In realtime environments, it may be desirable to keep the per-bdi
flusher threads from running on certain cpus. This patch adds a
cpu_list file to /sys/class/bdi/* to enable this. The default is to tie
the flusher threads to the same numa node as the backing device (though
I could be convinced to make it a mask of all cpus to avoid a change in
behaviour).
Thanks to Jeremy Eder for the original idea.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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