diff options
| author | Juri Lelli <juri.lelli@arm.com> | 2014-09-19 10:22:41 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-09-24 14:46:57 +0200 |
| commit | 91ec6778ec4f963fcb2c2793610919b572f633b0 (patch) | |
| tree | 5f83a51e7a10de536ad1b83fecf3e5d4344d0d17 /kernel | |
| parent | a5e7be3b28a235108c59561bea55eea1072b23b0 (diff) | |
| download | blackbird-op-linux-91ec6778ec4f963fcb2c2793610919b572f633b0.tar.gz blackbird-op-linux-91ec6778ec4f963fcb2c2793610919b572f633b0.zip | |
sched/deadline: Fix inter- exclusive cpusets migrations
Users can perform clustered scheduling using the cpuset facility.
After an exclusive cpuset is created, task migrations happen only
between CPUs belonging to the same cpuset. Inter- cpuset migrations
can only happen when the user requires so, moving a task between
different cpusets. This behaviour is broken in SCHED_DEADLINE, as
currently spurious inter- cpuset migration may happen without user
intervention.
This patch fix the problem (and shuffles the code a bit to improve
clarity).
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: raistlin@linux.it
Cc: michael@amarulasolutions.com
Cc: fchecconi@gmail.com
Cc: daniel.wagner@bmw-carit.de
Cc: vincent@legout.info
Cc: luca.abeni@unitn.it
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1411118561-26323-4-git-send-email-juri.lelli@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/cpudeadline.c | 4 | ||||
| -rw-r--r-- | kernel/sched/deadline.c | 7 |
2 files changed, 8 insertions, 3 deletions
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index bd95963dae80..539ca3ce071b 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -107,9 +107,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, int best_cpu = -1; const struct sched_dl_entity *dl_se = &p->dl; - if (later_mask && cpumask_and(later_mask, cp->free_cpus, - &p->cpus_allowed) && cpumask_and(later_mask, - later_mask, cpu_active_mask)) { + if (later_mask && cpumask_and(later_mask, later_mask, cp->free_cpus)) { best_cpu = cpumask_any(later_mask); goto out; } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) && diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index efb94124420d..abfaf3d9a29f 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1164,6 +1164,13 @@ static int find_later_rq(struct task_struct *task) if (task->nr_cpus_allowed == 1) return -1; + /* + * We have to consider system topology and task affinity + * first, then we can look for a suitable cpu. + */ + cpumask_copy(later_mask, task_rq(task)->rd->span); + cpumask_and(later_mask, later_mask, cpu_active_mask); + cpumask_and(later_mask, later_mask, &task->cpus_allowed); best_cpu = cpudl_find(&task_rq(task)->rd->cpudl, task, later_mask); if (best_cpu == -1) |
