jump_label: Add atomic_t interface

Add an interface to allow usage of jump_labels with atomic counters.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101014203625.501657727@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2010-10-14 21:39:02 +02:00 committed by Ingo Molnar
parent 3b6e901f83
commit 8b92538d84
1 changed files with 44 additions and 0 deletions

View File

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#ifndef _LINUX_JUMP_LABEL_REF_H
#define _LINUX_JUMP_LABEL_REF_H
#include <linux/jump_label.h>
#include <asm/atomic.h>
#ifdef HAVE_JUMP_LABEL
static inline void jump_label_inc(atomic_t *key)
{
if (atomic_add_return(1, key) == 1)
jump_label_enable(key);
}
static inline void jump_label_dec(atomic_t *key)
{
if (atomic_dec_and_test(key))
jump_label_disable(key);
}
#else /* !HAVE_JUMP_LABEL */
static inline void jump_label_inc(atomic_t *key)
{
atomic_inc(key);
}
static inline void jump_label_dec(atomic_t *key)
{
atomic_dec(key);
}
#undef JUMP_LABEL
#define JUMP_LABEL(key, label) \
do { \
if (unlikely(__builtin_choose_expr( \
__builtin_types_compatible_p(typeof(key), atomic_t *), \
atomic_read((atomic_t *)(key)), *(key)))) \
goto label; \
} while (0)
#endif /* HAVE_JUMP_LABEL */
#endif /* _LINUX_JUMP_LABEL_REF_H */