From 0fe340a98b584a31b07c664dc5ff0c923730581e Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Fri, 23 Aug 2024 14:47:38 +0200 Subject: [PATCH] inode: port __I_NEW to var event Port the __I_NEW mechanism to use the new var event mechanism. Link: https://lore.kernel.org/r/20240823-work-i_state-v3-4-5cd5fd207a57@kernel.org Reviewed-by: Josef Bacik Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- fs/bcachefs/fs.c | 10 ++++++---- fs/dcache.c | 7 ++++++- fs/inode.c | 32 ++++++++++++++++++++++++-------- include/linux/writeback.h | 3 ++- 4 files changed, 38 insertions(+), 14 deletions(-) diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c index 94c392abef65..c0900c0c0f8a 100644 --- a/fs/bcachefs/fs.c +++ b/fs/bcachefs/fs.c @@ -1644,14 +1644,16 @@ again: break; } } else if (clean_pass && this_pass_clean) { - wait_queue_head_t *wq = bit_waitqueue(&inode->v.i_state, __I_NEW); - DEFINE_WAIT_BIT(wait, &inode->v.i_state, __I_NEW); + struct wait_bit_queue_entry wqe; + struct wait_queue_head *wq_head; - prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE); + wq_head = inode_bit_waitqueue(&wqe, &inode->v, __I_NEW); + prepare_to_wait_event(wq_head, &wqe.wq_entry, + TASK_UNINTERRUPTIBLE); mutex_unlock(&c->vfs_inodes_lock); schedule(); - finish_wait(wq, &wait.wq_entry); + finish_wait(wq_head, &wqe.wq_entry); goto again; } } diff --git a/fs/dcache.c b/fs/dcache.c index 1af75fa68638..894e38cdf4d0 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1908,8 +1908,13 @@ void d_instantiate_new(struct dentry *entry, struct inode *inode) __d_instantiate(entry, inode); WARN_ON(!(inode->i_state & I_NEW)); inode->i_state &= ~I_NEW & ~I_CREATING; + /* + * Pairs with the barrier in prepare_to_wait_event() to make sure + * ___wait_var_event() either sees the bit cleared or + * waitqueue_active() check in wake_up_var() sees the waiter. + */ smp_mb(); - wake_up_bit(&inode->i_state, __I_NEW); + inode_wake_up_bit(inode, __I_NEW); spin_unlock(&inode->i_lock); } EXPORT_SYMBOL(d_instantiate_new); diff --git a/fs/inode.c b/fs/inode.c index 1b0f52ebae27..1aa785421f13 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -734,7 +734,13 @@ static void evict(struct inode *inode) * used as an indicator whether blocking on it is safe. */ spin_lock(&inode->i_lock); - wake_up_bit(&inode->i_state, __I_NEW); + /* + * Pairs with the barrier in prepare_to_wait_event() to make sure + * ___wait_var_event() either sees the bit cleared or + * waitqueue_active() check in wake_up_var() sees the waiter. + */ + smp_mb(); + inode_wake_up_bit(inode, __I_NEW); BUG_ON(inode->i_state != (I_FREEING | I_CLEAR)); spin_unlock(&inode->i_lock); @@ -1146,8 +1152,13 @@ void unlock_new_inode(struct inode *inode) spin_lock(&inode->i_lock); WARN_ON(!(inode->i_state & I_NEW)); inode->i_state &= ~I_NEW & ~I_CREATING; + /* + * Pairs with the barrier in prepare_to_wait_event() to make sure + * ___wait_var_event() either sees the bit cleared or + * waitqueue_active() check in wake_up_var() sees the waiter. + */ smp_mb(); - wake_up_bit(&inode->i_state, __I_NEW); + inode_wake_up_bit(inode, __I_NEW); spin_unlock(&inode->i_lock); } EXPORT_SYMBOL(unlock_new_inode); @@ -1158,8 +1169,13 @@ void discard_new_inode(struct inode *inode) spin_lock(&inode->i_lock); WARN_ON(!(inode->i_state & I_NEW)); inode->i_state &= ~I_NEW; + /* + * Pairs with the barrier in prepare_to_wait_event() to make sure + * ___wait_var_event() either sees the bit cleared or + * waitqueue_active() check in wake_up_var() sees the waiter. + */ smp_mb(); - wake_up_bit(&inode->i_state, __I_NEW); + inode_wake_up_bit(inode, __I_NEW); spin_unlock(&inode->i_lock); iput(inode); } @@ -2348,8 +2364,8 @@ EXPORT_SYMBOL(inode_needs_sync); */ static void __wait_on_freeing_inode(struct inode *inode, bool is_inode_hash_locked) { - wait_queue_head_t *wq; - DEFINE_WAIT_BIT(wait, &inode->i_state, __I_NEW); + struct wait_bit_queue_entry wqe; + struct wait_queue_head *wq_head; /* * Handle racing against evict(), see that routine for more details. @@ -2360,14 +2376,14 @@ static void __wait_on_freeing_inode(struct inode *inode, bool is_inode_hash_lock return; } - wq = bit_waitqueue(&inode->i_state, __I_NEW); - prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE); + wq_head = inode_bit_waitqueue(&wqe, inode, __I_NEW); + prepare_to_wait_event(wq_head, &wqe.wq_entry, TASK_UNINTERRUPTIBLE); spin_unlock(&inode->i_lock); rcu_read_unlock(); if (is_inode_hash_locked) spin_unlock(&inode_hash_lock); schedule(); - finish_wait(wq, &wait.wq_entry); + finish_wait(wq_head, &wqe.wq_entry); if (is_inode_hash_locked) spin_lock(&inode_hash_lock); rcu_read_lock(); diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 56b85841ae4c..8f651bb0a1a5 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -200,7 +200,8 @@ void inode_io_list_del(struct inode *inode); /* writeback.h requires fs.h; it, too, is not included from here. */ static inline void wait_on_inode(struct inode *inode) { - wait_on_bit(&inode->i_state, __I_NEW, TASK_UNINTERRUPTIBLE); + wait_var_event(inode_state_wait_address(inode, __I_NEW), + !(READ_ONCE(inode->i_state) & I_NEW)); } #ifdef CONFIG_CGROUP_WRITEBACK -- 2.25.1