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Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , Zi Yan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH 1/8] mm: use zone lock guard in reserve_highatomic_pageblock() Message-ID: <20260313083653.GI606826@noisy.programming.kicks-ass.net> References: <20260306095336.a79fcc869a7f6d2b2e97501b@linux-foundation.org> <20260306130052.7da8eab3@gandalf.local.home> <20260307131641.GX606826@noisy.programming.kicks-ass.net> <20260309164516.GE606826@noisy.programming.kicks-ass.net> <69b34efd5bd1a_213210038@dwillia2-mobl4.notmuch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <69b34efd5bd1a_213210038@dwillia2-mobl4.notmuch> X-Rspam-User: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 2382A160004 X-Stat-Signature: 4jjbsa9jkr5w96t7hzxyq4mmnzqhcu4x X-HE-Tag: 1773391021-591204 X-HE-Meta: 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 6A3zmddj 1Wml+I5jtOITWTU2Hh8rvMu7TkiOpgjYQkIWBkjzpMUOUDQFAX+IEF898IK4MHj8e0XZFNrXmJLZP9zaN3WS6n2U3I79Zcry9vA2gezLcCdTXXOJjI9CiUgRsrPwFxHaeU9uO3rpxfY1kKi0ComIzLvlI1SFv1yI9vSbzZhavRmtLJVmG/vnhOou+1pqBAoFLvOP+SjE3CJfYEysgL2+UH8CYyMUAK4rnoZC5k1mP39zlQ9HBzUWI2S56Uwz2yEuld4fKceoUpgTImQ4nFdI8PqJGXhg5svCRYAiL Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Mar 12, 2026 at 04:40:45PM -0700, Dan Williams wrote: > Peter Zijlstra wrote: > [..] > > However, looking at things again, I think we can get rid of that > > unconditional __GUARD_IS_ERR(), something like the below, Dan? > > I think it makes sense, do not make everyone pay the cost of > __GUARD_IS_ERR() at least until a better __GUARD_IS_ERR() comes along. > > I gave the below a run through the CXL subsystem tests which uses > conditional guards quite a bit. Worked fine, and looks good to me. > > So feel free to add a "tested by" from me. Not putting the actual tag > here so that b4 does not slurp a tag for the wrong patchset. Excellent, thanks for having a look. Let me go write it up.