diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2025-12-15 17:52:12 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-01-22 11:11:17 +0100 |
| commit | 28621ec2d46c6adf7d33a6facbd83e2fa566bd34 (patch) | |
| tree | 0142162562beb93fe3ad5695ae248ff0b74e3997 /include/linux | |
| parent | b5b8282441bc4f8f1ff505e19d566dbd7b805761 (diff) | |
rseq: Add prctl() to enable time slice extensions
Implement a prctl() so that tasks can enable the time slice extension
mechanism. This fails, when time slice extensions are disabled at compile
time or on the kernel command line and when no rseq pointer is registered
in the kernel.
That allows to implement a single trivial check in the exit to user mode
hotpath, to decide whether the whole mechanism needs to be invoked.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251215155708.858717691@linutronix.de
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/rseq.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/rseq.h b/include/linux/rseq.h index 2266f4dc77b6..3c194a02ad0a 100644 --- a/include/linux/rseq.h +++ b/include/linux/rseq.h @@ -163,4 +163,13 @@ void rseq_syscall(struct pt_regs *regs); static inline void rseq_syscall(struct pt_regs *regs) { } #endif /* !CONFIG_DEBUG_RSEQ */ +#ifdef CONFIG_RSEQ_SLICE_EXTENSION +int rseq_slice_extension_prctl(unsigned long arg2, unsigned long arg3); +#else /* CONFIG_RSEQ_SLICE_EXTENSION */ +static inline int rseq_slice_extension_prctl(unsigned long arg2, unsigned long arg3) +{ + return -ENOTSUPP; +} +#endif /* !CONFIG_RSEQ_SLICE_EXTENSION */ + #endif /* _LINUX_RSEQ_H */ |