From 7eaceaccab5f40bbfda044629a6298616aeaed50 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 10 Mar 2011 08:52:07 +0100 Subject: block: remove per-queue plugging Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe --- fs/buffer.c | 31 ++++--------------------------- 1 file changed, 4 insertions(+), 27 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 2219a76e2caf..f903f2e5b4fe 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -54,23 +54,15 @@ init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private) } EXPORT_SYMBOL(init_buffer); -static int sync_buffer(void *word) +static int sleep_on_buffer(void *word) { - struct block_device *bd; - struct buffer_head *bh - = container_of(word, struct buffer_head, b_state); - - smp_mb(); - bd = bh->b_bdev; - if (bd) - blk_run_address_space(bd->bd_inode->i_mapping); io_schedule(); return 0; } void __lock_buffer(struct buffer_head *bh) { - wait_on_bit_lock(&bh->b_state, BH_Lock, sync_buffer, + wait_on_bit_lock(&bh->b_state, BH_Lock, sleep_on_buffer, TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL(__lock_buffer); @@ -90,7 +82,7 @@ EXPORT_SYMBOL(unlock_buffer); */ void __wait_on_buffer(struct buffer_head * bh) { - wait_on_bit(&bh->b_state, BH_Lock, sync_buffer, TASK_UNINTERRUPTIBLE); + wait_on_bit(&bh->b_state, BH_Lock, sleep_on_buffer, TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL(__wait_on_buffer); @@ -749,7 +741,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) { struct buffer_head *bh; struct list_head tmp; - struct address_space *mapping, *prev_mapping = NULL; + struct address_space *mapping; int err = 0, err2; INIT_LIST_HEAD(&tmp); @@ -783,10 +775,6 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) * wait_on_buffer() will do that for us * through sync_buffer(). */ - if (prev_mapping && prev_mapping != mapping) - blk_run_address_space(prev_mapping); - prev_mapping = mapping; - brelse(bh); spin_lock(lock); } @@ -3138,17 +3126,6 @@ out: } EXPORT_SYMBOL(try_to_free_buffers); -void block_sync_page(struct page *page) -{ - struct address_space *mapping; - - smp_mb(); - mapping = page_mapping(page); - if (mapping) - blk_run_backing_dev(mapping->backing_dev_info, page); -} -EXPORT_SYMBOL(block_sync_page); - /* * There are no bdflush tunables left. But distributions are * still running obsolete flush daemons, so we terminate them here. -- cgit v1.2.2 From 721a9602e6607417c6bc15b18e97a2f35266c690 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 9 Mar 2011 11:56:30 +0100 Subject: block: kill off REQ_UNPLUG With the plugging now being explicitly controlled by the submitter, callers need not pass down unplugging hints to the block layer. If they want to unplug, it's because they manually plugged on their own - in which case, they should just unplug at will. Signed-off-by: Jens Axboe --- fs/buffer.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index f903f2e5b4fe..42534f67d71b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -767,7 +767,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) * still in flight on potentially older * contents. */ - write_dirty_buffer(bh, WRITE_SYNC_PLUG); + write_dirty_buffer(bh, WRITE_SYNC); /* * Kick off IO for the previous mapping. Note @@ -1602,14 +1602,8 @@ EXPORT_SYMBOL(unmap_underlying_metadata); * prevents this contention from occurring. * * If block_write_full_page() is called with wbc->sync_mode == - * WB_SYNC_ALL, the writes are posted using WRITE_SYNC_PLUG; this - * causes the writes to be flagged as synchronous writes, but the - * block device queue will NOT be unplugged, since usually many pages - * will be pushed to the out before the higher-level caller actually - * waits for the writes to be completed. The various wait functions, - * such as wait_on_writeback_range() will ultimately call sync_page() - * which will ultimately call blk_run_backing_dev(), which will end up - * unplugging the device queue. + * WB_SYNC_ALL, the writes are posted using WRITE_SYNC; this + * causes the writes to be flagged as synchronous writes. */ static int __block_write_full_page(struct inode *inode, struct page *page, get_block_t *get_block, struct writeback_control *wbc, @@ -1622,7 +1616,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page, const unsigned blocksize = 1 << inode->i_blkbits; int nr_underway = 0; int write_op = (wbc->sync_mode == WB_SYNC_ALL ? - WRITE_SYNC_PLUG : WRITE); + WRITE_SYNC : WRITE); BUG_ON(!PageLocked(page)); -- cgit v1.2.2 From 4ee2491ed8569f370bf4c1a4c046a6efb8032bd2 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 17 Mar 2011 10:51:40 +0100 Subject: fs: make fsync_buffers_list() plug It used WRITE_SYNC_PLUG before and potentially submits a batch of IO, so lets enable plugging for this case. Signed-off-by: Jens Axboe --- fs/buffer.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 42534f67d71b..2e6b1a387b7e 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -743,8 +743,10 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) struct list_head tmp; struct address_space *mapping; int err = 0, err2; + struct blk_plug plug; INIT_LIST_HEAD(&tmp); + blk_start_plug(&plug); spin_lock(lock); while (!list_empty(list)) { @@ -781,6 +783,10 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) } } + spin_unlock(lock); + blk_finish_plug(&plug); + spin_lock(lock); + while (!list_empty(&tmp)) { bh = BH_ENTRY(tmp.prev); get_bh(bh); -- cgit v1.2.2 From 250df6ed274d767da844a5d9f05720b804240197 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 22 Mar 2011 22:23:36 +1100 Subject: fs: protect inode->i_state with inode->i_lock Protect inode state transitions and validity checks with the inode->i_lock. This enables us to make inode state transitions independently of the inode_lock and is the first step to peeling away the inode_lock from the code. This requires that __iget() is done atomically with i_state checks during list traversals so that we don't race with another thread marking the inode I_FREEING between the state check and grabbing the reference. Also remove the unlock_new_inode() memory barrier optimisation required to avoid taking the inode_lock when clearing I_NEW. Simplify the code by simply taking the inode->i_lock around the state change and wakeup. Because the wakeup is no longer tricky, remove the wake_up_inode() function and open code the wakeup where necessary. Signed-off-by: Dave Chinner Signed-off-by: Al Viro --- fs/buffer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/buffer.c') diff --git a/fs/buffer.c b/fs/buffer.c index 2219a76e2caf..da666f3148f9 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1144,7 +1144,7 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size) * inode list. * * mark_buffer_dirty() is atomic. It takes bh->b_page->mapping->private_lock, - * mapping->tree_lock and the global inode_lock. + * mapping->tree_lock and mapping->host->i_lock. */ void mark_buffer_dirty(struct buffer_head *bh) { -- cgit v1.2.2