On 11/12/2025 07:55, Thomas Gleixner wrote: > I have a suspicion that it is TIF_NOTIFY_RESUME. If that's the case > you're seing the RSEQ overhead, which should be completely gone with the > rewrite that got just merged into Linus tree.
I don't think this is related. This patch inlines syscall_exit_work(), which is called if some flag in SYSCALL_WORK_EXIT is set. This includes syscall-specific stuff like tracing and singlestep. TIF_NOTIFY_RESUME is part of EXIT_TO_USER_MODE_WORK, handled in exit_to_user_mode_prepare(), and isn't specific to syscall handling. - Kevin

