btrfs: refactor btrfs_dec_test_* functions for ordered extents
The refactoring involves the following modifications:
- Return bool instead of int
- Parameter update for @cached of btrfs_dec_test_first_ordered_pending()
For btrfs_dec_test_first_ordered_pending(), @cached is only used to
return the finished ordered extent.
Rename it to @finished_ret.
- Comment updates
* Change one stale comment
Which still refers to btrfs_dec_test_ordered_pending(), but the
context is calling btrfs_dec_test_first_ordered_pending().
* Follow the common comment style for both functions
Add more detailed descriptions for parameters and the return value
* Move the reason why test_and_set_bit() is used into the call sites
- Change how the return value is calculated
The most anti-human part of the return value is:
if (...)
ret = 1;
...
return ret == 0;
This means, when we set ret to 1, the function returns 0.
Change the local variable name to @finished, and directly return the
value of it.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>