describe how to set nr_poll_queues and enable the polling Signed-off-by: Gioh Kim <gi-oh.kim@xxxxxxxxx> Acked-by: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxx> --- Documentation/ABI/testing/sysfs-block-rnbd | 6 ++++++ Documentation/ABI/testing/sysfs-class-rnbd-client | 13 +++++++++++++ 2 files changed, 19 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-block-rnbd b/Documentation/ABI/testing/sysfs-block-rnbd index ec716e1c31a8..80b420b5d6b8 100644 --- a/Documentation/ABI/testing/sysfs-block-rnbd +++ b/Documentation/ABI/testing/sysfs-block-rnbd @@ -56,3 +56,9 @@ Date: Feb 2020 KernelVersion: 5.7 Contact: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxx> Danil Kipnis <danil.kipnis@xxxxxxxxxxxxxxx> Description: Remap the disconnected device if the session is not destroyed yet. + +What: /sys/block/rnbd<N>/rnbd/nr_poll_queues +Date: Feb 2020 +KernelVersion: 5.7 +Contact: Jack Wang <jinpu.wang@xxxxxxxxxxxxxxx> Danil Kipnis <danil.kipnis@xxxxxxxxxxxxxxx> +Description: Contains the number of poll-mode queues diff --git a/Documentation/ABI/testing/sysfs-class-rnbd-client b/Documentation/ABI/testing/sysfs-class-rnbd-client index 2aa05b3e348e..0b5997ab3365 100644 --- a/Documentation/ABI/testing/sysfs-class-rnbd-client +++ b/Documentation/ABI/testing/sysfs-class-rnbd-client @@ -85,6 +85,19 @@ Description: Expected format is the following:: By default "rw" is used. + nr_poll_queues + specifies the number of poll-mode queues. If the IO has HIPRI flag, + the block-layer will send the IO via the poll-mode queue. + For fast network and device the polling is faster than interrupt-base + IO handling because it saves time for context switching, switching to + another process, handling the interrupt and switching back to the + issuing process. + + Set -1 if you want to set it as the number of CPUs + By default rnbd client creates only irq-mode queues. + + NOTICE: MUST make a unique session for a device using the poll-mode queues. + Exit Codes: If the device is already mapped it will fail with EEXIST. If the input -- 2.25.1