[PATCH 4/5] seqcount: Compress SEQCNT_LOCKNAME_ZERO()

From: Peter Zijlstra
Date: Wed Jul 29 2020 - 10:02:53 EST


Less is more.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
include/linux/seqlock.h | 63 +++++++++++++-----------------------------------
1 file changed, 18 insertions(+), 45 deletions(-)

--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -138,51 +138,6 @@ static inline void seqcount_lockdep_read
#define __SEQ_LOCK(expr)
#endif

-#define SEQCOUNT_LOCKTYPE_ZERO(seq_name, assoc_lock) { \
- .seqcount = SEQCNT_ZERO(seq_name.seqcount), \
- __SEQ_LOCK(.lock = (assoc_lock)) \
-}
-
-/**
- * SEQCNT_SPINLOCK_ZERO - static initializer for seqcount_spinlock_t
- * @name: Name of the seqcount_spinlock_t instance
- * @lock: Pointer to the associated spinlock
- */
-#define SEQCNT_SPINLOCK_ZERO(name, lock) \
- SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
-/**
- * SEQCNT_RAW_SPINLOCK_ZERO - static initializer for seqcount_raw_spinlock_t
- * @name: Name of the seqcount_raw_spinlock_t instance
- * @lock: Pointer to the associated raw_spinlock
- */
-#define SEQCNT_RAW_SPINLOCK_ZERO(name, lock) \
- SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
-/**
- * SEQCNT_RWLOCK_ZERO - static initializer for seqcount_rwlock_t
- * @name: Name of the seqcount_rwlock_t instance
- * @lock: Pointer to the associated rwlock
- */
-#define SEQCNT_RWLOCK_ZERO(name, lock) \
- SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
-/**
- * SEQCNT_MUTEX_ZERO - static initializer for seqcount_mutex_t
- * @name: Name of the seqcount_mutex_t instance
- * @lock: Pointer to the associated mutex
- */
-#define SEQCNT_MUTEX_ZERO(name, lock) \
- SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
-/**
- * SEQCNT_WW_MUTEX_ZERO - static initializer for seqcount_ww_mutex_t
- * @name: Name of the seqcount_ww_mutex_t instance
- * @lock: Pointer to the associated ww_mutex
- */
-#define SEQCNT_WW_MUTEX_ZERO(name, lock) \
- SEQCOUNT_LOCKTYPE_ZERO(name, lock)
-
/**
* typedef seqcount_LOCKNAME_t - sequence counter with LOCKTYPR associated
* @seqcount: The real sequence counter
@@ -263,6 +218,24 @@ SEQCOUNT_LOCKTYPE(rwlock_t, rwlock, fa
SEQCOUNT_LOCKTYPE(struct mutex, mutex, true, s->lock)
SEQCOUNT_LOCKTYPE(struct ww_mutex, 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
+ */
+
+#define SEQCOUNT_LOCKTYPE_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 __seqprop_case(s, lockname, prop) \
seqcount_##lockname##_t: __seqcount_##lockname##_##prop((void *)(s))