diff options
| -rw-r--r-- | include/linux/wait.h | 2 | ||||
| -rw-r--r-- | kernel/wait.c | 37 | ||||
| -rw-r--r-- | mm/filemap.c | 40 |
3 files changed, 57 insertions, 22 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index 82068628327f..d9dfd7e32e7b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -139,6 +139,8 @@ void FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *k extern void FASTCALL(__wake_up_locked(wait_queue_head_t *q, unsigned int mode)); extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr)); void FASTCALL(__wake_up_bit(wait_queue_head_t *, void *, int)); +int FASTCALL(__wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, void *, int, int (*)(void *), unsigned)); +int FASTCALL(__wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, void *, int, int (*)(void *), unsigned)); #define wake_up(x) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, NULL) #define wake_up_nr(x, nr) __wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr, NULL) diff --git a/kernel/wait.c b/kernel/wait.c index 78256a812ca0..29057f707dbd 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -143,6 +143,43 @@ int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *arg) } EXPORT_SYMBOL(wake_bit_function); +/* + * To allow interruptible waiting and asynchronous (i.e. nonblocking) + * waiting, the actions of __wait_on_bit() and __wait_on_bit_lock() are + * permitted return codes. Nonzero return codes halt waiting and return. + */ +int __sched fastcall +__wait_on_bit(wait_queue_head_t *wq, struct wait_bit_queue *q, + void *word, int bit, int (*action)(void *), unsigned mode) +{ + int ret = 0; + + prepare_to_wait(wq, &q->wait, mode); + if (test_bit(bit, word)) + ret = (*action)(word); + finish_wait(wq, &q->wait); + return ret; +} +EXPORT_SYMBOL(__wait_on_bit); + +int __sched fastcall +__wait_on_bit_lock(wait_queue_head_t *wq, struct wait_bit_queue *q, + void *word, int bit, int (*action)(void *), unsigned mode) +{ + int ret = 0; + + while (test_and_set_bit(bit, word)) { + prepare_to_wait_exclusive(wq, &q->wait, mode); + if (test_bit(bit, word)) { + if ((ret = (*action)(word))) + break; + } + } + finish_wait(wq, &q->wait); + return ret; +} +EXPORT_SYMBOL(__wait_on_bit_lock); + void fastcall __wake_up_bit(wait_queue_head_t *wq, void *word, int bit) { struct wait_bit_key key = __WAIT_BIT_KEY_INITIALIZER(word, bit); diff --git a/mm/filemap.c b/mm/filemap.c index 6318325e24ca..14159485b57c 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -131,9 +131,12 @@ void remove_from_page_cache(struct page *page) spin_unlock_irq(&mapping->tree_lock); } -static inline int sync_page(struct page *page) +static int sync_page(void *word) { struct address_space *mapping; + struct page *page; + + page = container_of((page_flags_t *)word, struct page, flags); /* * FIXME, fercrissake. What is this barrier here for? @@ -141,7 +144,8 @@ static inline int sync_page(struct page *page) smp_mb(); mapping = page_mapping(page); if (mapping && mapping->a_ops && mapping->a_ops->sync_page) - return mapping->a_ops->sync_page(page); + mapping->a_ops->sync_page(page); + io_schedule(); return 0; } @@ -367,19 +371,19 @@ static wait_queue_head_t *page_waitqueue(struct page *page) return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)]; } +static inline void wake_up_page(struct page *page, int bit) +{ + __wake_up_bit(page_waitqueue(page), &page->flags, bit); +} + void fastcall wait_on_page_bit(struct page *page, int bit_nr) { - wait_queue_head_t *waitqueue = page_waitqueue(page); DEFINE_WAIT_BIT(wait, &page->flags, bit_nr); - prepare_to_wait(waitqueue, &wait.wait, TASK_UNINTERRUPTIBLE); - if (test_bit(bit_nr, &page->flags)) { - sync_page(page); - io_schedule(); - } - finish_wait(waitqueue, &wait.wait); + if (test_bit(bit_nr, &page->flags)) + __wait_on_bit(page_waitqueue(page), &wait, wait.key.flags, + bit_nr, sync_page, TASK_UNINTERRUPTIBLE); } - EXPORT_SYMBOL(wait_on_page_bit); /** @@ -403,7 +407,7 @@ void fastcall unlock_page(struct page *page) if (!TestClearPageLocked(page)) BUG(); smp_mb__after_clear_bit(); - __wake_up_bit(page_waitqueue(page), &page->flags, PG_locked); + wake_up_page(page, PG_locked); } EXPORT_SYMBOL(unlock_page); @@ -419,7 +423,7 @@ void end_page_writeback(struct page *page) BUG(); smp_mb__after_clear_bit(); } - __wake_up_bit(page_waitqueue(page), &page->flags, PG_writeback); + wake_up_page(page, PG_writeback); } EXPORT_SYMBOL(end_page_writeback); @@ -434,19 +438,11 @@ EXPORT_SYMBOL(end_page_writeback); */ void fastcall __lock_page(struct page *page) { - wait_queue_head_t *wqh = page_waitqueue(page); DEFINE_WAIT_BIT(wait, &page->flags, PG_locked); - while (TestSetPageLocked(page)) { - prepare_to_wait_exclusive(wqh, &wait.wait, TASK_UNINTERRUPTIBLE); - if (PageLocked(page)) { - sync_page(page); - io_schedule(); - } - } - finish_wait(wqh, &wait.wait); + __wait_on_bit_lock(page_waitqueue(page), &wait, wait.key.flags, + PG_locked, sync_page, TASK_UNINTERRUPTIBLE); } - EXPORT_SYMBOL(__lock_page); /* |