fd73a4395d
Optimise the negative xattr lookup with bloom filter. The bit value for the bloom filter map has a reverse semantics for compatibility. That is, the bit value of 0 indicates existence, while the bit value of 1 indicates the absence of corresponding xattr. The initial version is _only_ enabled when xattr_filter_reserved is zero. The filter map internals may change in the future, in which case the reserved flag will be set non-zero and we don't need bothering the compatible bits again at that time. For now disable the optimization if this reserved flag is non-zero. Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Reviewed-by: Chao Yu <chao@kernel.org> Link: https://lore.kernel.org/r/20230722094538.11754-3-jefflexu@linux.alibaba.com Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
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.