Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[safe/jmp/linux-2.6] / include / linux / percpu_counter.h

diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index 6825255..a7684a5 100644 (file)
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -6,42 +6,58 @@
  * WARNING: these things are HUGE.  4 kbytes per counter on 32-way P4.
  */
 
-#include <linux/config.h>
 #include <linux/spinlock.h>
 #include <linux/smp.h>
+#include <linux/list.h>
 #include <linux/threads.h>
 #include <linux/percpu.h>
+#include <linux/types.h>
 
 #ifdef CONFIG_SMP
 
 struct percpu_counter {
        spinlock_t lock;
-       long count;
-       long *counters;
+       s64 count;
+#ifdef CONFIG_HOTPLUG_CPU
+       struct list_head list;  /* All percpu_counters are on a list */
+#endif
+       s32 *counters;
 };
 
-#if NR_CPUS >= 16
-#define FBC_BATCH      (NR_CPUS*2)
-#else
-#define FBC_BATCH      (NR_CPUS*4)
-#endif
+extern int percpu_counter_batch;
+
+int __percpu_counter_init(struct percpu_counter *fbc, s64 amount,
+                         struct lock_class_key *key);
+
+#define percpu_counter_init(fbc, value)                                        \
+       ({                                                              \
+               static struct lock_class_key __key;                     \
+                                                                       \
+               __percpu_counter_init(fbc, value, &__key);              \
+       })
 
-static inline void percpu_counter_init(struct percpu_counter *fbc)
+void percpu_counter_destroy(struct percpu_counter *fbc);
+void percpu_counter_set(struct percpu_counter *fbc, s64 amount);
+void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch);
+s64 __percpu_counter_sum(struct percpu_counter *fbc);
+
+static inline void percpu_counter_add(struct percpu_counter *fbc, s64 amount)
 {
-       spin_lock_init(&fbc->lock);
-       fbc->count = 0;
-       fbc->counters = alloc_percpu(long);
+       __percpu_counter_add(fbc, amount, percpu_counter_batch);
 }
 
-static inline void percpu_counter_destroy(struct percpu_counter *fbc)
+static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
 {
-       free_percpu(fbc->counters);
+       s64 ret = __percpu_counter_sum(fbc);
+       return ret < 0 ? 0 : ret;
 }
 
-void percpu_counter_mod(struct percpu_counter *fbc, long amount);
-long percpu_counter_sum(struct percpu_counter *fbc);
+static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
+{
+       return __percpu_counter_sum(fbc);
+}
 
-static inline long percpu_counter_read(struct percpu_counter *fbc)
+static inline s64 percpu_counter_read(struct percpu_counter *fbc)
 {
        return fbc->count;
 }
@@ -49,13 +65,14 @@ static inline long percpu_counter_read(struct percpu_counter *fbc)
 /*
  * It is possible for the percpu_counter_read() to return a small negative
  * number for some counter which should never be negative.
+ *
  */
-static inline long percpu_counter_read_positive(struct percpu_counter *fbc)
+static inline s64 percpu_counter_read_positive(struct percpu_counter *fbc)
 {
-       long ret = fbc->count;
+       s64 ret = fbc->count;
 
        barrier();              /* Prevent reloads of fbc->count */
-       if (ret > 0)
+       if (ret >= 0)
                return ret;
        return 1;
 }
@@ -63,51 +80,70 @@ static inline long percpu_counter_read_positive(struct percpu_counter *fbc)
 #else
 
 struct percpu_counter {
-       long count;
+       s64 count;
 };
 
-static inline void percpu_counter_init(struct percpu_counter *fbc)
+static inline int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
 {
-       fbc->count = 0;
+       fbc->count = amount;
+       return 0;
 }
 
 static inline void percpu_counter_destroy(struct percpu_counter *fbc)
 {
 }
 
+static inline void percpu_counter_set(struct percpu_counter *fbc, s64 amount)
+{
+       fbc->count = amount;
+}
+
+#define __percpu_counter_add(fbc, amount, batch) \
+       percpu_counter_add(fbc, amount)
+
 static inline void
-percpu_counter_mod(struct percpu_counter *fbc, long amount)
+percpu_counter_add(struct percpu_counter *fbc, s64 amount)
 {
        preempt_disable();
        fbc->count += amount;
        preempt_enable();
 }
 
-static inline long percpu_counter_read(struct percpu_counter *fbc)
+static inline s64 percpu_counter_read(struct percpu_counter *fbc)
 {
        return fbc->count;
 }
 
-static inline long percpu_counter_read_positive(struct percpu_counter *fbc)
+static inline s64 percpu_counter_read_positive(struct percpu_counter *fbc)
 {
        return fbc->count;
 }
 
-static inline long percpu_counter_sum(struct percpu_counter *fbc)
+static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
 {
        return percpu_counter_read_positive(fbc);
 }
 
+static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
+{
+       return percpu_counter_read(fbc);
+}
+
 #endif /* CONFIG_SMP */
 
 static inline void percpu_counter_inc(struct percpu_counter *fbc)
 {
-       percpu_counter_mod(fbc, 1);
+       percpu_counter_add(fbc, 1);
 }
 
 static inline void percpu_counter_dec(struct percpu_counter *fbc)
 {
-       percpu_counter_mod(fbc, -1);
+       percpu_counter_add(fbc, -1);
+}
+
+static inline void percpu_counter_sub(struct percpu_counter *fbc, s64 amount)
+{
+       percpu_counter_add(fbc, -amount);
 }
 
 #endif /* _LINUX_PERCPU_COUNTER_H */