diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2026-01-21 14:21:51 +0100 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-01-22 11:11:20 +0100 |
| commit | e1d7f54900f1e1d3003a85b78cd7105a64203ff7 (patch) | |
| tree | 51eed0ed4bc06cb19ebc43e37bc481e7286df577 /Documentation | |
| parent | d6200245c75e832af2087bc60ba2e6641a90eee9 (diff) | |
rseq: Move slice_ext_nsec to debugfs
Move changing the slice ext duration to debugfs, a sliglty less permanent
interface.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260121143207.923520192@infradead.org
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/sysctl/kernel.rst | 11 | ||||
| -rw-r--r-- | Documentation/userspace-api/rseq.rst | 4 |
2 files changed, 3 insertions, 12 deletions
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index b09d18e0f75b..239da22c4e28 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -1248,17 +1248,6 @@ reboot-cmd (SPARC only) ROM/Flash boot loader. Maybe to tell it what to do after rebooting. ??? -rseq_slice_extension_nsec -========================= - -A task can request to delay its scheduling if it is in a critical section -via the prctl(PR_RSEQ_SLICE_EXTENSION_SET) mechanism. This sets the maximum -allowed extension in nanoseconds before scheduling of the task is enforced. -Default value is 10000ns (10us). The possible range is 10000ns (10us) to -50000ns (50us). - -This value has a direct correlation to the worst case scheduling latency; -increment at your own risk. sched_energy_aware ================== diff --git a/Documentation/userspace-api/rseq.rst b/Documentation/userspace-api/rseq.rst index e1fdb0d5ce69..29af6c300396 100644 --- a/Documentation/userspace-api/rseq.rst +++ b/Documentation/userspace-api/rseq.rst @@ -79,7 +79,9 @@ slice extension by setting rseq::slice_ctrl::request to 1. If the thread is interrupted and the interrupt results in a reschedule request in the kernel, then the kernel can grant a time slice extension and return to userspace instead of scheduling out. The length of the extension is -determined by the ``rseq_slice_extension_nsec`` sysctl. +determined by debugfs:rseq/slice_ext_nsec. The default value is 10 usec; which +is the minimum value. It can be incremented to 50 usecs, however doing so +can/will affect the minimum scheduling latency. The kernel indicates the grant by clearing rseq::slice_ctrl::request and setting rseq::slice_ctrl::granted to 1. If there is a reschedule of the |