IB/ipath: iba6110 rev4 no longer needs recv header overrun workaround

[linux-2.6-omap-h63xx.git] / lib / percpu_counter.c

diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c
index 850449080e1cfb7f619eca4ae5d5ed6aca01a1d0..cf22c617baa44db8708f9908efc64b9f767e0c92 100644 (file)
--- a/lib/percpu_counter.c
+++ b/lib/percpu_counter.c
@@ -3,8 +3,17 @@
  */
 
 #include <linux/percpu_counter.h>
+#include <linux/notifier.h>
+#include <linux/mutex.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
 #include <linux/module.h>
 
+#ifdef CONFIG_HOTPLUG_CPU
+static LIST_HEAD(percpu_counters);
+static DEFINE_MUTEX(percpu_counters_lock);
+#endif
+
 void percpu_counter_mod(struct percpu_counter *fbc, s32 amount)
 {
        long count;
@@ -36,7 +45,7 @@ s64 percpu_counter_sum(struct percpu_counter *fbc)
 
        spin_lock(&fbc->lock);
        ret = fbc->count;
-       for_each_possible_cpu(cpu) {
+       for_each_online_cpu(cpu) {
                s32 *pcount = per_cpu_ptr(fbc->counters, cpu);
                ret += *pcount;
        }
@@ -44,3 +53,60 @@ s64 percpu_counter_sum(struct percpu_counter *fbc)
        return ret < 0 ? 0 : ret;
 }
 EXPORT_SYMBOL(percpu_counter_sum);
+
+void percpu_counter_init(struct percpu_counter *fbc, s64 amount)
+{
+       spin_lock_init(&fbc->lock);
+       fbc->count = amount;
+       fbc->counters = alloc_percpu(s32);
+#ifdef CONFIG_HOTPLUG_CPU
+       mutex_lock(&percpu_counters_lock);
+       list_add(&fbc->list, &percpu_counters);
+       mutex_unlock(&percpu_counters_lock);
+#endif
+}
+EXPORT_SYMBOL(percpu_counter_init);
+
+void percpu_counter_destroy(struct percpu_counter *fbc)
+{
+       free_percpu(fbc->counters);
+#ifdef CONFIG_HOTPLUG_CPU
+       mutex_lock(&percpu_counters_lock);
+       list_del(&fbc->list);
+       mutex_unlock(&percpu_counters_lock);
+#endif
+}
+EXPORT_SYMBOL(percpu_counter_destroy);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int __cpuinit percpu_counter_hotcpu_callback(struct notifier_block *nb,
+                                       unsigned long action, void *hcpu)
+{
+       unsigned int cpu;
+       struct percpu_counter *fbc;
+
+       if (action != CPU_DEAD)
+               return NOTIFY_OK;
+
+       cpu = (unsigned long)hcpu;
+       mutex_lock(&percpu_counters_lock);
+       list_for_each_entry(fbc, &percpu_counters, list) {
+               s32 *pcount;
+
+               spin_lock(&fbc->lock);
+               pcount = per_cpu_ptr(fbc->counters, cpu);
+               fbc->count += *pcount;
+               *pcount = 0;
+               spin_unlock(&fbc->lock);
+       }
+       mutex_unlock(&percpu_counters_lock);
+       return NOTIFY_OK;
+}
+
+static int __init percpu_counter_startup(void)
+{
+       hotcpu_notifier(percpu_counter_hotcpu_callback, 0);
+       return 0;
+}
+module_init(percpu_counter_startup);
+#endif