- 19 Jun, 2023 40 commits
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Anand Jain authored
Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
There are three ways the fsid is validated in btrfs_validate_super(): - verify that super_copy::fsid is the same as fs_devices::fsid - if the metadata_uuid flag is set, verify if super_copy::metadata_uuid and fs_devices::metadata_uuid are the same. - a few lines below, often missed out, verify if dev_item::fsid is the same as fs_devices::metadata_uuid. The function btrfs_validate_super() contains multiple if-statements with memcmp() to check UUIDs. This patch consolidates them into a single location. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
We often check if the metadata_uuid is not the same as fsid, and then we check if the given fsid matches the metadata_uuid. This patch refactors this logic into function match_fsid_changed and utilize it. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
Refactor the functions find_fsid() and find_fsid_with_metadata_uuid(), as they currently share a common set of code to compare the fsid and metadata_uuid. Create a common helper function, match_fsid_fs_devices(). Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
Simplify the return type of check_tree_block_fsid() from int (1 or 0) to bool. Its only user is interested in knowing the success or failure. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
Add comment about metadata_uuid in btrfs_fs_devices. No functional change. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
Simplify has_metadata_uuid checks - by localizing the has_metadata_uuid checked within alloc_fs_devices()'s second argument, it improves the code readability. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
We currently have redundant checks for the non-null value of fsid simplify it. And, no one is using alloc_fs_devices() with a NULL metadata_uuid while fsid is not NULL, add an assert() to verify this condition. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Anand Jain authored
Pack bool fsid_change and bool seeding with other bool declarations in the struct btrfs_fs_devices, approximately 6 bytes is saved, depending on the config. before: 512 bytes after: 496 bytes Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Most of the code in write_one_subpage_eb and write_one_eb is shared, so merge the two functions into one. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Instead of locking and unlocking every page or the extent, just add a new EXTENT_BUFFER_READING bit that mirrors EXTENT_BUFFER_WRITEBACK for synchronizing threads trying to read an extent_buffer and to wait for I/O completion. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
The only other place that locks extents on the btree inode is read_extent_buffer_subpage while reading in the partial page for a buffer. This means locking the extent in btrfs_buffer_uptodate does not synchronize with anything on non-subpage file systems, and on subpage file systems it only waits for a parallel read(-ahead) to finish, which seems to be counter to what the callers actually expect. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
The only place that reads in pages and thus marks them uptodate for the btree inode is read_extent_buffer_pages. Which means that either pages are already uptodate from an old buffer when creating a new one in alloc_extent_buffer, or they will be updated by ca call to read_extent_buffer_pages. This means the checks for uptodate pages in read_extent_buffer_pages and read_extent_buffer_subpage are superfluous and can be removed. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
PageError is only used to limit the uptodate check in assert_eb_page_uptodate. But we have a much more useful flag indicating the exact condition we are about with the EXTENT_BUFFER_WRITE_ERR flag, so use that instead and help the kernel toward eventually removing PageError. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
No need to track the number of pages under I/O now that each extent_buffer is read and written using a single bio. For the read side we need to grab an extra reference for the duration of the I/O to prevent eviction, though. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
The checksumming of btree blocks always operates on the entire extent_buffer, and because btree blocks are always allocated contiguously on disk they are never split by btrfs_submit_bio. Simplify the checksumming code by finding the extent_buffer in the btrfs_bio private data instead of trying to search through the bio_vec. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Now that we always use a single bio to write an extent_buffer, the buffer can be passed to the end_io handler as private data. This allows to simplify the metadata write end I/O handler, and merge the subpage end_io handler into the main one. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
The btrfs_bio_ctrl machinery is overkill for writing extent_buffers as we always operate on PAGE_SIZE chunks (or one smaller one for the subpage case) that are contiguous and are guaranteed to fit into a single bio. Replace it with open coded btrfs_bio_alloc, __bio_add_page and btrfs_submit_bio calls. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Locking the pages in lock_extent_buffer_for_io only for the non-subpage case is very confusing. Move it to write_one_eb to mirror the subpage case and simplify the code. Now lock_extent_buffer_for_io does not leave all the pages locked and each is individually locked/unlocked in write_one_eb. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Stop trying to cluster writes of multiple extent_buffers into a single bio. There is no need for that as the blk_plug mechanism used all the way up in writeback_inodes_wb gives us the same I/O pattern even with multiple bios. Removing the clustering simplifies lock_extent_buffer_for_io a lot and will also allow passing the eb as private data to the end I/O handler. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
lock_extent_buffer_for_io never returns a negative error value, so switch the return value to a simple bool. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> [ keep noinline_for_stack ] Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Only subpage metadata reads lock the extent. Don't try to unlock it and waste cycles in the extent tree lookup for PAGE_SIZE or larger metadata. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Now that we always use a single bio to read an extent_buffer, the buffer can be passed to the end_io handler as private data. This allows implementing a much simplified dedicated end I/O handler for metadata reads. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Given that read recovery for data I/O is handled in the storage layer, the mirror_num argument to btrfs_submit_compressed_read is always 0, so remove it. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
The btrfs_bio_ctrl machinery is overkill for reading extent_buffers as we always operate on PAGE_SIZE chunks (or one smaller one for the subpage case) that are contiguous and are guaranteed to fit into a single bio. Replace it with open coded btrfs_bio_alloc, __bio_add_page and btrfs_submit_bio calls in a helper function shared between the subpage and node size >= PAGE_SIZE cases. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Currently read_extent_buffer_pages skips pages that are already uptodate when reading in an extent_buffer. While this reduces the amount of data read, it increases the number of I/O operations as we now need to do multiple I/Os when reading an extent buffer with one or more uptodate pages in the middle of it. On any modern storage device, be that hard drives or SSDs this actually decreases I/O performance. Fortunately this case is pretty rare as the pages are always initially read together and then aged the same way. Besides simplifying the code a bit as-is this will allow for major simplifications to the I/O completion handler later on. Note that the case where all pages are uptodate is still handled by an optimized fast path that does not read any data from disk. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
verify_parent_transid is only called by btrfs_buffer_uptodate, which confusingly inverts the return value. Merge the two functions and reflow the parent_transid so that error handling is in a branch. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Setting the buffer uptodate in a function that is named as a validation helper is a it confusing. Move the call from validate_extent_buffer to the one of its two callers that didn't already have a duplicate call to set_extent_buffer_uptodate. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
Call btrfs_page_clear_uptodate instead of ClearPageUptodate to properly manage the uptodate bit for the subpage case. Reported-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
extent_buffer_under_io is only used in extent_io.c, so mark it static. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Qu Wenruo authored
There is an internal error report that scrub found an error in an orphan inode's data. However there are very limited ways to cleanup such orphan inodes: - btrfs_start_pre_rw_mount() This happens at either mount, or RO->RW switch. This is not a viable solution for root fs which may not be unmounted or RO mounted. Furthermore this doesn't cover every subvolume, it only covers the currently cached subvolumes. - btrfs_lookup_dentry() This happens when we first lookup the subvolume dentry. But dentry can be cached thus it's not ensured to be triggered every time. - create_snapshot() This only happens for the created snapshot, not the source one. This means if we didn't trigger orphan items cleanup, there is really no other way to manually trigger it. Add this step to the START_SYNC ioctl. This is a slight change in the semantics of the ioctl but as sync can be potentially slow and is usually paired with WAIT_SYNC ioctl. The errors are not handled because the main point of the ioctl is the async commit, orphan cleanup is a side effect. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
There's a comment at btrfs_init_new_buffer() that refers to a function named btrfs_clean_tree_block(), however the function was renamed to btrfs_clear_buffer_dirty() in commit 190a8339 ("btrfs: rename btrfs_clean_tree_block to btrfs_clear_buffer_dirty"). So update the comment to refer to the current name. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
The for_rename argument of btrfs_record_unlink_dir() is defined as an integer, but the argument is in fact used as a boolean. So change it to a boolean to make its use more clear. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
There's no point of having a label and goto at btrfs_record_unlink_dir() because the function is trivial and can just return early if we are not in a rename context. So remove the label and goto and instead return early if we are not in a rename. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
Update the comments at btrfs_record_unlink_dir() so that they mention where new names are logged and where old names are removed. Also, while at it make the width of the comments closer to 80 columns and capitalize the sentences and finish them with punctuation. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
At btrfs_record_unlink_dir() we directly check the logged_trans field of the given inodes to check if they were previously logged in the current transaction, and if any of them were, then we can avoid setting the field last_unlink_trans of the directory to the id of the current transaction if we are in a rename path. Avoiding that can later prevent falling back to a transaction commit if anyone attempts to log the directory. However the logged_trans field, store in struct btrfs_inode, is transient, not persisted in the inode item on its subvolume b+tree, so that means that if an inode is evicted and then loaded again, its original value is lost and it's reset to 0. So directly checking the logged_trans field can lead to some false negative, and that only results in a performance impact as mentioned before. Instead of directly checking the logged_trans field of the inodes, use the inode_logged() helper, which will check in the log tree if an inode was logged before in case its logged_trans field has a value of 0. This way we can avoid setting the directory inode's last_unlink_trans and cause future logging attempts of it to fallback to transaction commits. The following test script shows one example where this happens without this patch: $ cat test.sh #!/bin/bash DEV=/dev/nullb0 MNT=/mnt/nullb0 num_init_files=10000 num_new_files=10000 mkfs.btrfs -f $DEV mount -o ssd $DEV $MNT mkdir $MNT/testdir for ((i = 1; i <= $num_init_files; i++)); do echo -n > $MNT/testdir/file_$i done echo -n > $MNT/testdir/foo sync # Add some files so that there's more work in the transaction other # than just renaming file foo. for ((i = 1; i <= $num_new_files; i++)); do echo -n > $MNT/testdir/new_file_$i done # Change the file, fsync it. setfattr -n user.x1 -v 123 $MNT/testdir/foo xfs_io -c "fsync" $MNT/testdir/foo # Now triggger eviction of file foo but no eviction for our test # directory, since it is being used by the process below. This will # set logged_trans of the file's inode to 0 once it is loaded again. ( cd $MNT/testdir while true; do : done ) & pid=$! echo 2 > /proc/sys/vm/drop_caches kill $pid wait $pid # Move foo out of our testdir. This will set last_unlink_trans # of the directory inode to the current transaction, because # logged_trans of both the directory and the file are set to 0. mv $MNT/testdir/foo $MNT/foo # Change file foo again and fsync it. # This fsync will result in a transaction commit because the rename # above has set last_unlink_trans of the parent directory to the id # of the current transaction and because our inode for file foo has # last_unlink_trans set to the current transaction, since it was # evicted and reloaded and it was previously modified in the current # transaction (the xattr addition). xfs_io -c "pwrite 0 64K" $MNT/foo start=$(date +%s%N) xfs_io -c "fsync" $MNT/foo end=$(date +%s%N) dur=$(( (end - start) / 1000000 )) echo "file fsync took: $dur milliseconds" umount $MNT Before this patch: fsync took 19 milliseconds After this patch: fsync took 5 milliseconds Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana authored
At need_log_inode() we directly check the ->logged_trans field of the given inode to check if it was previously logged in the transaction, with the goal of skipping logging the inode again when it's not necessary. The ->logged_trans field in not persisted in the inode item or elsewhere, it's only stored in memory (struct btrfs_inode), so it's transient and lost once the inode is evicted and then loaded again. Once an inode is loaded, we are conservative and set ->logged_trans to 0, which may mean that either the inode was never logged in the current transaction or it was logged but evicted before being loaded again. Instead of checking the inode's ->logged_trans field directly, we can use instead the helper inode_logged(), which will really check if the inode was logged before in the current transaction in case we have a ->logged_trans field with a value of 0. This will prevent unnecessarily logging an inode when it's not needed, and in some cases preventing a transaction commit, in case the logging requires a fallback to a transaction commit. The following test script shows a scenario where due to eviction we fallback a transaction commit when trying to fsync a file that was renamed: $ cat test.sh #!/bin/bash DEV=/dev/nullb0 MNT=/mnt/nullb0 num_init_files=10000 num_new_files=10000 mkfs.btrfs -f $DEV mount -o ssd $DEV $MNT mkdir $MNT/testdir for ((i = 1; i <= $num_init_files; i++)); do echo -n > $MNT/testdir/file_$i done echo -n > $MNT/testdir/foo sync # Add some files so that there's more work in the transaction other # than just renaming file foo. for ((i = 1; i <= $num_new_files; i++)); do echo -n > $MNT/testdir/new_file_$i done # Fsync the directory first. xfs_io -c "fsync" $MNT/testdir # Rename file foo. mv $MNT/testdir/foo $MNT/testdir/bar # Now trigger eviction of the test directory's inode. # Once loaded again, it will have logged_trans set to 0 and # last_unlink_trans set to the current transaction. echo 2 > /proc/sys/vm/drop_caches # Fsync file bar (ex-foo). # Before the patch the fsync would result in a transaction commit # because the inode for file bar has last_unlink_trans set to the # current transaction, so it will attempt to log the parent directory # as well, which will fallback to a full transaction commit because # it also has its last_unlink_trans set to the current transaction, # due to the inode eviction. start=$(date +%s%N) xfs_io -c "fsync" $MNT/testdir/bar end=$(date +%s%N) dur=$(( (end - start) / 1000000 )) echo "file fsync took: $dur milliseconds" umount $MNT Before this patch: fsync took 22 milliseconds After this patch: fsync took 8 milliseconds Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Jiapeng Chong authored
These functions are defined in the scrub.c file, but last callers were removed in e9255d6c ("btrfs: scrub: remove the old scrub recheck code"). fs/btrfs/scrub.c:553:20: warning: unused function 'scrub_stripe_index_and_offset'. fs/btrfs/scrub.c:543:19: warning: unused function 'scrub_nr_raid_mirrors'. Reported-by: Abaci Robot <abaci@linux.alibaba.com> Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4937Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Qu Wenruo authored
[BUG] Smatch reports the following errors related to commit ("btrfs: output affected files when relocation fails"): fs/btrfs/inode.c:283 print_data_reloc_error() error: uninitialized symbol 'ref_level'. [CAUSE] That part of code is mostly copied from scrub, but unfortunately scrub code from the beginning is not doing the error handling properly. The offending code looks like this: do { ret = tree_backref_for_extent(); btrfs_warn_rl(); } while (ret != 1); There are several problems involved: - No error handling If that tree_backref_for_extent() failed, we would output the same error again and again, never really exit as it requires ret == 1 to exit. - Always do one extra output As tree_backref_for_extent() only return > 0 if there is no more backref item. This means after the last item we hit, we would output an invalid error message for ret > 0 case. [FIX] Fix the old code by: - Move @ref_root and @ref_level into the if branch And do not initialize them, so we can catch such uninitialized values just like what we do in the inode.c - Explicitly check the return value of tree_backref_for_extent() And handle ret < 0 and ret > 0 cases properly. - No more do {} while () loop Instead go while (true) {} loop since we will handle @ret manually. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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Christoph Hellwig authored
When btrfs_redirty_list_add redirties a buffer, it also acquires an extra reference that is released on transaction commit. But this is not required as buffers that are dirty or under writeback are never freed (look for calls to extent_buffer_under_io())). Remove the extra reference and the infrastructure used to drop it again. History behind redirty logic: In the first place, it used releasing_list to hold all the to-be-released extent buffers, and decided which buffers to re-dirty at the commit time. Then, in a later version, the behaviour got changed to re-dirty a necessary buffer and add re-dirtied one to the list in btrfs_free_tree_block(). In short, the list was there mostly for the patch series' historical reason. Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> [ add Naohiro's comment regarding history ] Signed-off-by: David Sterba <dsterba@suse.com>
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