mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-07 20:58:14 -04:00
8b010acb31
In our production environment, we find that mounting a 500M /boot which is umount cleanly needs ~6s. One cause is that ffs() is used by xlog_write_log_records() to decide the buffer size. It can cause a lot of small IO easily when xlog_clear_stale_blocks() needs to wrap around the end of log area and log head block is not power of two. Things are similar in xlog_find_verify_cycle(). The code is able to handed bigger buffer very well, we can use roundup_pow_of_two() to replace ffs() directly to avoid small and sychronous IOs. Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Wang Jianchao <wangjc136@midea.com> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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.