percpu_counter: new function percpu_counter_sum_and_set

[linux-2.6-omap-h63xx.git] / include / linux / percpu_counter.h

diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index 66b5de404f22fa1c9af9e5224e879bdb6b3f290e..20838883535704c89cf72bafe29a28d12dea45e3 100644 (file)
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -8,15 +8,20 @@
 
 #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
@@ -25,22 +30,36 @@ struct percpu_counter {
 #define FBC_BATCH      (NR_CPUS*4)
 #endif
 
-static inline void percpu_counter_init(struct percpu_counter *fbc)
+int percpu_counter_init(struct percpu_counter *fbc, s64 amount);
+int percpu_counter_init_irq(struct percpu_counter *fbc, s64 amount);
+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, int set);
+
+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, FBC_BATCH);
 }
 
-static inline void percpu_counter_destroy(struct percpu_counter *fbc)
+static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
+{
+       s64 ret = __percpu_counter_sum(fbc, 0);
+       return ret < 0 ? 0 : ret;
+}
+
+static inline s64 percpu_counter_sum_and_set(struct percpu_counter *fbc)
 {
-       free_percpu(fbc->counters);
+       return __percpu_counter_sum(fbc, 1);
 }
 
-void percpu_counter_mod(struct percpu_counter *fbc, long amount);
-long percpu_counter_sum(struct percpu_counter *fbc);
 
-static inline long percpu_counter_read(struct percpu_counter *fbc)
+static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
+{
+       return __percpu_counter_sum(fbc, 0);
+}
+
+static inline s64 percpu_counter_read(struct percpu_counter *fbc)
 {
        return fbc->count;
 }
@@ -48,13 +67,14 @@ 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;
 }
@@ -62,51 +82,72 @@ 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;
 }
 
+#define percpu_counter_init_irq percpu_counter_init
+
 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 */