diff --git a/include/spl/sys/rwlock.h b/include/spl/sys/rwlock.h index 408defac20d3..5e052b532a42 100644 --- a/include/spl/sys/rwlock.h +++ b/include/spl/sys/rwlock.h @@ -78,15 +78,9 @@ typedef enum { RW_READER = 2 } krw_t; -/* - * If CONFIG_RWSEM_SPIN_ON_OWNER is defined, rw_semaphore will have an owner - * field, so we don't need our own. - */ typedef struct { struct rw_semaphore rw_rwlock; -#ifndef CONFIG_RWSEM_SPIN_ON_OWNER kthread_t *rw_owner; -#endif #ifdef CONFIG_LOCKDEP krw_type_t rw_type; #endif /* CONFIG_LOCKDEP */ @@ -97,31 +91,19 @@ typedef struct { static inline void spl_rw_set_owner(krwlock_t *rwp) { -/* - * If CONFIG_RWSEM_SPIN_ON_OWNER is defined, down_write, up_write, - * downgrade_write and __init_rwsem will set/clear owner for us. - */ -#ifndef CONFIG_RWSEM_SPIN_ON_OWNER rwp->rw_owner = current; -#endif } static inline void spl_rw_clear_owner(krwlock_t *rwp) { -#ifndef CONFIG_RWSEM_SPIN_ON_OWNER rwp->rw_owner = NULL; -#endif } static inline kthread_t * rw_owner(krwlock_t *rwp) { -#ifdef CONFIG_RWSEM_SPIN_ON_OWNER - return (SEM(rwp)->owner); -#else return (rwp->rw_owner); -#endif } #ifdef CONFIG_LOCKDEP @@ -148,62 +130,22 @@ spl_rw_lockdep_on_maybe(krwlock_t *rwp) \ #define spl_rw_lockdep_on_maybe(rwp) #endif /* CONFIG_LOCKDEP */ - static inline int -RW_WRITE_HELD(krwlock_t *rwp) +RW_LOCK_HELD(krwlock_t *rwp) { - return (rw_owner(rwp) == current); + return (spl_rwsem_is_locked(SEM(rwp))); } static inline int -RW_LOCK_HELD(krwlock_t *rwp) +RW_WRITE_HELD(krwlock_t *rwp) { - return (spl_rwsem_is_locked(SEM(rwp))); + return (rw_owner(rwp) == current); } static inline int RW_READ_HELD(krwlock_t *rwp) { - if (!RW_LOCK_HELD(rwp)) - return (0); - - /* - * rw_semaphore cheat sheet: - * - * < 3.16: - * There's no rw_semaphore.owner, so use rwp.owner instead. - * If rwp.owner == NULL then it's a reader - * - * 3.16 - 4.7: - * rw_semaphore.owner added (https://lwn.net/Articles/596656/) - * and CONFIG_RWSEM_SPIN_ON_OWNER introduced. - * If rw_semaphore.owner == NULL then it's a reader - * - * 4.8 - 4.16.16: - * RWSEM_READER_OWNED added as an internal #define. - * (https://lore.kernel.org/patchwork/patch/678590/) - * If rw_semaphore.owner == 1 then it's a reader - * - * 4.16.17 - 4.19: - * RWSEM_OWNER_UNKNOWN introduced as ((struct task_struct *)-1L) - * (https://do-db2.lkml.org/lkml/2018/5/15/985) - * If rw_semaphore.owner == 1 then it's a reader. - * - * 4.20+: - * RWSEM_OWNER_UNKNOWN changed to ((struct task_struct *)-2L) - * (https://lkml.org/lkml/2018/9/6/986) - * If rw_semaphore.owner & 1 then it's a reader, and also the reader's - * task_struct may be embedded in rw_semaphore->owner. - */ -#if defined(CONFIG_RWSEM_SPIN_ON_OWNER) && defined(RWSEM_OWNER_UNKNOWN) - if (RWSEM_OWNER_UNKNOWN == (struct task_struct *)-2L) { - /* 4.20+ kernels with CONFIG_RWSEM_SPIN_ON_OWNER */ - return ((unsigned long) SEM(rwp)->owner & 1); - } -#endif - - /* < 4.20 kernel or !CONFIG_RWSEM_SPIN_ON_OWNER */ - return (rw_owner(rwp) == NULL || (unsigned long) rw_owner(rwp) == 1); + return (RW_LOCK_HELD(rwp) && rw_owner(rwp) == NULL); } /* diff --git a/module/spl/spl-rwlock.c b/module/spl/spl-rwlock.c index 86727ed1957c..886e16924e65 100644 --- a/module/spl/spl-rwlock.c +++ b/module/spl/spl-rwlock.c @@ -119,9 +119,6 @@ rwsem_tryupgrade(struct rw_semaphore *rwsem) if (__rwsem_tryupgrade(rwsem)) { rwsem_release(&rwsem->dep_map, 1, _RET_IP_); rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); -#ifdef CONFIG_RWSEM_SPIN_ON_OWNER - rwsem->owner = current; -#endif return (1); } return (0);