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From: "Ahmed S. Darwish" <a.darwish@linutronix.de>
Date: Fri, 4 Sep 2020 17:32:28 +0200
Subject: [PATCH 10/13] seqlock: Use unique prefix for seqcount_t property
accessors
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.9/older/patches-5.9.1-rt20.tar.xz
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 <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200904153231.11994-3-a.darwish@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
include/linux/seqlock.h | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -170,7 +170,9 @@ static inline void seqcount_lockdep_read
#define seqcount_ww_mutex_init(s, lock) seqcount_LOCKNAME_init(s, lock, ww_mutex);
/*
- * 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
@@ -183,19 +185,19 @@ typedef struct seqcount_##lockname {
} seqcount_##lockname##_t; \
\
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)); \
}
@@ -204,17 +206,17 @@ __seqcount_##lockname##_assert(seqcount_
* __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();
}
@@ -243,10 +245,10 @@ SEQCOUNT_LOCKNAME(ww_mutex, struct ww_mu
#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), \
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