diff options
Diffstat (limited to 'include/linux/seqlock.h')
| -rw-r--r-- | include/linux/seqlock.h | 52 |
1 files changed, 31 insertions, 21 deletions
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index e9bd2f65d7f4..e92f9d5577ba 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -191,11 +191,9 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s) * @lockname: "LOCKNAME" part of seqcount_LOCKNAME_t * @locktype: LOCKNAME canonical C data type * @preemptible: preemptibility of above locktype - * @lockmember: argument for lockdep_assert_held() - * @lockbase: associated lock release function (prefix only) - * @lock_acquire: associated lock acquisition function (full call) + * @lockbase: prefix for associated lock/unlock */ -#define SEQCOUNT_LOCKNAME(lockname, locktype, preemptible, lockmember, lockbase, lock_acquire) \ +#define SEQCOUNT_LOCKNAME(lockname, locktype, preemptible, lockbase) \ typedef struct seqcount_##lockname { \ seqcount_t seqcount; \ __SEQ_LOCK(locktype *lock); \ @@ -207,6 +205,12 @@ __seqprop_##lockname##_ptr(seqcount_##lockname##_t *s) \ return &s->seqcount; \ } \ \ +static __always_inline const seqcount_t * \ +__seqprop_##lockname##_const_ptr(const seqcount_##lockname##_t *s) \ +{ \ + return &s->seqcount; \ +} \ + \ static __always_inline unsigned \ __seqprop_##lockname##_sequence(const seqcount_##lockname##_t *s) \ { \ @@ -216,7 +220,7 @@ __seqprop_##lockname##_sequence(const seqcount_##lockname##_t *s) \ return seq; \ \ if (preemptible && unlikely(seq & 1)) { \ - __SEQ_LOCK(lock_acquire); \ + __SEQ_LOCK(lockbase##_lock(s->lock)); \ __SEQ_LOCK(lockbase##_unlock(s->lock)); \ \ /* \ @@ -242,7 +246,7 @@ __seqprop_##lockname##_preemptible(const seqcount_##lockname##_t *s) \ static __always_inline void \ __seqprop_##lockname##_assert(const seqcount_##lockname##_t *s) \ { \ - __SEQ_LOCK(lockdep_assert_held(lockmember)); \ + __SEQ_LOCK(lockdep_assert_held(s->lock)); \ } /* @@ -254,6 +258,11 @@ static inline seqcount_t *__seqprop_ptr(seqcount_t *s) return s; } +static inline const seqcount_t *__seqprop_const_ptr(const seqcount_t *s) +{ + return s; +} + static inline unsigned __seqprop_sequence(const seqcount_t *s) { return READ_ONCE(s->sequence); @@ -271,10 +280,10 @@ static inline void __seqprop_assert(const seqcount_t *s) #define __SEQ_RT IS_ENABLED(CONFIG_PREEMPT_RT) -SEQCOUNT_LOCKNAME(raw_spinlock, raw_spinlock_t, false, s->lock, raw_spin, raw_spin_lock(s->lock)) -SEQCOUNT_LOCKNAME(spinlock, spinlock_t, __SEQ_RT, s->lock, spin, spin_lock(s->lock)) -SEQCOUNT_LOCKNAME(rwlock, rwlock_t, __SEQ_RT, s->lock, read, read_lock(s->lock)) -SEQCOUNT_LOCKNAME(mutex, struct mutex, true, s->lock, mutex, mutex_lock(s->lock)) +SEQCOUNT_LOCKNAME(raw_spinlock, raw_spinlock_t, false, raw_spin) +SEQCOUNT_LOCKNAME(spinlock, spinlock_t, __SEQ_RT, spin) +SEQCOUNT_LOCKNAME(rwlock, rwlock_t, __SEQ_RT, read) +SEQCOUNT_LOCKNAME(mutex, struct mutex, true, mutex) /* * SEQCNT_LOCKNAME_ZERO - static initializer for seqcount_LOCKNAME_t @@ -294,19 +303,20 @@ SEQCOUNT_LOCKNAME(mutex, struct mutex, true, s->lock, mutex #define SEQCNT_WW_MUTEX_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock) #define __seqprop_case(s, lockname, prop) \ - seqcount_##lockname##_t: __seqprop_##lockname##_##prop((void *)(s)) + seqcount_##lockname##_t: __seqprop_##lockname##_##prop #define __seqprop(s, prop) _Generic(*(s), \ - seqcount_t: __seqprop_##prop((void *)(s)), \ + seqcount_t: __seqprop_##prop, \ __seqprop_case((s), raw_spinlock, prop), \ __seqprop_case((s), spinlock, prop), \ __seqprop_case((s), rwlock, prop), \ __seqprop_case((s), mutex, prop)) -#define seqprop_ptr(s) __seqprop(s, ptr) -#define seqprop_sequence(s) __seqprop(s, sequence) -#define seqprop_preemptible(s) __seqprop(s, preemptible) -#define seqprop_assert(s) __seqprop(s, assert) +#define seqprop_ptr(s) __seqprop(s, ptr)(s) +#define seqprop_const_ptr(s) __seqprop(s, const_ptr)(s) +#define seqprop_sequence(s) __seqprop(s, sequence)(s) +#define seqprop_preemptible(s) __seqprop(s, preemptible)(s) +#define seqprop_assert(s) __seqprop(s, assert)(s) /** * __read_seqcount_begin() - begin a seqcount_t read section w/o barrier @@ -355,7 +365,7 @@ SEQCOUNT_LOCKNAME(mutex, struct mutex, true, s->lock, mutex */ #define read_seqcount_begin(s) \ ({ \ - seqcount_lockdep_reader_access(seqprop_ptr(s)); \ + seqcount_lockdep_reader_access(seqprop_const_ptr(s)); \ raw_read_seqcount_begin(s); \ }) @@ -421,7 +431,7 @@ SEQCOUNT_LOCKNAME(mutex, struct mutex, true, s->lock, mutex * Return: true if a read section retry is required, else false */ #define __read_seqcount_retry(s, start) \ - do___read_seqcount_retry(seqprop_ptr(s), start) + do___read_seqcount_retry(seqprop_const_ptr(s), start) static inline int do___read_seqcount_retry(const seqcount_t *s, unsigned start) { @@ -441,7 +451,7 @@ static inline int do___read_seqcount_retry(const seqcount_t *s, unsigned start) * Return: true if a read section retry is required, else false */ #define read_seqcount_retry(s, start) \ - do_read_seqcount_retry(seqprop_ptr(s), start) + do_read_seqcount_retry(seqprop_const_ptr(s), start) static inline int do_read_seqcount_retry(const seqcount_t *s, unsigned start) { @@ -574,7 +584,7 @@ static inline void do_write_seqcount_end(seqcount_t *s) * via WRITE_ONCE): a) to ensure the writes become visible to other threads * atomically, avoiding compiler optimizations; b) to document which writes are * meant to propagate to the reader critical section. This is necessary because - * neither writes before and after the barrier are enclosed in a seq-writer + * neither writes before nor after the barrier are enclosed in a seq-writer * critical section that would ensure readers are aware of ongoing writes:: * * seqcount_t seq; @@ -864,7 +874,7 @@ static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start) } /* - * For all seqlock_t write side functions, use the the internal + * For all seqlock_t write side functions, use the internal * do_write_seqcount_begin() instead of generic write_seqcount_begin(). * This way, no redundant lockdep_assert_held() checks are added. */ |