diff options
Diffstat (limited to 'include/linux/srcutiny.h')
| -rw-r--r-- | include/linux/srcutiny.h | 47 |
1 files changed, 22 insertions, 25 deletions
diff --git a/include/linux/srcutiny.h b/include/linux/srcutiny.h index 42311ee0334f..cfbfc540cafc 100644 --- a/include/linux/srcutiny.h +++ b/include/linux/srcutiny.h @@ -27,15 +27,14 @@ #include <linux/swait.h> struct srcu_struct { - int srcu_lock_nesting[2]; /* srcu_read_lock() nesting depth. */ + short srcu_lock_nesting[2]; /* srcu_read_lock() nesting depth. */ + short srcu_idx; /* Current reader array element. */ + u8 srcu_gp_running; /* GP workqueue running? */ + u8 srcu_gp_waiting; /* GP waiting for readers? */ struct swait_queue_head srcu_wq; /* Last srcu_read_unlock() wakes GP. */ - unsigned long srcu_gp_seq; /* GP seq # for callback tagging. */ - struct rcu_segcblist srcu_cblist; - /* Pending SRCU callbacks. */ - int srcu_idx; /* Current reader array element. */ - bool srcu_gp_running; /* GP workqueue running? */ - bool srcu_gp_waiting; /* GP waiting for readers? */ + struct rcu_head *srcu_cb_head; /* Pending callbacks: Head. */ + struct rcu_head **srcu_cb_tail; /* Pending callbacks: Tail. */ struct work_struct srcu_work; /* For driving grace periods. */ #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; @@ -47,7 +46,7 @@ void srcu_drive_gp(struct work_struct *wp); #define __SRCU_STRUCT_INIT(name) \ { \ .srcu_wq = __SWAIT_QUEUE_HEAD_INITIALIZER(name.srcu_wq), \ - .srcu_cblist = RCU_SEGCBLIST_INITIALIZER(name.srcu_cblist), \ + .srcu_cb_tail = &name.srcu_cb_head, \ .srcu_work = __WORK_INITIALIZER(name.srcu_work, srcu_drive_gp), \ __SRCU_DEP_MAP_INIT(name) \ } @@ -63,31 +62,29 @@ void srcu_drive_gp(struct work_struct *wp); void synchronize_srcu(struct srcu_struct *sp); -static inline void synchronize_srcu_expedited(struct srcu_struct *sp) +/* + * Counts the new reader in the appropriate per-CPU element of the + * srcu_struct. Can be invoked from irq/bh handlers, but the matching + * __srcu_read_unlock() must be in the same handler instance. Returns an + * index that must be passed to the matching srcu_read_unlock(). + */ +static inline int __srcu_read_lock(struct srcu_struct *sp) { - synchronize_srcu(sp); -} + int idx; -static inline void srcu_barrier(struct srcu_struct *sp) -{ - synchronize_srcu(sp); + idx = READ_ONCE(sp->srcu_idx); + WRITE_ONCE(sp->srcu_lock_nesting[idx], sp->srcu_lock_nesting[idx] + 1); + return idx; } -static inline unsigned long srcu_batches_completed(struct srcu_struct *sp) +static inline void synchronize_srcu_expedited(struct srcu_struct *sp) { - return 0; + synchronize_srcu(sp); } -static inline void srcutorture_get_gp_data(enum rcutorture_type test_type, - struct srcu_struct *sp, int *flags, - unsigned long *gpnum, - unsigned long *completed) +static inline void srcu_barrier(struct srcu_struct *sp) { - if (test_type != SRCU_FLAVOR) - return; - *flags = 0; - *completed = sp->srcu_gp_seq; - *gpnum = *completed; + synchronize_srcu(sp); } #endif |