From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D12E7C43458 for ; Fri, 3 Jul 2026 09:39:09 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C3E0D6B00B6; Fri, 3 Jul 2026 05:39:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C15B36B00B7; Fri, 3 Jul 2026 05:39:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B2C246B00B8; Fri, 3 Jul 2026 05:39:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 79F446B00B6 for ; Fri, 3 Jul 2026 05:39:08 -0400 (EDT) Received: from smtpin27.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 0C3B312037F for ; Fri, 3 Jul 2026 09:39:08 +0000 (UTC) X-FDA: 84946966776.27.08ED0B3 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf31.hostedemail.com (Postfix) with ESMTP id 5ADF220004 for ; Fri, 3 Jul 2026 09:39:06 +0000 (UTC) Authentication-Results: imf31.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=IIdjRc2F; spf=pass (imf31.hostedemail.com: domain of harry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=harry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1783071546; b=F4Vg5nvvyCVsXgb/sY7cpW2SYgEelW3iX2sfWFH5YIP6J3l1ABFP4RIpVEAoJQh4Mh4xvs l4lfLWGFbPYgKfXg6KD37JJzaNWeT3wEqL6tOKVLPR0QjuHeeV/TsGVF58nChfkTJPvzUL GkKyD32dP3qek/KFCaewWxlhZP3aNXA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1783071546; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/jgWAf5SwPzlqhJKQG2/7AalkDHZJDG2niv0fSajwEU=; b=jnbd98OLhKrmBzaHgyXhG3XGHhG+WPTke7I5yuBYwTAoE759onysj8YBzdy85T1VFi/OAH 6oFIKBE0Ds+yTuf8wU6yf06oNt16lxmPyKBo8ID7Re0xsiPBvK7sfkG+3FN6kYaEn+NXSU VgRUuAkagAmyUlp7GPXdVIETCYkbmf4= ARC-Authentication-Results: i=1; imf31.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=IIdjRc2F; spf=pass (imf31.hostedemail.com: domain of harry@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=harry@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 9081C40B02; Fri, 3 Jul 2026 09:39:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10FAB1F000E9; Fri, 3 Jul 2026 09:38:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783071545; bh=/jgWAf5SwPzlqhJKQG2/7AalkDHZJDG2niv0fSajwEU=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=IIdjRc2Ff/MhGB0w5/vA6UjULptWQXsppua/eAUQJfQd5NdXeRV+p01OWY8Bt3MPx 4cCwYAFNdOfbaGdRUnh8JC/PEGaL921tNnsYvSZayZ03ymB3aeVliby82ll+FWzCaQ SIsx2dDAR0T1X9mG4D83sJAUOi+NrbIxNf5WZxypCZ98bPyoxgMMd50YEOi7wKPZTQ u7Q9/JcQ+aC7Aao4EcS84uEFUJCKZOucloXKmc1GFudydK99rNNkqs6AH6O1LYyaqq 8ssYDoFNn58jqKcwT3gORSPDYeyUS9bqj8DnoMb93ezoxbBc77dlKC0CeNbveMZYb2 A36yiTH0mN0NA== Message-ID: <21ec3b5e-8e8a-4f8c-aad9-ff9b77bd6d6e@kernel.org> Date: Fri, 3 Jul 2026 18:38:39 +0900 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 18/18] mm: factor out can_spin_trylock() To: Brendan Jackman , Andrew Morton , Vlastimil Babka , 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: 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 References: <20260702-alloc-trylock-v4-0-0af8ff387e80@google.com> <20260702-alloc-trylock-v4-18-0af8ff387e80@google.com> Content-Language: en-US From: Harry Yoo In-Reply-To: <20260702-alloc-trylock-v4-18-0af8ff387e80@google.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------hFDyml7LY0WmvWczM3Ou39Mo" X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 5ADF220004 X-Stat-Signature: 7mhg7agrmui6iw4u8ak7tie4pr9ozon5 X-HE-Tag: 1783071546-309010 X-HE-Meta: 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 NgGNJCh6 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --------------hFDyml7LY0WmvWczM3Ou39Mo Content-Type: multipart/mixed; boundary="------------EMNg7VfEL9bzN6yUIrxUi2BK"; protected-headers="v1" From: Harry Yoo To: Brendan Jackman , Andrew Morton , Vlastimil Babka , 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: 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 Message-ID: <21ec3b5e-8e8a-4f8c-aad9-ff9b77bd6d6e@kernel.org> Subject: Re: [PATCH v4 18/18] mm: factor out can_spin_trylock() References: <20260702-alloc-trylock-v4-0-0af8ff387e80@google.com> <20260702-alloc-trylock-v4-18-0af8ff387e80@google.com> In-Reply-To: <20260702-alloc-trylock-v4-18-0af8ff387e80@google.com> --------------EMNg7VfEL9bzN6yUIrxUi2BK Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 7/2/26 6:49 PM, Brendan Jackman wrote: > Deduplicate checks for whether the current context is safe for > spin_trylock(). >=20 > Does this function really belong in mm/internal.h or is it generic? Not= > sure. If someone ends up duplicating this logic elsewhere in the kernel= , > that would be a shame. Wondering what BPF has been doing about it... > But goes in some generic header, someone treats > it as documentation about where it's guaranteed safe to spin_trylock(),= > and then it emerges that there are other subtle preconditions that > didn't affect the mm usecase, that would be worse. So, just be > conservative and keep it local. But yeah, agreed. > Suggested-by: Harry Yoo > Link: https://lore.kernel.org/all/397859cb-b127-4cc6-9c71-044afc99bf0c@= kernel.org/ > Signed-off-by: Brendan Jackman > --- Reviewed-by: Harry Yoo (Oracle) Thanks! --=20 Cheers, Harry / Hyeonggon --------------EMNg7VfEL9bzN6yUIrxUi2BK-- --------------hFDyml7LY0WmvWczM3Ou39Mo Content-Type: application/pgp-signature; name="OpenPGP_signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="OpenPGP_signature.asc" -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQQQ1ub6gR5ogjaKRmOGXBN6rc5S1gUCakeDHwAKCRCGXBN6rc5S 1qOoAP9X/oz3Te45ijX+oZqnExbf3F/cLVlMnCzGQzkprL5sGwD/VnLjX0AY95bV /SjSfOk7aMvj/cla9N9FEs2kf6hCUQo= =jFVY -----END PGP SIGNATURE----- --------------hFDyml7LY0WmvWczM3Ou39Mo--