e2dd8aca2d
Split the bio prison into multiple regions, with a separate rbtree and associated lock for each region. To get fast bio prison locking and not damage the performance of discards too much the bio-prison now stipulates that discards should not cross a BIO_PRISON_MAX_RANGE boundary. Because the range of a key (block_end - block_begin) must not exceed BIO_PRISON_MAX_RANGE: break_up_discard_bio() now ensures the data range reflected in PHYSICAL key doesn't exceed BIO_PRISON_MAX_RANGE. And splitting the thin target's discards (handled with VIRTUAL key) is achieved by updating dm-thin.c to set limits->max_discard_sectors in terms of BIO_PRISON_MAX_RANGE _and_ setting the thin and thin-pool targets' max_discard_granularity to true. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@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.