diff options
| -rw-r--r-- | include/linux/sched.h | 1 | ||||
| -rw-r--r-- | kernel/sched/core.c | 10 | ||||
| -rw-r--r-- | kernel/sched/deadline.c | 10 |
3 files changed, 16 insertions, 5 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index cc66f2615a6d..158f4c2dd852 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1102,6 +1102,7 @@ struct sched_dl_entity { */ u64 dl_runtime; /* maximum runtime for each instance */ u64 dl_deadline; /* relative deadline of each instance */ + u64 dl_period; /* separation of two instances (period) */ /* * Actual scheduling parameters. Initialized with the values above, diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 548cc04aee45..069230b5c3fb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1723,6 +1723,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); p->dl.dl_runtime = p->dl.runtime = 0; p->dl.dl_deadline = p->dl.deadline = 0; + p->dl.dl_period = 0; p->dl.flags = 0; INIT_LIST_HEAD(&p->rt.run_list); @@ -3026,6 +3027,7 @@ __setparam_dl(struct task_struct *p, const struct sched_attr *attr) init_dl_task_timer(dl_se); dl_se->dl_runtime = attr->sched_runtime; dl_se->dl_deadline = attr->sched_deadline; + dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline; dl_se->flags = attr->sched_flags; dl_se->dl_throttled = 0; dl_se->dl_new = 1; @@ -3067,19 +3069,23 @@ __getparam_dl(struct task_struct *p, struct sched_attr *attr) attr->sched_priority = p->rt_priority; attr->sched_runtime = dl_se->dl_runtime; attr->sched_deadline = dl_se->dl_deadline; + attr->sched_period = dl_se->dl_period; attr->sched_flags = dl_se->flags; } /* * This function validates the new parameters of a -deadline task. * We ask for the deadline not being zero, and greater or equal - * than the runtime. + * than the runtime, as well as the period of being zero or + * greater than deadline. */ static bool __checkparam_dl(const struct sched_attr *attr) { return attr && attr->sched_deadline != 0 && - (s64)(attr->sched_deadline - attr->sched_runtime) >= 0; + (attr->sched_period == 0 || + (s64)(attr->sched_period - attr->sched_deadline) >= 0) && + (s64)(attr->sched_deadline - attr->sched_runtime ) >= 0; } /* diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 21f58d261134..3958bc576d67 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -289,7 +289,7 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * arbitrary large. */ while (dl_se->runtime <= 0) { - dl_se->deadline += dl_se->dl_deadline; + dl_se->deadline += dl_se->dl_period; dl_se->runtime += dl_se->dl_runtime; } @@ -329,9 +329,13 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se) * * This function returns true if: * - * runtime / (deadline - t) > dl_runtime / dl_deadline , + * runtime / (deadline - t) > dl_runtime / dl_period , * * IOW we can't recycle current parameters. + * + * Notice that the bandwidth check is done against the period. For + * task with deadline equal to period this is the same of using + * dl_deadline instead of dl_period in the equation above. */ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) { @@ -355,7 +359,7 @@ static bool dl_entity_overflow(struct sched_dl_entity *dl_se, u64 t) * of anything below microseconds resolution is actually fiction * (but still we want to give the user that illusion >;). */ - left = (dl_se->dl_deadline >> 10) * (dl_se->runtime >> 10); + left = (dl_se->dl_period >> 10) * (dl_se->runtime >> 10); right = ((dl_se->deadline - t) >> 10) * (dl_se->dl_runtime >> 10); return dl_time_before(right, left); |