Sebastian Andrzej Siewior 3bd3706251 sched/core: Provide a pointer to the valid CPU mask ... In commit: 4b53a3412d ("sched/core: Remove the tsk_nr_cpus_allowed() wrapper") the tsk_nr_cpus_allowed() wrapper was removed. There was not much difference in !RT but in RT we used this to implement migrate_disable(). Within a migrate_disable() section the CPU mask is restricted to single CPU while the "normal" CPU mask remains untouched. As an alternative implementation Ingo suggested to use: struct task_struct { const cpumask_t *cpus_ptr; cpumask_t cpus_mask; }; with t->cpus_ptr = &t->cpus_mask; In -RT we then can switch the cpus_ptr to: t->cpus_ptr = &cpumask_of(task_cpu(p)); in a migration disabled region. The rules are simple: - Code that 'uses' ->cpus_allowed would use the pointer. - Code that 'modifies' ->cpus_allowed would use the direct mask. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20190423142636.14347-1-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>		2019-06-03 11:49:37 +02:00
..
core.c
ctrlmondata.c	x86/resctrl: Initialize a new resource group with default MBA values	2019-04-18 00:06:31 +02:00
internal.h	kernfs, sysfs, cgroup, intel_rdt: Support fs_context	2019-02-28 03:29:34 -05:00
Makefile	x86/resctrl: Avoid confusion over the new X86_RESCTRL config	2019-02-02 10:34:52 +01:00
monitor.c	x86/resctrl: Remove unused variable	2019-03-24 22:09:27 +01:00
pseudo_lock_event.h
pseudo_lock.c	sched/core: Provide a pointer to the valid CPU mask	2019-06-03 11:49:37 +02:00
rdtgroup.c	x86/resctrl: Initialize a new resource group with default MBA values	2019-04-18 00:06:31 +02:00