From 99d2592023e5d0a31f5f5a83c694df48239a1e6c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 15 Dec 2025 17:52:15 +0100 Subject: rseq: Implement sys_rseq_slice_yield() Provide a new syscall which has the only purpose to yield the CPU after the kernel granted a time slice extension. sched_yield() is not suitable for that because it unconditionally schedules, but the end of the time slice extension is not required to schedule when the task was already preempted. This also allows to have a strict check for termination to catch user space invoking random syscalls including sched_yield() from a time slice extension region. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Mathieu Desnoyers Acked-by: Arnd Bergmann Link: https://patch.msgid.link/20251215155708.929634896@linutronix.de --- include/uapi/asm-generic/unistd.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/uapi/asm-generic') diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 942370b3f5d2..a627acc8fb5f 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -860,8 +860,11 @@ __SYSCALL(__NR_file_setattr, sys_file_setattr) #define __NR_listns 470 __SYSCALL(__NR_listns, sys_listns) +#define __NR_rseq_slice_yield 471 +__SYSCALL(__NR_rseq_slice_yield, sys_rseq_slice_yield) + #undef __NR_syscalls -#define __NR_syscalls 471 +#define __NR_syscalls 472 /* * 32 bit systems traditionally used different -- cgit