- 25 Sep, 2008 40 commits
-
-
Chris Mason authored
A btree block cow has two parts, the first is to allocate a destination block and the second is to copy the old bock over. The first part needs locks in the extent allocation tree, and may need to do IO. This changeset splits that into a separate function that can be called without any tree locks held. btrfs_search_slot is changed to drop its path and start over if it has to COW a contended block. This often means that many writers will pre-alloc a new destination for a the same contended block, but they cache their prealloc for later use on lower levels in the tree. Signed-off-by:Chris Mason <chris.mason@oracle.com>
-
Chris Mason authored
Signed-off-by: -
Chris Mason authored
While dropping snapshots, walk_down_tree does most of the work of checking reference counts and limiting tree traversal to just the blocks that we are freeing. It dropped and held the allocation mutex in strange and confusing ways, this commit changes it to only hold the mutex while actually freeing a block. The rest of the checks around reference counts should be safe without the lock because we only allow one process in btrfs_drop_snapshot at a time. Other processes dropping reference counts should not drop it to 1 because their tree roots already have an extra ref on the block. Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
Large streaming reads make for large bios, which means each entry on the list async work queues represents a large amount of data. IO congestion throttling on the device was kicking in before the async worker threads decided a single thread was busy and needed some help. The end result was that a streaming read would result in a single CPU running at 100% instead of balancing the work off to other CPUs. This patch also changes the pre-IO checksum lookup done by reads to work on a per-bio basis instead of a per-page. This results in many extra btree lookups on large streaming reads. Doing the checksum lookup right before bio submit allows us to reuse searches while processing adjacent offsets. Signed-off-by: -
Chris Mason authored
This avoids waiting for transactions with pages locked by breaking out the code to wait for the current transaction to close into a function called by btrfs_throttle. It also lowers the limits for where we start throttling. Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Sven Wegener authored
Add a couple of #if's to follow API changes. Signed-off-by:
Sven Wegener <sven.wegener@stealer.net> Signed-off-by:
-
Yan authored
The memory reclaiming issue happens when snapshot exists. In that case, some cache entries may not be used during old snapshot dropping, so they will remain in the cache until umount. The patch adds a field to struct btrfs_leaf_ref to record create time. Besides, the patch makes all dead roots of a given snapshot linked together in order of create time. After a old snapshot was completely dropped, we check the dead root list and remove all cache entries created before the oldest dead root in the list. Signed-off-by: -
Chris Mason authored
It was incorrectly clearing the up to date flag on the buffer even when the buffer properly verified. Signed-off-by: -
Yan Zheng authored
To check whether a given file extent is referenced by multiple snapshots, the checker walks down the fs tree through dead root and checks all tree blocks in the path. We can easily detect whether a given tree block is directly referenced by other snapshot. We can also detect any indirect reference from other snapshot by checking reference's generation. The checker can always detect multiple references, but can't reliably detect cases of single reference. So btrfs may do file data cow even there is only one reference. Signed-off-by: -
Li Zefan authored
When kthread_run() returns failure, this worker hasn't been added to the list, so btrfs_stop_workers() won't free it. Signed-off-by:
Li Zefan <lizf@cn.fujitsu.com> Signed-off-by:
-
Chris Mason authored
A large reference cache is directly related to a lot of work pending for the cleaner thread. This throttles back new operations based on the size of the reference cache so the cleaner thread will be able to keep up. Overall, this actually makes the FS faster because the cleaner thread will be more likely to find things in cache. Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
This changes the reference cache to make a single cache per root instead of one cache per transaction, and to key by the byte number of the disk block instead of the keys inside. This makes it much less likely to have cache misses if a snapshot or something has an extra reference on a higher node or a leaf while the first transaction that added the leaf into the cache is dropping. Some throttling is added to functions that free blocks heavily so they wait for old transactions to drop. Signed-off-by: -
Yan Zheng authored
Much of the IO done while dropping snapshots is done looking up leaves in the filesystem trees to see if they point to any extents and to drop the references on any extents found. This creates a cache so that IO isn't required. Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Mark Fasheh authored
The 'char name[BTRFS_PATH_NAME_MAX]' member of struct btrfs_ioctl_vol_args is passed directly to strlen() after being copied from user. I haven't verified this, but in theory a userspace program could pass in an unterminated string and cause a kernel crash as strlen walks off the end of the array. This patch terminates the ->name string in all btrfs ioctl functions which currently use a 'struct btrfs_ioctl_vol_args'. Since the string is now properly terminated, it's length will never be longer than BTRFS_PATH_NAME_MAX so that error check has been removed. By the way, it might be better overall to just have the ioctl pass an unterminated string + length structure but I didn't bother with that since it'd change the kernel/user interface. Signed-off-by:
Mark Fasheh <mfasheh@suse.com> Signed-off-by:
-
Yan authored
We should decrease the found slot by one as btrfs_search_slot does when bin_search return 1 and node level > 0. Signed-off-by: -
Yan authored
Inode ref item can be in the next leaf when we find "path->slots[0] == btrfs_header_nritems(...)". Signed-off-by: -
Yan authored
When buffer isn't uptodate, pin_down_bytes may leave the tree locked after it returns. Signed-off-by: -
Balaji Rao authored
Remove a unused variable 'path' in fixup_tree_root_location. Signed-off-by:
Balaji Rao <balajirrao@gmail.com> Signed-off-by:
-
Josef Bacik authored
Signed-off-by: -
Josef Bacik authored
Signed-off-by: -
Josef Bacik authored
Signed-off-by: -
Josef Bacik authored
Signed-off-by: -
Josef Bacik authored
Signed-off-by: -
Chris Mason authored
Before setting an extent to delalloc, the code needs to wait for pending ordered extents. Also, the relocation code needs to wait for ordered IO before scanning the block group again. This is because the extents are not removed until the IO for the new extents is finished Signed-off-by: -
David Woodhouse authored
On UP systems spin_trylock always succeeds Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
Checksum items are not inserted into the tree until all of the io from a given extent is complete. This means one dirty page from an extent may be written, freed, and then read again before the entire extent is on disk and the checksum item is inserted. The checksums themselves are stored in the ordered extent so they can be inserted in bulk when IO is complete. On read, if a checksum item isn't found, the ordered extents were being searched for a checksum record. This all worked most of the time, but the checksum insertion code tries to reduce the number of tree operations by pre-inserting checksum items based on i_size and a few other factors. This means the read code might find a checksum item that hasn't yet really been filled in. This commit changes things to check the ordered extents first and only dive into the btree if nothing was found. This removes the need for extra locking and is more reliable. Signed-off-by: -
Chris Mason authored
The ordered extents have to fit in memory, so an unsigned long is sufficient. Signed-off-by: -
Chris Mason authored
Signed-off-by: -
Chris Mason authored
This releases the alloc_mutex in a few places that hold it for over long operations. btrfs_lookup_block_group is changed so that it doesn't need the mutex at all. Signed-off-by: -
Chris Mason authored
This helps prevent stalls, especially while the snapshot cleaner is running hard Signed-off-by: -
Chris Mason authored
Lockdep has the notion of locking subclasses so that you can identify locks you expect to be taken after other locks of the same class. This changes the per-extent buffer btree locking routines to use a subclass based on the level in the tree. Unfortunately, lockdep can only handle 8 total subclasses, and the btrfs max level is also 8. So when lockdep is on, use a lower max level. Signed-off-by: -
Chris Mason authored
Stress testing was showing data checksum errors, most of which were caused by a lookup bug in the extent_map tree. The tree was caching the last pointer returned, and searches would check the last pointer first. But, search callers also expect the search to return the very first matching extent in the range, which wasn't always true with the last pointer usage. For now, the code to cache the last return value is just removed. It is easy to fix, but I think lookups are rare enough that it isn't required anymore. This commit also replaces do_sync_mapping_range with a local copy of the related functions. Signed-off-by: -
Chris Mason authored
This replaces the use of the page cache lock bit for locking, which wasn't suitable for block size < page size and couldn't be used recursively. The mutexes alone don't fix either problem, but they are the first step. Signed-off-by:
-
