+++ /dev/null
-#ifndef __LINUX_SEQLOCK_H
-#define __LINUX_SEQLOCK_H
-
-#include <linux/compiler.h>
-
-typedef struct seqcount {
- unsigned sequence;
-} seqcount_t;
-
-static inline void seqcount_init(seqcount_t *s)
-{
- s->sequence = 0;
-}
-
-static inline unsigned read_seqcount_begin(const seqcount_t *s)
-{
- unsigned ret;
-
-repeat:
- ret = READ_ONCE(s->sequence);
- if (unlikely(ret & 1)) {
- cpu_relax();
- goto repeat;
- }
- smp_rmb();
- return ret;
-}
-
-static inline int read_seqcount_retry(const seqcount_t *s, unsigned start)
-{
- smp_rmb();
- return unlikely(s->sequence != start);
-}
-
-static inline void write_seqcount_begin(seqcount_t *s)
-{
- s->sequence++;
- smp_wmb();
-}
-
-static inline void write_seqcount_end(seqcount_t *s)
-{
- smp_wmb();
- s->sequence++;
-}
-
-#endif /* __LINUX_SEQLOCK_H */