kernel/linux.git/fs/btrfs/locking.c, branch v6.18.21

btrfs: fix typos in comments and strings

2025-09-23T06:49:16+00:00

Annual typo fixing pass. Strangely codespell found only about 30% of what is in this patch, the rest was done manually using text spellchecker with a custom dictionary of acceptable terms. Reviewed-by: Neal Gompa Signed-off-by: David Sterba

btrfs: trivial conversion to return bool instead of int

2025-05-15T12:30:49+00:00

Old code has a lot of int for bool return values, bool is recommended and done in new code. Convert the trivial cases that do simple 0/false and 1/true. Functions comment are updated if needed. Reviewed-by: Naohiro Aota Signed-off-by: David Sterba

btrfs: update include and forward declarations in headers

2025-03-18T19:35:43+00:00

Pass over all header files and add missing forward declarations, includes or fix include types. Signed-off-by: David Sterba

btrfs: remove unused btrfs_try_tree_write_lock()

2024-11-11T13:34:14+00:00

btrfs_try_tree_write_lock() has been unused since commit 50b21d7a066f ("btrfs: submit a writeback bio per extent_buffer"). Remove it as we don't need it anymore. Reviewed-by: Christoph Hellwig Reviewed-by: Qu Wenruo Signed-off-by: Dr. David Alan Gilbert Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: change root->root_key.objectid to btrfs_root_id()

2024-05-07T19:31:06+00:00

A comment from Filipe on one of my previous cleanups brought my attention to a new helper we have for getting the root id of a root, which makes it easier to read in the code. The changes where made with the following Coccinelle semantic patch: // @@ expression E,E1; @@ ( E->root_key.objectid = E1 | - E->root_key.objectid + btrfs_root_id(E) ) // Reviewed-by: Filipe Manana Signed-off-by: Josef Bacik Reviewed-by: David Sterba [ minor style fixups ] Signed-off-by: David Sterba

btrfs: avoid pointless wake ups of drew lock readers

2024-05-07T19:31:00+00:00

When unlocking a write lock on a drew lock, at btrfs_drew_write_unlock(), it's pointless to wake up tasks waiting to acquire a read lock if we didn't decrement the 'writers' counter down to 0, since a read lock can only be acquired when the counter reaches a value of 0. Doing so is harmless from a functional point of view, but it's not efficient due to unnecessarily waking up tasks just for them to sleep again on the waitqueue. So change this to wake up readers only if we decremented the 'writers' counter to 0. Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: locking: rename __btrfs_tree_lock() and __btrfs_tree_read_lock()

2024-05-07T19:31:00+00:00

The __btrfs_tree_lock() and __btrfs_tree_read_lock() are using a naming with a double underscore prefix, which is specially not proper for exported functions. Remove the double underscore prefix from their name and add the "_nested" suffix. Reviewed-by: Anand Jain Reviewed-by: Johannes Thumshirn Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: locking: inline btrfs_tree_lock() and btrfs_tree_read_lock()

2024-05-07T19:31:00+00:00

The functions btrfs_tree_lock() and btrfs_tree_read_lock() are very trivial so that can be made inline and avoid call overhead, as they are very often called inside critical sections (when searching a btree for example, attempting to lock a child node/leaf while holding a lock on the parent). So make them static inline, which even reduces the size of the btrfs module a little bit. Before this change: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1718786 156276 16920 1891982 1cde8e fs/btrfs/btrfs.ko After this change: $ size fs/btrfs/btrfs.ko text data bss dec hex filename 1718650 156260 16920 1891830 1cddf6 fs/btrfs/btrfs.ko Running fs_mark also showed a tiny improvement with this script: $ cat test.sh #!/bin/bash DEV=/dev/nullb0 MNT=/mnt/nullb0 FILES=100000 THREADS=$(nproc --all) echo "performance" | \ tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor umount $DEV &> /dev/null mkfs.btrfs -f $DEV mount $DEV $MNT OPTS="-S 0 -L 5 -n $FILES -s 0 -t $THREADS -k" for ((i = 1; i <= $THREADS; i++)); do OPTS="$OPTS -d $MNT/d$i" done fs_mark $OPTS umount $MNT Before this change: FSUse% Count Size Files/sec App Overhead 10 1200000 0 180894.0 10705410 16 2400000 0 228211.4 10765738 23 3600000 0 215969.6 11011072 30 4800000 0 199077.1 11145587 46 6000000 0 176624.1 11658470 After this change: FSUse% Count Size Files/sec App Overhead 10 1200000 0 185312.3 10708377 16 2400000 0 229320.4 10858013 23 3600000 0 217958.7 11006167 30 4800000 0 205122.9 11112899 46 6000000 0 178039.1 11438852 Reviewed-by: Anand Jain Reviewed-by: Johannes Thumshirn Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba

btrfs: change BUG_ON to assertion when verifying lockdep class setup

2024-03-04T15:24:48+00:00

The BUG_ON in btrfs_set_buffer_lockdep_class() is a sanity check of the level which is verified in callers, e.g. when initializing an extent buffer or reading from an eb header. Change it to an assertion as this would not happen unless things are really bad and would fail elsewhere too. Reviewed-by: Josef Bacik Reviewed-by: Anand Jain Signed-off-by: David Sterba

btrfs: remove unused included headers

2024-03-04T15:24:46+00:00

With help of neovim, LSP and clangd we can identify header files that are not actually needed to be included in the .c files. This is focused only on removal (with minor fixups), further cleanups are possible but will require doing the header files properly with forward declarations, minimized includes and include-what-you-use care. Reviewed-by: Josef Bacik Signed-off-by: David Sterba