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 /kernel/sys.c | |
| 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 'kernel/sys.c')
| -rw-r--r-- | kernel/sys.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/sys.c b/kernel/sys.c index 8b58eece4e58..af71987df81c 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -53,6 +53,7 @@ #include <linux/time_namespace.h> #include <linux/binfmts.h> #include <linux/futex.h> +#include <linux/rseq.h> #include <linux/sched.h> #include <linux/sched/autogroup.h> @@ -2868,6 +2869,11 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, case PR_FUTEX_HASH: error = futex_hash_prctl(arg2, arg3, arg4); break; + case PR_RSEQ_SLICE_EXTENSION: + if (arg4 || arg5) + return -EINVAL; + error = rseq_slice_extension_prctl(arg2, arg3); + break; default: trace_task_prctl_unknown(option, arg2, arg3, arg4, arg5); error = -EINVAL; |