[PATCH v2 1/5] seqlock: seqcount_LOCKNAME_t: Standardize naming convention

From: Ahmed S. Darwish
Date: Fri Sep 04 2020 - 11:32:26 EST

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At seqlock.h, sequence counters with associated locks are either called
seqcount_LOCKNAME_t, seqcount_LOCKTYPE_t, or seqcount_locktype_t.

Standardize on seqcount_LOCKNAME_t for all instances in comments,
kernel-doc, and SEQCOUNT_LOCKNAME() generative macro paramters.

Signed-off-by: Ahmed S. Darwish <a.darwish@xxxxxxxxxxxxx>
---
include/linux/seqlock.h | 83 +++++++++++++++++++++--------------------
1 file changed, 42 insertions(+), 41 deletions(-)

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 962d9768945f..4f219df659b1 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -53,7 +53,7 @@
*
* If the write serialization mechanism is one of the common kernel
* locking primitives, use a sequence counter with associated lock
- * (seqcount_LOCKTYPE_t) instead.
+ * (seqcount_LOCKNAME_t) instead.
*
* If it's desired to automatically handle the sequence counter writer
* serialization and non-preemptibility requirements, use a sequential
@@ -117,7 +117,7 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
#define SEQCNT_ZERO(name) { .sequence = 0, SEQCOUNT_DEP_MAP_INIT(name) }

/*
- * Sequence counters with associated locks (seqcount_LOCKTYPE_t)
+ * Sequence counters with associated locks (seqcount_LOCKNAME_t)
*
* A sequence counter which associates the lock used for writer
* serialization at initialization time. This enables lockdep to validate
@@ -138,30 +138,32 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
#endif

/**
- * typedef seqcount_LOCKNAME_t - sequence counter with LOCKTYPR associated
+ * typedef seqcount_LOCKNAME_t - sequence counter with LOCKNAME associated
* @seqcount: The real sequence counter
- * @lock: Pointer to the associated spinlock
+ * @lock: Pointer to the associated lock
*
- * A plain sequence counter with external writer synchronization by a
- * spinlock. The spinlock is associated to the sequence count in the
+ * A plain sequence counter with external writer synchronization by
+ * LOCKNAME @lock. The lock 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.
+ *
+ * LOCKNAME: raw_spinlock, spinlock, rwlock, mutex, or ww_mutex.
*/

/**
* seqcount_LOCKNAME_init() - runtime initializer for seqcount_LOCKNAME_t
* @s: Pointer to the seqcount_LOCKNAME_t instance
- * @lock: Pointer to the associated LOCKTYPE
+ * @lock: Pointer to the associated lock
*/

/*
- * SEQCOUNT_LOCKTYPE() - Instantiate seqcount_LOCKNAME_t and helpers
- * @locktype: actual typename
- * @lockname: name
- * @preemptible: preemptibility of above locktype
+ * SEQCOUNT_LOCKNAME() - Instantiate seqcount_LOCKNAME_t and helpers
+ * @lockname: "LOCKNAME" part of seqcount_LOCKNAME_t
+ * @locktype: LOCKNAME canonical C data type
+ * @preemptible: preemptibility of above lockname
* @lockmember: argument for lockdep_assert_held()
*/
-#define SEQCOUNT_LOCKTYPE(locktype, lockname, preemptible, lockmember) \
+#define SEQCOUNT_LOCKNAME(lockname, locktype, preemptible, lockmember) \
typedef struct seqcount_##lockname { \
seqcount_t seqcount; \
__SEQ_LOCK(locktype *lock); \
@@ -211,29 +213,28 @@ static inline void __seqcount_assert(seqcount_t *s)
lockdep_assert_preemption_disabled();
}

-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)
+SEQCOUNT_LOCKNAME(raw_spinlock, raw_spinlock_t, false, s->lock)
+SEQCOUNT_LOCKNAME(spinlock, spinlock_t, false, s->lock)
+SEQCOUNT_LOCKNAME(rwlock, rwlock_t, false, s->lock)
+SEQCOUNT_LOCKNAME(mutex, struct mutex, true, s->lock)
+SEQCOUNT_LOCKNAME(ww_mutex, struct ww_mutex, true, &s->lock->base)

/**
* SEQCNT_LOCKNAME_ZERO - static initializer for seqcount_LOCKNAME_t
* @name: Name of the seqcount_LOCKNAME_t instance
- * @lock: Pointer to the associated LOCKTYPE
+ * @lock: Pointer to the associated LOCKNAME
*/

-#define SEQCOUNT_LOCKTYPE_ZERO(seq_name, assoc_lock) { \
+#define SEQCOUNT_LOCKNAME_ZERO(seq_name, assoc_lock) { \
.seqcount = SEQCNT_ZERO(seq_name.seqcount), \
__SEQ_LOCK(.lock = (assoc_lock)) \
}

-#define SEQCNT_SPINLOCK_ZERO(name, lock) SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-#define SEQCNT_RAW_SPINLOCK_ZERO(name, lock) SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-#define SEQCNT_RWLOCK_ZERO(name, lock) SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-#define SEQCNT_MUTEX_ZERO(name, lock) SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-#define SEQCNT_WW_MUTEX_ZERO(name, lock) SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
+#define SEQCNT_SPINLOCK_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock)
+#define SEQCNT_RAW_SPINLOCK_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock)
+#define SEQCNT_RWLOCK_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock)
+#define SEQCNT_MUTEX_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock)
+#define SEQCNT_WW_MUTEX_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock)

#define __seqprop_case(s, lockname, prop) \
seqcount_##lockname##_t: __seqcount_##lockname##_##prop((void *)(s))
@@ -252,7 +253,7 @@ SEQCOUNT_LOCKTYPE(struct ww_mutex, ww_mutex, true, &s->lock->base)

/**
* __read_seqcount_begin() - begin a seqcount_t read section w/o barrier
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* __read_seqcount_begin is like read_seqcount_begin, but has no smp_rmb()
* barrier. Callers should ensure that smp_rmb() or equivalent ordering is
@@ -283,7 +284,7 @@ static inline unsigned __read_seqcount_t_begin(const seqcount_t *s)

/**
* raw_read_seqcount_begin() - begin a seqcount_t read section w/o lockdep
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* Return: count to be passed to read_seqcount_retry()
*/
@@ -299,7 +300,7 @@ static inline unsigned raw_read_seqcount_t_begin(const seqcount_t *s)

/**
* read_seqcount_begin() - begin a seqcount_t read critical section
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* Return: count to be passed to read_seqcount_retry()
*/
@@ -314,7 +315,7 @@ static inline unsigned read_seqcount_t_begin(const seqcount_t *s)

/**
* raw_read_seqcount() - read the raw seqcount_t counter value
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* raw_read_seqcount opens a read critical section of the given
* seqcount_t, without any lockdep checking, and without checking or
@@ -337,7 +338,7 @@ static inline unsigned raw_read_seqcount_t(const seqcount_t *s)
/**
* raw_seqcount_begin() - begin a seqcount_t read critical section w/o
* lockdep and w/o counter stabilization
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* raw_seqcount_begin opens a read critical section of the given
* seqcount_t. Unlike read_seqcount_begin(), this function will not wait
@@ -365,7 +366,7 @@ static inline unsigned raw_seqcount_t_begin(const seqcount_t *s)

/**
* __read_seqcount_retry() - end a seqcount_t read section w/o barrier
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
* @start: count, from read_seqcount_begin()
*
* __read_seqcount_retry is like read_seqcount_retry, but has no smp_rmb()
@@ -389,7 +390,7 @@ static inline int __read_seqcount_t_retry(const seqcount_t *s, unsigned start)

/**
* read_seqcount_retry() - end a seqcount_t read critical section
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
* @start: count, from read_seqcount_begin()
*
* read_seqcount_retry closes the read critical section of given
@@ -409,7 +410,7 @@ static inline int read_seqcount_t_retry(const seqcount_t *s, unsigned start)

/**
* raw_write_seqcount_begin() - start a seqcount_t write section w/o lockdep
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*/
#define raw_write_seqcount_begin(s) \
do { \
@@ -428,7 +429,7 @@ static inline void raw_write_seqcount_t_begin(seqcount_t *s)

/**
* raw_write_seqcount_end() - end a seqcount_t write section w/o lockdep
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*/
#define raw_write_seqcount_end(s) \
do { \
@@ -448,7 +449,7 @@ static inline void raw_write_seqcount_t_end(seqcount_t *s)
/**
* write_seqcount_begin_nested() - start a seqcount_t write section with
* custom lockdep nesting level
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
* @subclass: lockdep nesting level
*
* See Documentation/locking/lockdep-design.rst
@@ -471,7 +472,7 @@ static inline void write_seqcount_t_begin_nested(seqcount_t *s, int subclass)

/**
* write_seqcount_begin() - start a seqcount_t write side critical section
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* write_seqcount_begin opens a write side critical section of the given
* seqcount_t.
@@ -497,7 +498,7 @@ static inline void write_seqcount_t_begin(seqcount_t *s)

/**
* write_seqcount_end() - end a seqcount_t write side critical section
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* The write section must've been opened with write_seqcount_begin().
*/
@@ -517,7 +518,7 @@ static inline void write_seqcount_t_end(seqcount_t *s)

/**
* raw_write_seqcount_barrier() - do a seqcount_t write barrier
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* This can be used to provide an ordering guarantee instead of the usual
* consistency guarantee. It is one wmb cheaper, because it can collapse
@@ -571,7 +572,7 @@ static inline void raw_write_seqcount_t_barrier(seqcount_t *s)
/**
* write_seqcount_invalidate() - invalidate in-progress seqcount_t read
* side operations
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* After write_seqcount_invalidate, no seqcount_t read side operations
* will complete successfully and see data older than this.
@@ -589,7 +590,7 @@ static inline void write_seqcount_t_invalidate(seqcount_t *s)

/**
* raw_read_seqcount_latch() - pick even/odd seqcount_t latch data copy
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* Use seqcount_t latching to switch between two storage places protected
* by a sequence counter. Doing so allows having interruptible, preemptible,
@@ -614,7 +615,7 @@ static inline int raw_read_seqcount_t_latch(seqcount_t *s)

/**
* raw_write_seqcount_latch() - redirect readers to even/odd copy
- * @s: Pointer to seqcount_t or any of the seqcount_locktype_t variants
+ * @s: Pointer to seqcount_t or any of the seqcount_LOCKNAME_t variants
*
* The latch technique is a multiversion concurrency control method that allows
* queries during non-atomic modifications. If you can guarantee queries never
--
2.28.0

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