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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 26E58180019 X-Stat-Signature: 3s7xca5k6szwhba3nsanw6jnfy7iiokb X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1739216603-718786 X-HE-Meta: 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 QB2cpalh QiuC6YojWYN50G1DS3svoQ/15fWGfOVqkGKNz5o7VBZHJTmuaRXMyfXmL6Ond9sbTHXNjlmAfcv6JKDh9PVUZwsDRRFN2EV2rc7iCuriDv5IOZun5laHOFVRcG7CLkAsoC2T5jyJKc7RYhqc/YZARG+qMyd4StgJrd4m04LDItX6i5j6r7Lm/hHbqt+/Kc0HtSFHM/oBA2VfxpyMW1UTKX7lyo7BLzOhzm9u1a5On+Lf4P40nGQqxRKWuLv2zp+uOkeXEAeMsZrQHaXJAoHo53on/LRSrX/ngBbr4zphWLK9GomjyvwcauLWgh/r8VbgmBtsM 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 Thu, 6 Feb 2025 14:44:08 +0100 Sebastian Andrzej Siewior wrote: > I did add a scheduling point in rt_spin_unlock() if LAZY was set and > based on few tests it was something between noise and worse. It seems > that "run to completion" is better than interrupt the kernel in the > middle whatever it is doing. "Don't preempt the lock owner" is already > handled by LAZY with the scheduling point on return to userland. Does that mean that PREEMPT_RT requires a non preempt method for SCHED_OTHER for SCHED_OTHER to not hit the issues that we were originally hitting? That is, with being able to preempt spin_locks in PREEMPT_RT, running a system with PREEMPT_RT in full preemption mode will still suffer performance issues against a non PREEMPT_RT running in full preemption mode? -- Steve