mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: fix rcutorture bug rcu: eliminate synchronize_rcu_xxx macro rcu: make treercu safe for suspend and resume rcu: fix rcutree grace-period-latency bug on small systems futex: catch certain assymetric (get|put)_futex_key calls futex: make futex_(get|put)_key() calls symmetric locking, percpu counters: introduce separate lock classes swiotlb: clean up EXPORT_SYMBOL usage swiotlb: remove unnecessary declaration swiotlb: replace architecture-specific swiotlb.h with linux/swiotlb.h swiotlb: add support for systems with highmem swiotlb: store phys address in io_tlb_orig_addr array swiotlb: add hwdev to swiotlb_phys_to_bus() / swiotlb_sg_to_bus()
149 lines
3.2 KiB
C
149 lines
3.2 KiB
C
#ifndef _LINUX_PERCPU_COUNTER_H
|
|
#define _LINUX_PERCPU_COUNTER_H
|
|
/*
|
|
* A simple "approximate counter" for use in ext2 and ext3 superblocks.
|
|
*
|
|
* WARNING: these things are HUGE. 4 kbytes per counter on 32-way P4.
|
|
*/
|
|
|
|
#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;
|
|
s64 count;
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
struct list_head list; /* All percpu_counters are on a list */
|
|
#endif
|
|
s32 *counters;
|
|
};
|
|
|
|
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); \
|
|
})
|
|
|
|
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)
|
|
{
|
|
__percpu_counter_add(fbc, amount, percpu_counter_batch);
|
|
}
|
|
|
|
static inline s64 percpu_counter_sum_positive(struct percpu_counter *fbc)
|
|
{
|
|
s64 ret = __percpu_counter_sum(fbc);
|
|
return ret < 0 ? 0 : ret;
|
|
}
|
|
|
|
static inline s64 percpu_counter_sum(struct percpu_counter *fbc)
|
|
{
|
|
return __percpu_counter_sum(fbc);
|
|
}
|
|
|
|
static inline s64 percpu_counter_read(struct percpu_counter *fbc)
|
|
{
|
|
return fbc->count;
|
|
}
|
|
|
|
/*
|
|
* It is possible for the percpu_counter_read() to return a small negative
|
|
* number for some counter which should never be negative.
|
|
*
|
|
*/
|
|
static inline s64 percpu_counter_read_positive(struct percpu_counter *fbc)
|
|
{
|
|
s64 ret = fbc->count;
|
|
|
|
barrier(); /* Prevent reloads of fbc->count */
|
|
if (ret >= 0)
|
|
return ret;
|
|
return 1;
|
|
}
|
|
|
|
#else
|
|
|
|
struct percpu_counter {
|
|
s64 count;
|
|
};
|
|
|
|
static inline int percpu_counter_init(struct percpu_counter *fbc, s64 amount)
|
|
{
|
|
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_add(struct percpu_counter *fbc, s64 amount)
|
|
{
|
|
preempt_disable();
|
|
fbc->count += amount;
|
|
preempt_enable();
|
|
}
|
|
|
|
static inline s64 percpu_counter_read(struct percpu_counter *fbc)
|
|
{
|
|
return fbc->count;
|
|
}
|
|
|
|
static inline s64 percpu_counter_read_positive(struct percpu_counter *fbc)
|
|
{
|
|
return fbc->count;
|
|
}
|
|
|
|
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_add(fbc, 1);
|
|
}
|
|
|
|
static inline void percpu_counter_dec(struct percpu_counter *fbc)
|
|
{
|
|
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 */
|