From 5cdd25572a29e46f932d3e6eedbd07429de66431 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Fri, 4 Sep 2020 17:32:28 +0200 Subject: [PATCH] seqlock: Use unique prefix for seqcount_t property accessors At seqlock.h, the following set of functions: - __seqcount_ptr() - __seqcount_preemptible() - __seqcount_assert() act as plain seqcount_t "property" accessors. Meanwhile, the following group: - __seqcount_ptr() - __seqcount_lock_preemptible() - __seqcount_assert_lock_held() act as the equivalent set, but in the generic form, taking either seqcount_t or any of the seqcount_LOCKNAME_t variants. This is quite confusing, especially the first member where it is called exactly the same in both groups. Differentiate the first group by using "__seqprop" as prefix, and also use that same prefix for all of seqcount_LOCKNAME_t property accessors. While at it, constify the property accessors first parameter when appropriate. References: 55f3560df975 ("seqlock: Extend seqcount API with associated locks") Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200904153231.11994-3-a.darwish@linutronix.de --- include/linux/seqlock.h | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index 820ace2f5911..0b4a22f33ac3 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -157,7 +157,9 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s) */ /* - * SEQCOUNT_LOCKNAME() - Instantiate seqcount_LOCKNAME_t and helpers + * SEQCOUNT_LOCKNAME() - Instantiate seqcount_LOCKNAME_t and helpers + * seqprop_LOCKNAME_*() - Property accessors for seqcount_LOCKNAME_t + * * @lockname: "LOCKNAME" part of seqcount_LOCKNAME_t * @locktype: LOCKNAME canonical C data type * @preemptible: preemptibility of above lockname @@ -177,19 +179,19 @@ seqcount_##lockname##_init(seqcount_##lockname##_t *s, locktype *lock) \ } \ \ static __always_inline seqcount_t * \ -__seqcount_##lockname##_ptr(seqcount_##lockname##_t *s) \ +__seqprop_##lockname##_ptr(seqcount_##lockname##_t *s) \ { \ return &s->seqcount; \ } \ \ static __always_inline bool \ -__seqcount_##lockname##_preemptible(seqcount_##lockname##_t *s) \ +__seqprop_##lockname##_preemptible(const seqcount_##lockname##_t *s) \ { \ return preemptible; \ } \ \ static __always_inline void \ -__seqcount_##lockname##_assert(seqcount_##lockname##_t *s) \ +__seqprop_##lockname##_assert(const seqcount_##lockname##_t *s) \ { \ __SEQ_LOCK(lockdep_assert_held(lockmember)); \ } @@ -198,17 +200,17 @@ __seqcount_##lockname##_assert(seqcount_##lockname##_t *s) \ * __seqprop() for seqcount_t */ -static inline seqcount_t *__seqcount_ptr(seqcount_t *s) +static inline seqcount_t *__seqprop_ptr(seqcount_t *s) { return s; } -static inline bool __seqcount_preemptible(seqcount_t *s) +static inline bool __seqprop_preemptible(const seqcount_t *s) { return false; } -static inline void __seqcount_assert(seqcount_t *s) +static inline void __seqprop_assert(const seqcount_t *s) { lockdep_assert_preemption_disabled(); } @@ -237,10 +239,10 @@ SEQCOUNT_LOCKNAME(ww_mutex, struct ww_mutex, true, &s->lock->base) #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)) + seqcount_##lockname##_t: __seqprop_##lockname##_##prop((void *)(s)) #define __seqprop(s, prop) _Generic(*(s), \ - seqcount_t: __seqcount_##prop((void *)(s)), \ + seqcount_t: __seqprop_##prop((void *)(s)), \ __seqprop_case((s), raw_spinlock, prop), \ __seqprop_case((s), spinlock, prop), \ __seqprop_case((s), rwlock, prop), \ -- 2.11.0