pcpcntr: add group allocation/free

[linux-2.6-block.git] / lib / percpu_counter.c

diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index 5004463c4f9f1243674ca77c2aea8e7050edfbda..9073430dc8659c7e37aa262874b991c3677d6b06 100644 (file)
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -151,48 +151,72 @@ s64 __percpu_counter_sum(struct percpu_counter *fbc)
 }
 EXPORT_SYMBOL(__percpu_counter_sum);
 
-int __percpu_counter_init(struct percpu_counter *fbc, s64 amount, gfp_t gfp,
-                         struct lock_class_key *key)
+int __percpu_counter_init_many(struct percpu_counter *fbc, s64 amount,
+                              gfp_t gfp, u32 nr_counters,
+                              struct lock_class_key *key)
 {
        unsigned long flags __maybe_unused;
-
-       raw_spin_lock_init(&fbc->lock);
-       lockdep_set_class(&fbc->lock, key);
-       fbc->count = amount;
-       fbc->counters = alloc_percpu_gfp(s32, gfp);
-       if (!fbc->counters)
+       size_t counter_size;
+       s32 __percpu *counters;
+       u32 i;
+
+       counter_size = ALIGN(sizeof(*counters), __alignof__(*counters));
+       counters = __alloc_percpu_gfp(nr_counters * counter_size,
+                                     __alignof__(*counters), gfp);
+       if (!counters) {
+               fbc[0].counters = NULL;
                return -ENOMEM;
+       }
 
-       debug_percpu_counter_activate(fbc);
+       for (i = 0; i < nr_counters; i++) {
+               raw_spin_lock_init(&fbc[i].lock);
+               lockdep_set_class(&fbc[i].lock, key);
+#ifdef CONFIG_HOTPLUG_CPU
+               INIT_LIST_HEAD(&fbc[i].list);
+#endif
+               fbc[i].count = amount;
+               fbc[i].counters = (void *)counters + (i * counter_size);
+
+               debug_percpu_counter_activate(&fbc[i]);
+       }
 
 #ifdef CONFIG_HOTPLUG_CPU
-       INIT_LIST_HEAD(&fbc->list);
        spin_lock_irqsave(&percpu_counters_lock, flags);
-       list_add(&fbc->list, &percpu_counters);
+       for (i = 0; i < nr_counters; i++)
+               list_add(&fbc[i].list, &percpu_counters);
        spin_unlock_irqrestore(&percpu_counters_lock, flags);
 #endif
        return 0;
 }
-EXPORT_SYMBOL(__percpu_counter_init);
+EXPORT_SYMBOL(__percpu_counter_init_many);
 
-void percpu_counter_destroy(struct percpu_counter *fbc)
+void percpu_counter_destroy_many(struct percpu_counter *fbc, u32 nr_counters)
 {
        unsigned long flags __maybe_unused;
+       u32 i;
+
+       if (WARN_ON_ONCE(!fbc))
+               return;
 
-       if (!fbc->counters)
+       if (!fbc[0].counters)
                return;
 
-       debug_percpu_counter_deactivate(fbc);
+       for (i = 0; i < nr_counters; i++)
+               debug_percpu_counter_deactivate(&fbc[i]);
 
 #ifdef CONFIG_HOTPLUG_CPU
        spin_lock_irqsave(&percpu_counters_lock, flags);
-       list_del(&fbc->list);
+       for (i = 0; i < nr_counters; i++)
+               list_del(&fbc[i].list);
        spin_unlock_irqrestore(&percpu_counters_lock, flags);
 #endif
-       free_percpu(fbc->counters);
-       fbc->counters = NULL;
+
+       free_percpu(fbc[0].counters);
+
+       for (i = 0; i < nr_counters; i++)
+               fbc[i].counters = NULL;
 }
-EXPORT_SYMBOL(percpu_counter_destroy);
+EXPORT_SYMBOL(percpu_counter_destroy_many);
 
 int percpu_counter_batch __read_mostly = 32;
 EXPORT_SYMBOL(percpu_counter_batch);