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/uapi/linux/prctl.h | |
| 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/uapi/linux/prctl.h')
| -rw-r--r-- | include/uapi/linux/prctl.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 51c4e8c82b1e..79944b7ae50a 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -386,4 +386,14 @@ struct prctl_mm_map { # define PR_FUTEX_HASH_SET_SLOTS 1 # define PR_FUTEX_HASH_GET_SLOTS 2 +/* RSEQ time slice extensions */ +#define PR_RSEQ_SLICE_EXTENSION 79 +# define PR_RSEQ_SLICE_EXTENSION_GET 1 +# define PR_RSEQ_SLICE_EXTENSION_SET 2 +/* + * Bits for RSEQ_SLICE_EXTENSION_GET/SET + * PR_RSEQ_SLICE_EXT_ENABLE: Enable + */ +# define PR_RSEQ_SLICE_EXT_ENABLE 0x01 + #endif /* _LINUX_PRCTL_H */ |