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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 2DA89100002 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: j9iess8s4i51oymhsma3ne3ffcg85fbb X-HE-Tag: 1729842138-128688 X-HE-Meta: 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 XVvoJw0p 92QfG+e7UDUr2rYbhCVFUnwliNrMJowRLhXNNWzm/86krF/+IbXn57VQqQsTy/fKPSZk8M5+EDJ+8VuQnUwqtGrjmzAMoscWw/uu4ZRLX7/WzwqWyX7OrnhwaMpHGeaU/ToT4ww9Dr4FsJ5ZbBKQAXi3VTVSh3anCKWQn29RdQWYNg263cEZqOAwh4dYmBHmynIXS7BdTi/e2yMi+RdhpjqMa1gJPCtNCHRsiUQI+qvAWo0NPoFC0y3qwOgnFUtgHMZ9lTbLuXNZG6+H6V0zMpPVBjQO0igufpuRjoPzEa+B6k/UpL9azpxYBKw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Oct 23, 2024 at 04:42:36PM -0700, Christoph Lameter (Ampere) wrote: > On Wed, 23 Oct 2024, Peter Zijlstra wrote: > > > > I doubt anybody will notice, and smp_load_acquire() is the future. Any > > > architecture that does badly on it just doesn't matter (and, as > > > mentioned, I don't think they even exist - "smp_rmb()" is generally at > > > least as expensive). > > > > Do we want to do the complementing patch and make write_seqcount_end() > > use smp_store_release() ? > > > > I think at least ARM (the 32bit thing) has wmb but uses mb for > > store_release. But I also think I don't really care about that. > > The proper instruction would be something like > > atomic_inc_release(&seqcount) It would not be, making the increment itself atomic would make the whole thing far more expensive.