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 | 68 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 66 insertions(+), 2 deletions(-) diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index 37ded6b..585f45c 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -23,6 +23,31 @@ #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) +#define dept_seq_writebegin(m, ip) \ +do { \ + dept_ecxt_enter(m, 1UL, ip, __func__, "write_seqcount_end", 0);\ + dept_ask_event(m); \ +} while (0) +#define dept_seq_writeend(m, ip) \ +do { \ + dept_event(m, 1UL, ip, __func__); \ + dept_ecxt_exit(m, 1UL, ip); \ +} while (0) +#else +#define dept_seq_wait(m, ip) do { } while (0) +#define dept_seq_writebegin(m, ip) do { } while (0) +#define dept_seq_writeend(m, ip) do { } while (0) +#endif + +#ifdef CONFIG_DEPT +#define SEQ_DMAP_INIT(lockname) .dmap = { .name = #lockname } +#else +#define SEQ_DMAP_INIT(lockname) +#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 @@ -82,7 +107,8 @@ static inline void __seqcount_init(seqcount_t *s, const char *name, #ifdef CONFIG_DEBUG_LOCK_ALLOC # define SEQCOUNT_DEP_MAP_INIT(lockname) \ - .dep_map = { .name = #lockname } + .dep_map = { .name = #lockname, \ + SEQ_DMAP_INIT(lockname) } /** * seqcount_init() - runtime initializer for seqcount_t @@ -148,7 +174,7 @@ 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 +229,22 @@ 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 void \ +__seqprop_##lockname##_writebegin(const seqcount_##lockname##_t *s) \ +{ \ +} \ + \ +static __always_inline void \ +__seqprop_##lockname##_writeend(const seqcount_##lockname##_t *s) \ +{ \ +} \ + \ static __always_inline seqcount_t * \ __seqprop_##lockname##_ptr(seqcount_##lockname##_t *s) \ { \ @@ -271,6 +313,21 @@ static inline void __seqprop_assert(const seqcount_t *s) lockdep_assert_preemption_disabled(); } +static inline void __seqprop_wait(seqcount_t *s) +{ + dept_seq_wait(&s->dep_map.dmap, _RET_IP_); +} + +static inline void __seqprop_writebegin(seqcount_t *s) +{ + dept_seq_writebegin(&s->dep_map.dmap, _RET_IP_); +} + +static inline void __seqprop_writeend(seqcount_t *s) +{ + dept_seq_writeend(&s->dep_map.dmap, _RET_IP_); +} + #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 +368,9 @@ 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) +#define seqprop_dept_writebegin(s) __seqprop(s, writebegin) +#define seqprop_dept_writeend(s) __seqprop(s, writeend) /** * __read_seqcount_begin() - begin a seqcount_t read section w/o barrier @@ -360,6 +420,7 @@ 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); \ }) @@ -512,6 +573,7 @@ static inline void do_raw_write_seqcount_end(seqcount_t *s) preempt_disable(); \ \ do_write_seqcount_begin_nested(seqprop_ptr(s), subclass); \ + seqprop_dept_writebegin(s); \ } while (0) static inline void do_write_seqcount_begin_nested(seqcount_t *s, int subclass) @@ -538,6 +600,7 @@ static inline void do_write_seqcount_begin_nested(seqcount_t *s, int subclass) preempt_disable(); \ \ do_write_seqcount_begin(seqprop_ptr(s)); \ + seqprop_dept_writebegin(s); \ } while (0) static inline void do_write_seqcount_begin(seqcount_t *s) @@ -554,6 +617,7 @@ static inline void do_write_seqcount_begin(seqcount_t *s) */ #define write_seqcount_end(s) \ do { \ + seqprop_dept_writeend(s); \ do_write_seqcount_end(seqprop_ptr(s)); \ \ if (seqprop_preemptible(s)) \ -- 1.9.1