Makes Dept able to track dependencies by seqlock with adding wait
annotation on read side of seqlock.
Signed-off-by: Byungchul Park <byungchul.park@xxxxxxx>
---
include/linux/seqlock.h | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 37ded6b..35929c9 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -23,6 +23,13 @@
#include <asm/processor.h>
+#ifdef CONFIG_DEPT
+#define DEPT_EVT_ALL ((1UL << DEPT_MAX_SUBCLASSES_EVT) - 1)
+#define dept_seq_wait(m, ip) dept_wait(m, DEPT_EVT_ALL, ip, __func__, 0)
+#else
+#define dept_seq_wait(m, ip) do { } while (0)
+#endif
+
/*
* The seqlock seqcount_t interface does not prescribe a precise sequence of
* read begin/retry/end. For readers, typically there is a call to
@@ -148,7 +155,7 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
* This lock-unlock technique must be implemented for all of PREEMPT_RT
* sleeping locks. See Documentation/locking/locktypes.rst
*/
-#if defined(CONFIG_LOCKDEP) || defined(CONFIG_PREEMPT_RT)
+#if defined(CONFIG_LOCKDEP) || defined(CONFIG_DEPT) || defined(CONFIG_PREEMPT_RT)
#define __SEQ_LOCK(expr) expr
#else
#define __SEQ_LOCK(expr)
@@ -203,6 +210,12 @@ static inline void seqcount_lockdep_reader_access(const seqcount_t *s)
__SEQ_LOCK(locktype *lock); \
} seqcount_##lockname##_t; \
\
+static __always_inline void \
+__seqprop_##lockname##_wait(const seqcount_##lockname##_t *s) \
+{ \
+ __SEQ_LOCK(dept_seq_wait(&(lockmember)->dep_map.dmap, _RET_IP_));\
+} \
+ \
static __always_inline seqcount_t * \
__seqprop_##lockname##_ptr(seqcount_##lockname##_t *s) \
{ \
@@ -271,6 +284,8 @@ static inline void __seqprop_assert(const seqcount_t *s)
lockdep_assert_preemption_disabled();
}
+static inline void __seqprop_wait(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))
@@ -311,6 +326,7 @@ static inline void __seqprop_assert(const seqcount_t *s)
#define seqprop_sequence(s) __seqprop(s, sequence)
#define seqprop_preemptible(s) __seqprop(s, preemptible)
#define seqprop_assert(s) __seqprop(s, assert)
+#define seqprop_dept_wait(s) __seqprop(s, wait)
/**
* __read_seqcount_begin() - begin a seqcount_t read section w/o barrier
@@ -360,6 +376,7 @@ static inline void __seqprop_assert(const seqcount_t *s)
#define read_seqcount_begin(s) \
({ \
seqcount_lockdep_reader_access(seqprop_ptr(s)); \
+ seqprop_dept_wait(s); \
raw_read_seqcount_begin(s); \
})
--
1.9.1
