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b=M3xCeJyxC374t2syxCskrtuPvHfNZvR/I4iyLwMEsBtz/zttNVyoZ9ptm2tKNYIxN GR9DbP8QXbXo7LTCARFObUPM+hJIGLuDCJVkzdNURIlY5hiOYGPI1cS69zU39QWf0X LqnOijrOX2t9wtLnJplVBkY4I1RbWGVYH2JdE/X+C79IsPBq4Ruh0pTBOWCLjDl2eA DLXY3SvkoKyAULHBwASeZjoFVEp3N+OIIYY/WGI8h6D92TyDNj8oXnFC21el3csVT1 1Pr5Hnsu13Yx4GtRLEbx0LCV0jFweJpYKi1MPv49cMVKNbz0fwrXdlOto5iUrjjCwk vEapF2nyQa4lA== Date: Fri, 22 May 2026 14:04:02 +0100 From: Lorenzo Stoakes To: ranxiaokai627@163.com Cc: akpm@linux-foundation.org, baolin.wang@linux.alibaba.com, hughd@google.com, leitao@debian.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ran.xiaokai@zte.com.cn Subject: Re: [PATCH v2 1/2] mm: huge_memory: refactor thpsize_shmem_enabled_store() with sysfs_match_string() Message-ID: References: <20260518110816.79be9a7c71777c1876b0019d@linux-foundation.org> <20260520102922.63737-1-ranxiaokai627@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260520102922.63737-1-ranxiaokai627@163.com> X-Rspamd-Queue-Id: 9D67D4000C X-Stat-Signature: i99iumg87bxmcat6ztyrm337yaifm7e6 X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1779455048-707136 X-HE-Meta: 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 GGueaQQa XxwnQ6bUpAlNO5p0DkaCDhObDQyEslkHL0tmSvQi42BSk8j0ShzsScBi+e/6PVbtaK0mLOy1XxL1UNWhEY/61Lcc4HL8o32Oi4wamRQ7gaaFX3snsod0EVGW8gcX/gu6xSExOHjCrykDYkUt/OdW/54I5E8lvFLxNcpScmuaH3HdkY4hbUDAlQuAwsxSq7PDNAdqVLkyj3c0CF8ik9K7GdLF02o+iJdVT0Bq9iX+6Cz9yoFf2wric4PdCvo0FWufhkLPFnMYHsnv7kWhUtvuP3X0r8z+bRI2el/T3HqiBOZ8msBzJT7ln8Gej6QPs8HvEQ4iUqycoO4ZVDche8sLCedNPC8fxRP5VJlG0MsQK5Iqo4Jpl+JYQj+X3OHl7oVxH6+NDZWKx+8US2qQRrWV0QAmyMg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, May 20, 2026 at 10:29:22AM +0000, ranxiaokai627@163.com wrote: > >On Thu, 14 May 2026 09:26:39 +0000 ranxiaokai627@163.com wrote: > > > >> Thanks for the detailed and thoughtful review! I'll fix this as > >> suggested in the next version. > > > >AI review is asking about a couple of atomicity issues - please check it out? > > https://sashiko.dev/#/patchset/20260513094508.50888-1-ranxiaokai627@163.com > > The huge_shmem_orders_xxx global variables are of type unsigned long, > which is 32-bit even on 32-bit systems. There is no reason for the > store in __test_and_set_bit() to be split into two instructions, > so I do not think this introduces a torn write issue. Yep agreed, this doesn't look like a real issue. > > David also mentioned this optimization here: > https://lore.kernel.org/all/4f2abf42-983f-4cc2-92f5-c81827e7b7e2@kernel.org/ > Yup, I think it's fine as is! Thanks, Lorenzo