| Message ID | 20210602164719.31777-13-will@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add support for 32-bit tasks on asymmetric AArch32 systems | expand |
On 6/2/21 6:47 PM, Will Deacon wrote: > In preparation for restricting the affinity of a task during execve() > on arm64, introduce a new task_cpus_dl_admissible() helper function to > give an indication as to whether the restricted mask is admissible for > a deadline task. > > Signed-off-by: Will Deacon <will@kernel.org> > --- > include/linux/sched.h | 6 ++++++ > kernel/sched/core.c | 44 +++++++++++++++++++++++++++---------------- > 2 files changed, 34 insertions(+), 16 deletions(-) > > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 91a6cfeae242..9b17d8cfa6ef 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1691,6 +1691,7 @@ extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new > 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); > +extern bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask); > extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); > extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); > #else > @@ -1713,6 +1714,11 @@ static inline void release_user_cpus_ptr(struct task_struct *p) > { > WARN_ON(p->user_cpus_ptr); > } > + > +static inline bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) > +{ > + return true; > +} > #endif > > extern int yield_to(struct task_struct *p, bool preempt); > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 58e2cf7520c0..b4f8dc18ae11 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6933,6 +6933,31 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, > return retval; > } > > +#ifdef CONFIG_SMP > +bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) Would you mind renaming it to dl_task_check_affinity(), in the case of a v9? It will look coherent with dl_task_can_attach()... Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Thanks! -- Daniel
On Thu, Jun 03, 2021 at 11:43:08AM +0200, Daniel Bristot de Oliveira wrote: > On 6/2/21 6:47 PM, Will Deacon wrote: > > In preparation for restricting the affinity of a task during execve() > > on arm64, introduce a new task_cpus_dl_admissible() helper function to > > give an indication as to whether the restricted mask is admissible for > > a deadline task. > > > > Signed-off-by: Will Deacon <will@kernel.org> > > --- > > include/linux/sched.h | 6 ++++++ > > kernel/sched/core.c | 44 +++++++++++++++++++++++++++---------------- > > 2 files changed, 34 insertions(+), 16 deletions(-) > > > > diff --git a/include/linux/sched.h b/include/linux/sched.h > > index 91a6cfeae242..9b17d8cfa6ef 100644 > > --- a/include/linux/sched.h > > +++ b/include/linux/sched.h > > @@ -1691,6 +1691,7 @@ extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new > > 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); > > +extern bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask); > > extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); > > extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); > > #else > > @@ -1713,6 +1714,11 @@ static inline void release_user_cpus_ptr(struct task_struct *p) > > { > > WARN_ON(p->user_cpus_ptr); > > } > > + > > +static inline bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) > > +{ > > + return true; > > +} > > #endif > > > > extern int yield_to(struct task_struct *p, bool preempt); > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > > index 58e2cf7520c0..b4f8dc18ae11 100644 > > --- a/kernel/sched/core.c > > +++ b/kernel/sched/core.c > > @@ -6933,6 +6933,31 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, > > return retval; > > } > > > > +#ifdef CONFIG_SMP > > +bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) > > Would you mind renaming it to dl_task_check_affinity(), in the case of a v9? It > will look coherent with dl_task_can_attach()... Of course! I struggled with the naming myself, and your suggestion is much better. > Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Cheers! Will
diff --git a/include/linux/sched.h b/include/linux/sched.h index 91a6cfeae242..9b17d8cfa6ef 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1691,6 +1691,7 @@ extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new 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); +extern bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask); extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); #else @@ -1713,6 +1714,11 @@ static inline void release_user_cpus_ptr(struct task_struct *p) { WARN_ON(p->user_cpus_ptr); } + +static inline bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) +{ + return true; +} #endif extern int yield_to(struct task_struct *p, bool preempt); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 58e2cf7520c0..b4f8dc18ae11 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6933,6 +6933,31 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, return retval; } +#ifdef CONFIG_SMP +bool task_cpus_dl_admissible(struct task_struct *p, const struct cpumask *mask) +{ + bool ret; + + /* + * If the task isn't a deadline task or admission control is + * disabled then we don't care about affinity changes. + */ + if (!task_has_dl_policy(p) || !dl_bandwidth_enabled()) + return true; + + /* + * Since bandwidth control happens on root_domain basis, + * if admission test is enabled, we only admit -deadline + * tasks allowed to run on all the CPUs in the task's + * root_domain. + */ + rcu_read_lock(); + ret = cpumask_subset(task_rq(p)->rd->span, mask); + rcu_read_unlock(); + return ret; +} +#endif + static int __sched_setaffinity(struct task_struct *p, const struct cpumask *mask) { @@ -6950,23 +6975,10 @@ __sched_setaffinity(struct task_struct *p, const struct cpumask *mask) cpuset_cpus_allowed(p, cpus_allowed); cpumask_and(new_mask, mask, cpus_allowed); - /* - * Since bandwidth control happens on root_domain basis, - * if admission test is enabled, we only admit -deadline - * tasks allowed to run on all the CPUs in the task's - * root_domain. - */ -#ifdef CONFIG_SMP - if (task_has_dl_policy(p) && dl_bandwidth_enabled()) { - rcu_read_lock(); - if (!cpumask_subset(task_rq(p)->rd->span, new_mask)) { - retval = -EBUSY; - rcu_read_unlock(); - goto out_free_new_mask; - } - rcu_read_unlock(); + if (!task_cpus_dl_admissible(p, new_mask)) { + retval = -EBUSY; + goto out_free_new_mask; } -#endif again: retval = __set_cpus_allowed_ptr(p, new_mask, SCA_CHECK | SCA_USER); if (retval)
In preparation for restricting the affinity of a task during execve() on arm64, introduce a new task_cpus_dl_admissible() helper function to give an indication as to whether the restricted mask is admissible for a deadline task. Signed-off-by: Will Deacon <will@kernel.org> --- include/linux/sched.h | 6 ++++++ kernel/sched/core.c | 44 +++++++++++++++++++++++++++---------------- 2 files changed, 34 insertions(+), 16 deletions(-)