diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/percpu_counter.c | 15 | ||||
| -rw-r--r-- | lib/percpu_ida.c | 89 |
2 files changed, 81 insertions, 23 deletions
diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c index 93c5d5e..7473ee3 100644 --- a/lib/percpu_counter.c +++ b/lib/percpu_counter.c @@ -60,14 +60,15 @@ static inline void debug_percpu_counter_deactivate(struct percpu_counter *fbc) void percpu_counter_set(struct percpu_counter *fbc, s64 amount) { int cpu; + unsigned long flags; - raw_spin_lock(&fbc->lock); + raw_spin_lock_irqsave(&fbc->lock, flags); for_each_possible_cpu(cpu) { s32 *pcount = per_cpu_ptr(fbc->counters, cpu); *pcount = 0; } fbc->count = amount; - raw_spin_unlock(&fbc->lock); + raw_spin_unlock_irqrestore(&fbc->lock, flags); } EXPORT_SYMBOL(percpu_counter_set); @@ -78,9 +79,10 @@ void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch) preempt_disable(); count = __this_cpu_read(*fbc->counters) + amount; if (count >= batch || count <= -batch) { - raw_spin_lock(&fbc->lock); + unsigned long flags; + raw_spin_lock_irqsave(&fbc->lock, flags); fbc->count += count; - raw_spin_unlock(&fbc->lock); + raw_spin_unlock_irqrestore(&fbc->lock, flags); __this_cpu_write(*fbc->counters, 0); } else { __this_cpu_write(*fbc->counters, count); @@ -97,14 +99,15 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc) { s64 ret; int cpu; + unsigned long flags; - raw_spin_lock(&fbc->lock); + raw_spin_lock_irqsave(&fbc->lock, flags); ret = fbc->count; for_each_online_cpu(cpu) { s32 *pcount = per_cpu_ptr(fbc->counters, cpu); ret += *pcount; } - raw_spin_unlock(&fbc->lock); + raw_spin_unlock_irqrestore(&fbc->lock, flags); return ret; } EXPORT_SYMBOL(__percpu_counter_sum); diff --git a/lib/percpu_ida.c b/lib/percpu_ida.c index bab1ba2..b0698ea 100644 --- a/lib/percpu_ida.c +++ b/lib/percpu_ida.c @@ -30,15 +30,6 @@ #include <linux/spinlock.h> #include <linux/percpu_ida.h> -/* - * Number of tags we move between the percpu freelist and the global freelist at - * a time - */ -#define IDA_PCPU_BATCH_MOVE 32U - -/* Max size of percpu freelist, */ -#define IDA_PCPU_SIZE ((IDA_PCPU_BATCH_MOVE * 3) / 2) - struct percpu_ida_cpu { /* * Even though this is percpu, we need a lock for tag stealing by remote @@ -78,7 +69,7 @@ static inline void steal_tags(struct percpu_ida *pool, struct percpu_ida_cpu *remote; for (cpus_have_tags = cpumask_weight(&pool->cpus_have_tags); - cpus_have_tags * IDA_PCPU_SIZE > pool->nr_tags / 2; + cpus_have_tags * pool->percpu_max_size > pool->nr_tags / 2; cpus_have_tags--) { cpu = cpumask_next(cpu, &pool->cpus_have_tags); @@ -123,7 +114,7 @@ static inline void alloc_global_tags(struct percpu_ida *pool, { move_tags(tags->freelist, &tags->nr_free, pool->freelist, &pool->nr_free, - min(pool->nr_free, IDA_PCPU_BATCH_MOVE)); + min(pool->nr_free, pool->percpu_batch_size)); } static inline unsigned alloc_local_tag(struct percpu_ida *pool, @@ -245,17 +236,17 @@ void percpu_ida_free(struct percpu_ida *pool, unsigned tag) wake_up(&pool->wait); } - if (nr_free == IDA_PCPU_SIZE) { + if (nr_free == pool->percpu_max_size) { spin_lock(&pool->lock); /* * Global lock held and irqs disabled, don't need percpu * lock */ - if (tags->nr_free == IDA_PCPU_SIZE) { + if (tags->nr_free == pool->percpu_max_size) { move_tags(pool->freelist, &pool->nr_free, tags->freelist, &tags->nr_free, - IDA_PCPU_BATCH_MOVE); + pool->percpu_batch_size); wake_up(&pool->wait); } @@ -292,7 +283,8 @@ EXPORT_SYMBOL_GPL(percpu_ida_destroy); * Allocation is percpu, but sharding is limited by nr_tags - for best * performance, the workload should not span more cpus than nr_tags / 128. */ -int percpu_ida_init(struct percpu_ida *pool, unsigned long nr_tags) +int __percpu_ida_init(struct percpu_ida *pool, unsigned long nr_tags, + unsigned long max_size, unsigned long batch_size) { unsigned i, cpu, order; @@ -301,6 +293,8 @@ int percpu_ida_init(struct percpu_ida *pool, unsigned long nr_tags) init_waitqueue_head(&pool->wait); spin_lock_init(&pool->lock); pool->nr_tags = nr_tags; + pool->percpu_max_size = max_size; + pool->percpu_batch_size = batch_size; /* Guard against overflow */ if (nr_tags > (unsigned) INT_MAX + 1) { @@ -319,7 +313,7 @@ int percpu_ida_init(struct percpu_ida *pool, unsigned long nr_tags) pool->nr_free = nr_tags; pool->tag_cpu = __alloc_percpu(sizeof(struct percpu_ida_cpu) + - IDA_PCPU_SIZE * sizeof(unsigned), + pool->percpu_max_size * sizeof(unsigned), sizeof(unsigned)); if (!pool->tag_cpu) goto err; @@ -332,4 +326,65 @@ err: percpu_ida_destroy(pool); return -ENOMEM; } -EXPORT_SYMBOL_GPL(percpu_ida_init); +EXPORT_SYMBOL_GPL(__percpu_ida_init); + +/** + * percpu_ida_for_each_free - iterate free ids of a pool + * @pool: pool to iterate + * @fn: interate callback function + * @data: parameter for @fn + * + * Note, this doesn't guarantee to iterate all free ids restrictly. Some free + * ids might be missed, some might be iterated duplicated, and some might + * be iterated and not free soon. + */ +int percpu_ida_for_each_free(struct percpu_ida *pool, percpu_ida_cb fn, + void *data) +{ + unsigned long flags; + struct percpu_ida_cpu *remote; + unsigned cpu, i, err = 0; + + local_irq_save(flags); + for_each_possible_cpu(cpu) { + remote = per_cpu_ptr(pool->tag_cpu, cpu); + spin_lock(&remote->lock); + for (i = 0; i < remote->nr_free; i++) { + err = fn(remote->freelist[i], data); + if (err) + break; + } + spin_unlock(&remote->lock); + if (err) + goto out; + } + + spin_lock(&pool->lock); + for (i = 0; i < pool->nr_free; i++) { + err = fn(pool->freelist[i], data); + if (err) + break; + } + spin_unlock(&pool->lock); +out: + local_irq_restore(flags); + return err; +} +EXPORT_SYMBOL_GPL(percpu_ida_for_each_free); + +/** + * percpu_ida_free_tags - return free tags number of a specific cpu or global pool + * @pool: pool related + * @cpu: specific cpu or global pool if @cpu == nr_cpu_ids + * + * Note: this just returns a snapshot of free tags number. + */ +unsigned percpu_ida_free_tags(struct percpu_ida *pool, int cpu) +{ + struct percpu_ida_cpu *remote; + if (cpu == nr_cpu_ids) + return pool->nr_free; + remote = per_cpu_ptr(pool->tag_cpu, cpu); + return remote->nr_free; +} +EXPORT_SYMBOL_GPL(percpu_ida_free_tags); |
