From 684999149002dd046269666a390458e0acb38280 Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Fri, 6 Feb 2009 13:52:43 -0700 Subject: [PATCH] Rename struct file->f_ep_lock This lock moves out of the CONFIG_EPOLL ifdef and becomes f_lock. For now, epoll remains the only user, but a future patch will use it to protect f_flags as well. Cc: Davide Libenzi Reviewed-by: Christoph Hellwig Signed-off-by: Jonathan Corbet --- fs/eventpoll.c | 12 +++++++----- fs/file_table.c | 1 + include/linux/eventpoll.h | 1 - include/linux/fs.h | 2 +- 4 files changed, 9 insertions(+), 7 deletions(-) diff --git a/fs/eventpoll.c b/fs/eventpoll.c index 011b9b8c90c6..c5c424f23fd5 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -417,10 +417,10 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi) ep_unregister_pollwait(ep, epi); /* Remove the current item from the list of epoll hooks */ - spin_lock(&file->f_ep_lock); + spin_lock(&file->f_lock); if (ep_is_linked(&epi->fllink)) list_del_init(&epi->fllink); - spin_unlock(&file->f_ep_lock); + spin_unlock(&file->f_lock); rb_erase(&epi->rbn, &ep->rbr); @@ -538,7 +538,7 @@ void eventpoll_release_file(struct file *file) struct epitem *epi; /* - * We don't want to get "file->f_ep_lock" because it is not + * We don't want to get "file->f_lock" because it is not * necessary. It is not necessary because we're in the "struct file" * cleanup path, and this means that noone is using this file anymore. * So, for example, epoll_ctl() cannot hit here sicne if we reach this @@ -547,6 +547,8 @@ void eventpoll_release_file(struct file *file) * will correctly serialize the operation. We do need to acquire * "ep->mtx" after "epmutex" because ep_remove() requires it when called * from anywhere but ep_free(). + * + * Besides, ep_remove() acquires the lock, so we can't hold it here. */ mutex_lock(&epmutex); @@ -785,9 +787,9 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event, goto error_unregister; /* Add the current item to the list of active epoll hook for this file */ - spin_lock(&tfile->f_ep_lock); + spin_lock(&tfile->f_lock); list_add_tail(&epi->fllink, &tfile->f_ep_links); - spin_unlock(&tfile->f_ep_lock); + spin_unlock(&tfile->f_lock); /* * Add the current item to the RB tree. All RB tree operations are diff --git a/fs/file_table.c b/fs/file_table.c index bbeeac6efa1a..aa1e18050282 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -127,6 +127,7 @@ struct file *get_empty_filp(void) atomic_long_set(&f->f_count, 1); rwlock_init(&f->f_owner.lock); f->f_cred = get_cred(cred); + spin_lock_init(&f->f_lock); eventpoll_init_file(f); /* f->f_version: 0 */ return f; diff --git a/include/linux/eventpoll.h b/include/linux/eventpoll.h index f1e1d3c47125..f6856a5a1d4b 100644 --- a/include/linux/eventpoll.h +++ b/include/linux/eventpoll.h @@ -61,7 +61,6 @@ struct file; static inline void eventpoll_init_file(struct file *file) { INIT_LIST_HEAD(&file->f_ep_links); - spin_lock_init(&file->f_ep_lock); } diff --git a/include/linux/fs.h b/include/linux/fs.h index 92734c0012e6..2011600d12c7 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -848,6 +848,7 @@ struct file { #define f_dentry f_path.dentry #define f_vfsmnt f_path.mnt const struct file_operations *f_op; + spinlock_t f_lock; /* f_ep_links */ atomic_long_t f_count; unsigned int f_flags; fmode_t f_mode; @@ -866,7 +867,6 @@ struct file { #ifdef CONFIG_EPOLL /* Used by fs/eventpoll.c to link all the hooks to this file */ struct list_head f_ep_links; - spinlock_t f_ep_lock; #endif /* #ifdef CONFIG_EPOLL */ struct address_space *f_mapping; #ifdef CONFIG_DEBUG_WRITECOUNT