjHcBeqN+Me0zxRqYzRb8nGanHEkDyf4Im8DQM8d6vbyU+FcPmG4skud4kgS1zMHnlVd SXfSIwKC/hKgdHG8aBV7545Lz9X6Iohea+94wneD0aw/hqF+QWewGZhWJriWAZtvEkzNjQOi 4U9F/trLten/x7bpphDSnDMKJtITbtzATT1Dq7o7VpIUK1nCTQALMuMjKCdi8OdU/+V+R3O4 0PXWvX8qrvqYapVbZ+9KqT74FsuB0Ya9uXwgBF2Q6cRuETZk5vqaqKxzqoQZCO8AOz/58j6O 2RHNy/mZEN+7tJ5Tsq42zVJ4jxsT8b9YplavCMsnBgDeRWhcbYhCyttoL7nYISyWg4kQYZ/P wIV3OuNv2f8iKYsxNsRuClOAF82+gvqOy1/1pprFjy8uo2pkoOrb63aOP3vO5VHnRKgra6dq NcaZ+c6J4H+nEJGi2SkHAUJz5oBzuThvPudLvPA/SK8sKoM01IRxSihev/S/5WLazXB1PGem OCbvzC1IjWJJraxiDJ5IygokapUa2RP7+WBR22skQ3SSl6G107QgWKSyTOGWEaRmV53vxQLV jXuCmzSSasTL60zq5yGrT4/DYQVSNEUiUbG4pYekxJujNeEDkUlky0Y= In-Reply-To: <20260703-alloc-trylock-v5-0-c87b714e19d3@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/3/26 14:31, Brendan Jackman wrote: > Based on mm-new. Seems ready for mm-new to me. I suspect most further non-trivial page allocator work will conflict, so better have it in mm to be based upon. I was worried about Johannes' defrag fixes [1] that were supposed to be stable bacported and thus would be better to add (the next revision) to mm-new first. But seems like if I apply this series on mm-new, and then [1] on top, nothing conflicts, so the ordering shouldn't matter. [1] https://lore.kernel.org/all/20260626182215.1107966-1-hannes@cmpxchg.org/ > This depends on moving alloc_tag to mm/: > https://lore.kernel.org/all/aj5QBtJcphPElczI@lucifer/ > > Some tweaks and cleanups for page allocator entrypoint and flags. This > is motivated by preparation for __GFP_UNMAPPED [1] (which will probably > become ALLOC_UNMAPPED in its next iteration), but all this is supposed > to be an improvement to the codebase in its own right: unifying code > paths, reducing API surface, and removing GFP flags. > > [1] https://lore.kernel.org/all/20260320-page_alloc-unmapped-v2-0-28bf1bd54f41@google.com/ > > This started with unifying __alloc_frozen_pages[_nolock]_noprof() and > expanded from there. > > Unifying the nolock allocator entrypoint with the normal allocator > entrypoint means adding an alloc_flags argument to the later (only > exposed within mm/). This presents an opportunity to take advantage of > that arg to remove some GFP flags, if we add that alloc_flags arg a bit > more broadly to allocator entrypoints. > > To distinguish between mm-internal and "public" allocator entrypoints, > it makes sense to use the __ prefix. There are already some public APIs > with that prefix. For *alloc_pages*, just removing those variants seems > like a nice cleanup anyway, so do that. For get_free_pages, the "__" > variant is the _only_ variant and it's very widely used, so it doesn't > seem worthwhile to modify that. Therefore, scope this "__" change > specifically to the *alloc_pages* API, which means we leave the > *folio_alloc* API untouched too, even though that could probably be > cleaned up if so desired. > > Tested: > > - KVM, mm, and BPF selftests in a QEMU VM > > - kunit.py on x86_64 > > - For the ALLOC_NO_CODETAG bits I just booted a VM and read > /proc/allocinfo. I confirmed that if I remove ALLOC_NO_CODETAG, the > kernel crashes in early boot, so I was at least booting code that > depends on this logic. > > I used Google's internal version of Antigravity (AI coding harness) to > do the repetitive bits, those commits are marked with Assisted-by, the > rest is manual. > > Signed-off-by: Brendan Jackman > --- > Changes in v5: > - Just trivial non-functional fixes. > - Link to v4: https://patch.msgid.link/20260702-alloc-trylock-v4-0-0af8ff387e80@google.com > > Changes in v4: > - Fixed some (harmless) missing applications of ac->alloc_flags (local > Sashiko) > - Fixed various build issues. > - Note that Sashiko pointed out a KMSAN build issue [0], I have > fixed it but KMSAN builds are currently broken by objtool [1]. At least > mm/kmsan/init.c compiles. > [2] https://lore.kernel.org/all/20260629141642.628271F00A3D@smtp.kernel.org/ > [3] https://lore.kernel.org/all/20260630104434.GC751831@noisy.programming.kicks-ass.net/t/#u > - Avoided setting ALLOC_NOFRAGMENT under ALLOC_NOLOCK (Sashiko, Harry) > - Added patch to tweak alloc_flags_cma() interface (Vlastimil) > - More commit messages fixups (various) > - Added patch to create can_spin_trylock() (Harry) > - Link to v3: https://patch.msgid.link/20260629-alloc-trylock-v3-0-57bef0eadbc2@google.com > > Changes in v3: > - Created mm/page_alloc.h > - Fixed EXPORT_SYMBOL() issues > - Reworded commit messages per Sashiko's pointers > - Dropped rename of alloc_flags arg in prepare_alloc_pages() (Suren) > - Renamed gfp_to_alloc_flags_nonblocking() too after rebasing onto: > https://lore.kernel.org/all/20260623004600.113347-1-jp.kobryn@linux.dev/ > - Link to v2: https://patch.msgid.link/20260622-alloc-trylock-v2-0-31f31367d420@google.com > > Changes in v2: > - Fixed up whitespace in nolock unification patch > - Introduced ALLOC_DEFAULT to replace literal 0 for alloc_flags > - All other patches are new > - Link to v1: https://patch.msgid.link/20260617-alloc-trylock-v1-1-83fd7858832e@google.com > > --- > Brendan Jackman (17): > mm/page_alloc: rename ALLOC_TRYLOCK -> ALLOC_NOLOCK > mm/page_alloc: some renames to clarify alloc_flags scopes > mm: name some args in a function declaration > mm: Split out internal page_alloc.h > mm/page_alloc: unify __alloc_frozen_pages[_nolock]_noprof() > mm/page_alloc: relax GFP WARN in nolock allocs > mm: move some stuff to mm/page_alloc.h > perf/x86/intel: Use higher-level allocator API > KVM: VMX: Use higher-level allocator API > x86/virt: Use higher-level allocator API > sgi-xp: Use higher-level allocator API > net/funeth: Switch to higher-level allocator API > mm: Remove __alloc_pages_node() > mm: Move __alloc_pages() to mm/page_alloc.h > mm: replace __GFP_NO_CODETAG with ALLOC_NO_CODETAG > mm/page_alloc: drop alloc_flags arg from alloc_flags_cma() > mm: factor out can_spin_trylock() > > Vlastimil Babka (SUSE) (1): > mm: remove the __GFP_NO_OBJ_EXT flag > > Documentation/admin-guide/cgroup-v1/cpusets.rst | 2 +- > Documentation/admin-guide/mm/transhuge.rst | 2 +- > MAINTAINERS | 1 + > arch/x86/events/intel/ds.c | 6 +- > arch/x86/kvm/vmx/vmx.c | 2 +- > arch/x86/virt/hw.c | 2 +- > drivers/misc/sgi-xp/xpc_uv.c | 5 +- > drivers/net/ethernet/fungible/funeth/funeth_rx.c | 2 +- > include/linux/alloc_tag.h | 4 +- > include/linux/gfp.h | 54 +--- > include/linux/gfp_types.h | 7 - > include/linux/skbuff.h | 2 +- > include/trace/events/mmflags.h | 10 +- > mm/alloc_tag.c | 23 +- > mm/compaction.c | 5 +- > mm/hugetlb.c | 4 +- > mm/internal.h | 275 ++------------------ > mm/khugepaged.c | 1 + > mm/kmsan/init.c | 2 +- > mm/memory-failure.c | 1 + > mm/memory_hotplug.c | 1 + > mm/mempolicy.c | 11 +- > mm/migrate.c | 1 + > mm/mm_init.c | 1 + > mm/page_alloc.c | 269 ++++++++++--------- > mm/page_alloc.h | 312 +++++++++++++++++++++++ > mm/page_frag_cache.c | 6 +- > mm/page_isolation.c | 1 + > mm/page_owner.c | 2 +- > mm/page_reporting.c | 1 + > mm/show_mem.c | 1 + > mm/shuffle.c | 1 + > mm/slub.c | 17 +- > mm/swap.c | 1 + > mm/vmscan.c | 1 + > mm/vmstat.c | 1 + > tools/include/linux/gfp_types.h | 7 - > 37 files changed, 536 insertions(+), 508 deletions(-) > --- > base-commit: 32af3ff0925368eff29b2fed62f154150eb5dc10 > change-id: 20260617-alloc-trylock-14ad37dab337 > > Best regards, > -- > Brendan Jackman >