d2d05b8803
Inside set_at_max_writeback_rate() the calculation in following if() check is wrong, if (atomic_inc_return(&c->idle_counter) < atomic_read(&c->attached_dev_nr) * 6) Because each attached backing device has its own writeback thread running and increasing c->idle_counter, the counter increates much faster than expected. The correct calculation should be, (counter / dev_nr) < dev_nr * 6 which equals to, counter < dev_nr * dev_nr * 6 This patch fixes the above mistake with correct calculation, and helper routine idle_counter_exceeded() is added to make code be more clear. Reported-by: Mingzhe Zou <mingzhe.zou@easystack.cn> Signed-off-by: Coly Li <colyli@suse.de> Acked-by: Mingzhe Zou <mingzhe.zou@easystack.cn> Link: https://lore.kernel.org/r/20220919161647.81238-6-colyli@suse.de 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.