903e86f3a6
Commitfbb564a557("lib/sbitmap: Fix invalid loop in __sbitmap_queue_get_batch()") mentioned that "Checking free bits when setting the target bits. Otherwise, it may reuse the busying bits." This commit add check to make sure all masked bits in word before cmpxchg is zero. Then the existing check after cmpxchg to check any zero bit is existing in masked bits in word is redundant. Actually, old value of word before cmpxchg is stored in val and we will filter out busy bits in val by "(get_mask & ~val)" after cmpxchg. So we will not reuse busy bits methioned in commitfbb564a557("lib/sbitmap: Fix invalid loop in __sbitmap_queue_get_batch()"). Revert new-added check to remove redundant check. Fixes:fbb564a557("lib/sbitmap: Fix invalid loop in __sbitmap_queue_get_batch()") Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Link: https://lore.kernel.org/r/20230116205059.3821738-3-shikemeng@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.