locking/seqlock: Simplify SEQCOUNT_LOCKNAME()

1. Kill the "lockmember" argument. It is always s->lock plus
   __seqprop_##lockname##_sequence() already uses s->lock and
   ignores "lockmember".

2. Kill the "lock_acquire" argument. __seqprop_##lockname##_sequence()
   can use the same "lockbase" prefix for _lock and _unlock.

Apart from line numbers, gcc -E outputs the same code.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20231012143158.GA16133@redhat.com

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index af518e4d0c6b5655401289ef4c5222f1b556845f..7e7109dbc3f5b6684b380c5d4a4548e32284cecf 100644 (file)
--- 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);                                 \
@@ -216,7 +214,7 @@ __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 +240,7 @@ __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));                       \
 }
 
 /*
@@ -271,10 +269,10 @@ 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