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McKenney" Cc: linux-kernel@vger.kernel.org, Will Deacon , Peter Zijlstra , Alan Stern , John Stultz , Linus Torvalds , Frederic Weisbecker , Joel Fernandes , Josh Triplett , Uladzislau Rezki , Steven Rostedt , Lai Jiangshan , Zqiang , Ingo Molnar , Waiman Long , Mark Rutland , Thomas Gleixner , Vlastimil Babka , maged.michael@gmail.com, Mateusz Guzik , rcu@vger.kernel.org, linux-mm@kvack.org, lkmm@lists.linux.dev References: <20240921164210.256278-1-mathieu.desnoyers@efficios.com> <2ca589bc-2a60-48ef-95a0-d9ee4a814dea@efficios.com> From: Jonas Oberhauser In-Reply-To: <2ca589bc-2a60-48ef-95a0-d9ee4a814dea@efficios.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CM-TRANSID:GxC2BwBHqcl47fdm4VvRAQ--.57124S2 X-Coremail-Antispam: 1UD129KBjvdXoW7GFW7JF1ftF4UXr1DZry5Jwb_yoWxAwcEvw nrCa15Ar43JF4xW347JF13GrWfJrWvkr4UJw18CF47Zry5ZFnxCFn3CryIy3WfG3yUC3s0 qryrX3yUZr9xWjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbx8YFVCjjxCrM7AC8VAFwI0_Wr0E3s1l1xkIjI8I6I8E6xAIw20E Y4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwV A0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x02 67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIE14v26r4j6F4UM28EF7xvwVC2z280aVCY1x0267 AKxVW8JVW8Jr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2 j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7x kEbVWUJVW8JwACjcxG0xvEwIxGrwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AK xVW8ZVWrXwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F4 0E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_Wryl IxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxV AFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j 6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07jxCz tUUUUU= X-CM-SenderInfo: 5mrqt2oorev25kdx2v3u6k3tpzhluzxrxghudrp/ X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: ABACE40014 X-Stat-Signature: nkuwzgi49ix3pb17o7deem9rzqhu1u38 X-Rspam-User: X-HE-Tag: 1727524238-930743 X-HE-Meta: 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 vcB3DYVj qZEWRf10o8/4Bwhc/dCurBPHzL0oHw4l9BQyiHxVR10Li1jTh6p9iIAer6IhAPvkdA84fy2S0dWc8hUIbYp3e8yRXb4n1D12cenOIXMNqRDLlVFGRce/30AJ+Gke9nq+Zi9kiPEJZhJmW6Lzzoz7ZvGiop17p7kn1CsmObL9xVCknJEp7W1nYj5+yggfCZAvMoWfukFL6LNtmswtqqDm4YY9CIGMY/lY1X53bs869htoXIvY= 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: Thanks for your response, Am 9/28/2024 um 1:33 PM schrieb Mathieu Desnoyers: > > This is a userspace prototype. This will behave similarly to a userspace > spinlock in that case, which is not great in terms of CPU usage, but > should eventually unblock the waiter, unless it has a RT priority that > really prevents any progress from the emergency slot owner. > > On my TODO list, I have a bullet about integrating with sys_futex to > block on wait, wake up on slot release. I would then use the wait/wakeup > code based on sys_futex already present in liburcu. Oh, I see. I think if it is for userspace then it really should use wait/wakeup as you said. Best wishes, jonas