diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-09-17 10:38:30 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-11-10 18:38:59 +0100 |
| commit | af449901b84c98cbd84a0113223ba3bcfcb12a26 (patch) | |
| tree | 0580fcc4d04ef7ebaa77a658cba36203668c3e44 /lib/smp_processor_id.c | |
| parent | 9cfc3e18adb0362533e911bf3ce6ec8c821cfccc (diff) | |
| download | lwn-af449901b84c98cbd84a0113223ba3bcfcb12a26.tar.gz lwn-af449901b84c98cbd84a0113223ba3bcfcb12a26.zip | |
sched: Add migrate_disable()
Add the base migrate_disable() support (under protest).
While migrate_disable() is (currently) required for PREEMPT_RT, it is
also one of the biggest flaws in the system.
Notably this is just the base implementation, it is broken vs
sched_setaffinity() and hotplug, both solved in additional patches for
ease of review.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Link: https://lkml.kernel.org/r/20201023102346.818170844@infradead.org
Diffstat (limited to 'lib/smp_processor_id.c')
| -rw-r--r-- | lib/smp_processor_id.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/lib/smp_processor_id.c b/lib/smp_processor_id.c index 525222e4f409..faaa927ac2c8 100644 --- a/lib/smp_processor_id.c +++ b/lib/smp_processor_id.c @@ -26,6 +26,11 @@ unsigned int check_preemption_disabled(const char *what1, const char *what2) if (current->nr_cpus_allowed == 1) goto out; +#if defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT) + if (current->migration_disabled) + goto out; +#endif + /* * It is valid to assume CPU-locality during early bootup: */ |