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seqlock: Fold seqcount_LOCKNAME_t definition
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Manual repetition is boring and error prone.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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Peter Zijlstra committed Jul 29, 2020
1 parent e55687f commit a8772dc
Showing 1 changed file with 39 additions and 103 deletions.
142 changes: 39 additions & 103 deletions include/linux/seqlock.h
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Original file line number Diff line number Diff line change
Expand Up @@ -149,21 +149,6 @@ do { \
__SEQ_LOCK((s)->lock = (assoc_lock)); \
} while (0)

/**
* typedef seqcount_spinlock_t - sequence counter with spinlock associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated spinlock
*
* A plain sequence counter with external writer synchronization by a
* spinlock. The spinlock is associated to the sequence count in the
* static initializer or init function. This enables lockdep to validate
* that the write side critical section is properly serialized.
*/
typedef struct seqcount_spinlock {
seqcount_t seqcount;
__SEQ_LOCK(spinlock_t *lock);
} seqcount_spinlock_t;

/**
* SEQCNT_SPINLOCK_ZERO - static initializer for seqcount_spinlock_t
* @name: Name of the seqcount_spinlock_t instance
Expand All @@ -180,21 +165,6 @@ typedef struct seqcount_spinlock {
#define seqcount_spinlock_init(s, lock) \
seqcount_locktype_init(s, lock)

/**
* typedef seqcount_raw_spinlock_t - sequence count with raw spinlock associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated raw spinlock
*
* A plain sequence counter with external writer synchronization by a
* raw spinlock. The raw spinlock is associated to the sequence count in
* the static initializer or init function. This enables lockdep to
* validate that the write side critical section is properly serialized.
*/
typedef struct seqcount_raw_spinlock {
seqcount_t seqcount;
__SEQ_LOCK(raw_spinlock_t *lock);
} seqcount_raw_spinlock_t;

/**
* SEQCNT_RAW_SPINLOCK_ZERO - static initializer for seqcount_raw_spinlock_t
* @name: Name of the seqcount_raw_spinlock_t instance
Expand All @@ -211,21 +181,6 @@ typedef struct seqcount_raw_spinlock {
#define seqcount_raw_spinlock_init(s, lock) \
seqcount_locktype_init(s, lock)

/**
* typedef seqcount_rwlock_t - sequence count with rwlock associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated rwlock
*
* A plain sequence counter with external writer synchronization by a
* rwlock. The rwlock is associated to the sequence count in the static
* initializer or init function. This enables lockdep to validate that
* the write side critical section is properly serialized.
*/
typedef struct seqcount_rwlock {
seqcount_t seqcount;
__SEQ_LOCK(rwlock_t *lock);
} seqcount_rwlock_t;

/**
* SEQCNT_RWLOCK_ZERO - static initializer for seqcount_rwlock_t
* @name: Name of the seqcount_rwlock_t instance
Expand All @@ -242,24 +197,6 @@ typedef struct seqcount_rwlock {
#define seqcount_rwlock_init(s, lock) \
seqcount_locktype_init(s, lock)

/**
* typedef seqcount_mutex_t - sequence count with mutex associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated mutex
*
* A plain sequence counter with external writer synchronization by a
* mutex. The mutex is associated to the sequence counter in the static
* initializer or init function. This enables lockdep to validate that
* the write side critical section is properly serialized.
*
* The write side API functions write_seqcount_begin()/end() automatically
* disable and enable preemption when used with seqcount_mutex_t.
*/
typedef struct seqcount_mutex {
seqcount_t seqcount;
__SEQ_LOCK(struct mutex *lock);
} seqcount_mutex_t;

/**
* SEQCNT_MUTEX_ZERO - static initializer for seqcount_mutex_t
* @name: Name of the seqcount_mutex_t instance
Expand All @@ -276,24 +213,6 @@ typedef struct seqcount_mutex {
#define seqcount_mutex_init(s, lock) \
seqcount_locktype_init(s, lock)

/**
* typedef seqcount_ww_mutex_t - sequence count with ww_mutex associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated ww_mutex
*
* A plain sequence counter with external writer synchronization by a
* ww_mutex. The ww_mutex is associated to the sequence counter in the static
* initializer or init function. This enables lockdep to validate that
* the write side critical section is properly serialized.
*
* The write side API functions write_seqcount_begin()/end() automatically
* disable and enable preemption when used with seqcount_ww_mutex_t.
*/
typedef struct seqcount_ww_mutex {
seqcount_t seqcount;
__SEQ_LOCK(struct ww_mutex *lock);
} seqcount_ww_mutex_t;

/**
* SEQCNT_WW_MUTEX_ZERO - static initializer for seqcount_ww_mutex_t
* @name: Name of the seqcount_ww_mutex_t instance
Expand All @@ -310,30 +229,50 @@ typedef struct seqcount_ww_mutex {
#define seqcount_ww_mutex_init(s, lock) \
seqcount_locktype_init(s, lock)

/*
* @preempt: Is the associated write serialization lock preemtpible?
/**
* typedef seqcount_LOCKNAME_t - sequence counter with spinlock associated
* @seqcount: The real sequence counter
* @lock: Pointer to the associated spinlock
*
* A plain sequence counter with external writer synchronization by a
* spinlock. The spinlock is associated to the sequence count in the
* static initializer or init function. This enables lockdep to validate
* that the write side critical section is properly serialized.
*/
#define SEQCOUNT_LOCKTYPE(locktype, preempt, lockmember) \
static inline seqcount_t * \
__seqcount_##locktype##_ptr(seqcount_##locktype##_t *s) \

/*
* SEQCOUNT_LOCKTYPE() - Instantiate seqcount_LOCKNAME_t and helpers
* @locktype: actual typename
* @lockname: name
* @preemptible: preemptibility of above locktype
* @lockmember: argument for lockdep_assert_held()
*/
#define SEQCOUNT_LOCKTYPE(locktype, lockname, preemptible, lockmember) \
typedef struct seqcount_##lockname { \
seqcount_t seqcount; \
__SEQ_LOCK(locktype *lock); \
} seqcount_##lockname##_t; \
\
static __always_inline seqcount_t * \
__seqcount_##lockname##_ptr(seqcount_##lockname##_t *s) \
{ \
return &s->seqcount; \
} \
\
static inline bool \
__seqcount_##locktype##_preemptible(seqcount_##locktype##_t *s) \
static __always_inline bool \
__seqcount_##lockname##_preemptible(seqcount_##lockname##_t *s) \
{ \
return preempt; \
return preemptible; \
} \
\
static inline void \
__seqcount_##locktype##_assert(seqcount_##locktype##_t *s) \
static __always_inline void \
__seqcount_##lockname##_assert(seqcount_##lockname##_t *s) \
{ \
__SEQ_LOCK(lockdep_assert_held(lockmember)); \
}

/*
* Similar hooks, but for plain seqcount_t
* __seqprop() for seqcount_t
*/

static inline seqcount_t *__seqcount_ptr(seqcount_t *s)
Expand All @@ -351,17 +290,14 @@ static inline void __seqcount_assert(seqcount_t *s)
lockdep_assert_preemption_disabled();
}

/*
* @s: Pointer to seqcount_locktype_t, generated hooks first parameter.
*/
SEQCOUNT_LOCKTYPE(raw_spinlock, false, s->lock)
SEQCOUNT_LOCKTYPE(spinlock, false, s->lock)
SEQCOUNT_LOCKTYPE(rwlock, false, s->lock)
SEQCOUNT_LOCKTYPE(mutex, true, s->lock)
SEQCOUNT_LOCKTYPE(ww_mutex, true, &s->lock->base)

#define __seqprop_case(s, locktype, prop) \
seqcount_##locktype##_t: __seqcount_##locktype##_##prop((void *)(s))
SEQCOUNT_LOCKTYPE(raw_spinlock_t, raw_spinlock, false, s->lock)
SEQCOUNT_LOCKTYPE(spinlock_t, spinlock, false, s->lock)
SEQCOUNT_LOCKTYPE(rwlock_t, rwlock, false, s->lock)
SEQCOUNT_LOCKTYPE(struct mutex, mutex, true, s->lock)
SEQCOUNT_LOCKTYPE(struct ww_mutex, ww_mutex, true, &s->lock->base)

#define __seqprop_case(s, lockname, prop) \
seqcount_##lockname##_t: __seqcount_##lockname##_##prop((void *)(s))

#define __seqprop(s, prop) _Generic(*(s), \
seqcount_t: __seqcount_##prop((void *)(s)), \
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