diff options
| author | Linux Build Service Account <lnxbuild@localhost> | 2016-11-10 22:49:39 -0800 |
|---|---|---|
| committer | Gerrit - the friendly Code Review server <code-review@localhost> | 2016-11-10 22:49:39 -0800 |
| commit | 2401d64a48302bad3fc74e8ca02edd188d27ae61 (patch) | |
| tree | 21d21cfc4a4401e4a2e0eb0388f7d20f9bfd25c4 | |
| parent | 896ddc1b329090ec02a777a5d59be8dedd3543a3 (diff) | |
| parent | c82e2f73d1028cd1ff2d6b767ea656909888e516 (diff) | |
Merge "core_ctl: Synchronize access to cluster cpu list"
| -rw-r--r-- | kernel/sched/core_ctl.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/kernel/sched/core_ctl.c b/kernel/sched/core_ctl.c index 0db85a4fa9c8..ecf6c568f0b5 100644 --- a/kernel/sched/core_ctl.c +++ b/kernel/sched/core_ctl.c @@ -719,8 +719,18 @@ static void move_cpu_lru(struct cpu_data *cpu_data) static void try_to_isolate(struct cluster_data *cluster, unsigned int need) { struct cpu_data *c, *tmp; + unsigned long flags; + unsigned int num_cpus = cluster->num_cpus; + /* + * Protect against entry being removed (and added at tail) by other + * thread (hotplug). + */ + spin_lock_irqsave(&state_lock, flags); list_for_each_entry_safe(c, tmp, &cluster->lru, sib) { + if (!num_cpus--) + break; + if (!is_active(c)) continue; if (cluster->active_cpus == need) @@ -729,6 +739,8 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need) if (c->is_busy) continue; + spin_unlock_irqrestore(&state_lock, flags); + pr_debug("Trying to isolate CPU%u\n", c->cpu); if (!sched_isolate_cpu(c->cpu)) { c->isolated_by_us = true; @@ -738,7 +750,9 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need) pr_debug("Unable to isolate CPU%u\n", c->cpu); } cluster->active_cpus = get_active_cpu_count(cluster); + spin_lock_irqsave(&state_lock, flags); } + spin_unlock_irqrestore(&state_lock, flags); /* * If the number of active CPUs is within the limits, then @@ -747,12 +761,19 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need) if (cluster->active_cpus <= cluster->max_cpus) return; + num_cpus = cluster->num_cpus; + spin_lock_irqsave(&state_lock, flags); list_for_each_entry_safe(c, tmp, &cluster->lru, sib) { + if (!num_cpus--) + break; + if (!is_active(c)) continue; if (cluster->active_cpus <= cluster->max_cpus) break; + spin_unlock_irqrestore(&state_lock, flags); + pr_debug("Trying to isolate CPU%u\n", c->cpu); if (!sched_isolate_cpu(c->cpu)) { c->isolated_by_us = true; @@ -762,15 +783,28 @@ static void try_to_isolate(struct cluster_data *cluster, unsigned int need) pr_debug("Unable to isolate CPU%u\n", c->cpu); } cluster->active_cpus = get_active_cpu_count(cluster); + spin_lock_irqsave(&state_lock, flags); } + spin_unlock_irqrestore(&state_lock, flags); + } static void __try_to_unisolate(struct cluster_data *cluster, unsigned int need, bool force) { struct cpu_data *c, *tmp; + unsigned long flags; + unsigned int num_cpus = cluster->num_cpus; + /* + * Protect against entry being removed (and added at tail) by other + * thread (hotplug). + */ + spin_lock_irqsave(&state_lock, flags); list_for_each_entry_safe(c, tmp, &cluster->lru, sib) { + if (!num_cpus--) + break; + if (!c->isolated_by_us) continue; if ((c->online && !cpu_isolated(c->cpu)) || @@ -779,6 +813,8 @@ static void __try_to_unisolate(struct cluster_data *cluster, if (cluster->active_cpus == need) break; + spin_unlock_irqrestore(&state_lock, flags); + pr_debug("Trying to unisolate CPU%u\n", c->cpu); if (!sched_unisolate_cpu(c->cpu)) { c->isolated_by_us = false; @@ -787,7 +823,9 @@ static void __try_to_unisolate(struct cluster_data *cluster, pr_debug("Unable to unisolate CPU%u\n", c->cpu); } cluster->active_cpus = get_active_cpu_count(cluster); + spin_lock_irqsave(&state_lock, flags); } + spin_unlock_irqrestore(&state_lock, flags); } static void try_to_unisolate(struct cluster_data *cluster, unsigned int need) |