diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/rcu/tree.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 156ac8d0418b..e299cd0ddd97 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2824,6 +2824,8 @@ struct kfree_rcu_cpu { struct delayed_work monitor_work; bool monitor_todo; bool initialized; + // Number of objects for which GP not started + int count; }; static DEFINE_PER_CPU(struct kfree_rcu_cpu, krc); @@ -2937,6 +2939,8 @@ static inline bool queue_kfree_rcu_work(struct kfree_rcu_cpu *krcp) krcp->head = NULL; } + krcp->count = 0; + /* * One work is per one batch, so there are two "free channels", * "bhead_free" and "head_free" the batch can handle. It can be @@ -3073,6 +3077,8 @@ void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func) krcp->head = head; } + krcp->count++; + // Set timer to drain after KFREE_DRAIN_JIFFIES. if (rcu_scheduler_active == RCU_SCHEDULER_RUNNING && !krcp->monitor_todo) { @@ -3087,6 +3093,58 @@ unlock_return: } EXPORT_SYMBOL_GPL(kfree_call_rcu); +static unsigned long +kfree_rcu_shrink_count(struct shrinker *shrink, struct shrink_control *sc) +{ + int cpu; + unsigned long flags, count = 0; + + /* Snapshot count of all CPUs */ + for_each_online_cpu(cpu) { + struct kfree_rcu_cpu *krcp = per_cpu_ptr(&krc, cpu); + + spin_lock_irqsave(&krcp->lock, flags); + count += krcp->count; + spin_unlock_irqrestore(&krcp->lock, flags); + } + + return count; +} + +static unsigned long +kfree_rcu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + int cpu, freed = 0; + unsigned long flags; + + for_each_online_cpu(cpu) { + int count; + struct kfree_rcu_cpu *krcp = per_cpu_ptr(&krc, cpu); + + count = krcp->count; + spin_lock_irqsave(&krcp->lock, flags); + if (krcp->monitor_todo) + kfree_rcu_drain_unlock(krcp, flags); + else + spin_unlock_irqrestore(&krcp->lock, flags); + + sc->nr_to_scan -= count; + freed += count; + + if (sc->nr_to_scan <= 0) + break; + } + + return freed; +} + +static struct shrinker kfree_rcu_shrinker = { + .count_objects = kfree_rcu_shrink_count, + .scan_objects = kfree_rcu_shrink_scan, + .batch = 0, + .seeks = DEFAULT_SEEKS, +}; + void __init kfree_rcu_scheduler_running(void) { int cpu; @@ -4007,6 +4065,8 @@ static void __init kfree_rcu_batch_init(void) INIT_DELAYED_WORK(&krcp->monitor_work, kfree_rcu_monitor); krcp->initialized = true; } + if (register_shrinker(&kfree_rcu_shrinker)) + pr_err("Failed to register kfree_rcu() shrinker!\n"); } void __init rcu_init(void) |