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 127BE3F12D0; Thu, 30 Jul 2026 09:01:20 +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=1785402082; cv=none; b=DJzqjkRWB9jg9aZJMKG9JVLe8dW94GMSfmGVL7FSvRtV/LonazIRX9EW+x49KWToqz+oWqLw9t8slh8hDMmBRTn7LPPbkPRvUtKa/smAujM+P622lQKIzkTnUPcvrfRQWVlY+f0Gw7bc+GGsYAUqoInefuw0C2q2JCMw3LEr1WY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785402082; c=relaxed/simple; bh=EgrgXehS8Eem5zAeSBXtfk3b1tTF3b01oPe3aMZL8Lk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PjNLpL0HAFyK9V0byRHNsNOVonvg354qCQGEpMjuMwDVRuYjTKeKeabau09hfqqO9ywvkqmKaR8hMskIPjk6iiy/nbmCIZ+5u8gsQvSy8KDzejm3BqPlSM03VYXtyTPtbZAwQ1noebfDrbS5DdCHR75XkHWs8R46RrbUdjU+IUQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cMAAyTQe; 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="cMAAyTQe" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C16F51F00A3A; Thu, 30 Jul 2026 09:01:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785402080; bh=CepvrJSCofuW+Rbn27Rzxe0iX7nFeJvfMACrLN8SBXg=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=cMAAyTQeOGqrx75vLFrjVKl+Q6ZyYvMe3VzKiXO3gT454huGwem31nWyXRv/q9dlS E3hQqIi3kmO60/5toa+zlCHUuM+g8Wqeu3nhCRRJ+Sf0qZx2N3FkcFXK6YLhYRpLQr t/KYFLKt7fKulDxc4uMA3avGCvf+riDMcZSldx4g+Drk+cDrNxW3LqOsYnI8qChyzL 7VHsgrGNTwXbiZ3BhGlFN+vSFe+V/f8AsAU+/6IPpBHgp5VswFdaspZ9ChgObfb20X +Kdl7lpr/DuwRf+dyPvrYDM1Pns9x4LuCF0BroserOpfZgvlmji+6LlA5kagPgRpPY 2550ObpT+Lr8A== Message-ID: <47b147f2-8c10-4ae4-8023-94839f1110a8@kernel.org> Date: Thu, 30 Jul 2026 11:01:12 +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 0/8] mm/slab: introduce kfree_rcu_nolock() and improve slub_kunit coverage To: Harry Yoo , Andrew Morton , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Alexei Starovoitov , Andrii Nakryiko , Puranjay Mohan , Amery Hung , Sebastian Andrzej Siewior , Clark Williams , Steven Rostedt , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Pedro Falcato , Suren Baghdasaryan , Shengming Hu Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, rcu@vger.kernel.org, bpf@vger.kernel.org References: <20260729-kfree_rcu_nolock-v5-0-a28cdcda9673@kernel.org> <5342124c-4847-4e93-92a4-f3512928c4d1@kernel.org> From: "Vlastimil Babka (SUSE)" Content-Language: en-US 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/30/26 05:08, Harry Yoo wrote: > > > On 7/29/26 11:14 PM, Vlastimil Babka (SUSE) wrote: >> On 7/29/26 10:20, Harry Yoo (Oracle) wrote: >> >> ... >> >>> 8: 8e69c83a1e52 ! 8: aeaf2ab60046 slub_kunit: extend the test for kfree_rcu_nolock() >>> @@ lib/tests/slub_kunit.c: struct test_nolock_context { >>> - gfp_t gfp = (i % 2) ? GFP_KERNEL : GFP_KERNEL_ACCOUNT; >>> + gfp_t gfp = (i & 1) ? GFP_KERNEL : GFP_KERNEL_ACCOUNT; >>> >>> - objects[j] = kmalloc_obj(*objects[j], gfp); >>> +- objects[j] = kmalloc(64, gfp); >>> ++ objects[j] = kmalloc_obj(*objects[j], gfp); >>> if (!objects[j]) { >>> + j--; >>> + while (j >= 0) >>> @@ lib/tests/slub_kunit.c: static void test_kmalloc_kfree(void) >>> } >>> } >>> >>> Link: https://lore.kernel.org/linux-mm/20260427-nolock-api-fix-v2-0-a6b83a92d9a4@kernel.org [1] >>> Link: https://lore.kernel.org/linux-mm/6edebc2b-5f5a-4b9c-9a4c-564310acee1b@kernel.org [2] >>> Acked-by: Vlastimil Babka (SUSE) >>> Signed-off-by: Harry Yoo (Oracle) >>> Link: https://lore.kernel.org/linux-mm/872bd673-3d45-4111-8a41-31185db3ece5@kernel.org >>> Signed-off-by: Harry Yoo (Oracle) >>> Link: https://lore.kernel.org/linux-mm/6811cc17-8ee4-48c8-8cbf-6bf4d9f98162@kernel.org [1] >>> Link: https://lore.kernel.org/linux-mm/40591888-3a87-433e-b3d2-cda1cab543be@kernel.org [2] >>> Suggested-by: Vlastimil Babka (SUSE) >>> Signed-off-by: Harry Yoo (Oracle) >>> Signed-off-by: Harry Yoo (Oracle) >>> Signed-off-by: Harry Yoo (Oracle) >> >> Wonder what produced this weird block of assorted trailers? "b4 prep >> --compare-to vX" never did that for me? > > Interesting. I checked it again with `b4 prep --compare-to v4`, but the > command didn't produce this. Looking at the cover letter > `b4 prep --edit-cover` It's not even there. > > Probably it was produced during b4 send --no-sign? hmm... Hmm let's see if it ever happens again. >>> --- >>> Harry Yoo (Oracle) (8): >>> mm/slab, slub_kunit: register kprobe to trigger _nolock APIs >>> mm/slab: handle the !allow_spin case in kfree_rcu_sheaf() >>> mm/slab: use call_rcu() in unknown context if irqs are enabled >>> mm/slab: extend deferred free mechanism to handle rcu sheaves >>> mm/slab: allow kfree_rcu_sheaf() on PREEMPT_RT >>> mm/slab: introduce struct kvfree_rcu_head for kvfree_rcu batching >>> mm/slab: introduce kfree_rcu_nolock() >>> slub_kunit: extend the test for kfree_rcu_nolock() >>> >>> include/linux/rcupdate.h | 32 ++++++- >>> include/linux/slab.h | 16 +--- >>> include/linux/types.h | 8 ++ >>> include/trace/events/rcu.h | 2 +- >>> lib/tests/slub_kunit.c | 190 ++++++++++++++++++++++++++++----------- >>> mm/slab.h | 52 ++++++++++- >>> mm/slab_common.c | 81 +++++++++++++---- >>> mm/slub.c | 220 ++++++++++++++++++++++++++++----------------- >>> 8 files changed, 433 insertions(+), 168 deletions(-) >> >> Applied to slab/for-7.3/kfree_rcu_nolock and merged go slab/for-next, thanks! > > Thanks a lot! > >> Used slab/for-next-fixes as a base for a better topic branch indepdencence. > > Ah, I see. thanks. > > So slab/for-next is not a good base unless it depends too much on > existing commits on the branch? > > And usually it's better to use the base (slab/for-next-fixes, > in this case) of slab/for-next as a base? Yeah. Hopefully we'll figure out some documented guidelines for this in the upcoming mm-next meetings. >>> --- >>> base-commit: ffc64805cebac330b2a60b2f1f144fcc35b8ab46 >>> change-id: 20260615-kfree_rcu_nolock-e5502555992f >>> >>> Best regards, >