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charset=us-ascii Content-Disposition: inline In-Reply-To: <20231025235413.597287e1@gandalf.local.home> X-Rspamd-Queue-Id: 8B03A18002C X-Rspam-User: X-Stat-Signature: w17z7yhnx5p7ir7r36npwx33ukq97k9x X-Rspamd-Server: rspam03 X-HE-Tag: 1698318029-2664 X-HE-Meta: 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 iCoo+81t LtKdNWoGdz2tVFrObBzK7ONuLTvCqlhS22YYZi47phmhu4cX1frKDxi80XA/f3qeLWyG05uJrWbJNYuG3vzZIiWBZXjR5s9vif6XbeDSYPLlAFXyLt8tAXJ/wBCkLd8A9b8QkTsA4Pu8QKMs= 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 25, 2023 at 11:54:13PM -0400, Steven Rostedt wrote: > static void extend(void) > { > rseq_map.cr_flags = 1; > } > > static void unextend(void) > { > unsigned long prev; > > prev = xchg(&rseq_map.cr_flags, 0); So you complain about overhead and then you add one of the most expensive ops possible here? xchg has an implicit LOCK prefix and you really don't need LOCK prefix here. > if (prev & 2) { > tracefs_printf(NULL, "Yield!\n"); > sched_yield(); > } > }