From b90ca8badbd11488e5f762346b028666808164e7 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 30 Jul 2021 12:24:33 +0100 Subject: sched: Introduce task_struct::user_cpus_ptr to track requested affinity In preparation for saving and restoring the user-requested CPU affinity mask of a task, add a new cpumask_t pointer to 'struct task_struct'. If the pointer is non-NULL, then the mask is copied across fork() and freed on task exit. Signed-off-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Valentin Schneider Link: https://lore.kernel.org/r/20210730112443.23245-7-will@kernel.org --- include/linux/sched.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 50db9496c99d..2c5d638daaad 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -748,6 +748,7 @@ struct task_struct { unsigned int policy; int nr_cpus_allowed; const cpumask_t *cpus_ptr; + cpumask_t *user_cpus_ptr; cpumask_t cpus_mask; void *migration_pending; #ifdef CONFIG_SMP @@ -1706,6 +1707,8 @@ extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_ #ifdef CONFIG_SMP extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); +extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); +extern void release_user_cpus_ptr(struct task_struct *p); #else static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) { @@ -1716,6 +1719,16 @@ static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpuma return -EINVAL; return 0; } +static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) +{ + if (src->user_cpus_ptr) + return -EINVAL; + return 0; +} +static inline void release_user_cpus_ptr(struct task_struct *p) +{ + WARN_ON(p->user_cpus_ptr); +} #endif extern int yield_to(struct task_struct *p, bool preempt); -- cgit v1.2.3