• Christoph Hellwig's avatar
    blk-mq: respect rq_affinity · 38535201
    Christoph Hellwig authored
    The blk-mq code is using it's own version of the I/O completion affinity
    tunables, which causes a few issues:
     - the rq_affinity sysfs file doesn't work for blk-mq devices, even if it
       still is present, thus breaking existing tuning setups.
     - the rq_affinity = 1 mode, which is the defauly for legacy request based
       drivers isn't implemented at all.
     - blk-mq drivers don't implement any completion affinity with the default
       flag settings.
    This patches removes the blk-mq ipi_redirect flag and sysfs file, as well
    as the internal BLK_MQ_F_SHOULD_IPI flag and replaces it with code that
    respects the queue-wide rq_affinity flags and also implements the
    rq_affinity = 1 mode.
    This means I/O completion affinity can now only be tuned block-queue wide
    instead of per context, which seems more sensible to me anyway.
    Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
    Signed-off-by: default avatarJens Axboe <axboe@fb.com>
blk-mq-sysfs.c 9.07 KB