This allows a list of requests to be issued, with the LLD only writing the hardware doorbell when necessary, after the last request was prepared. This is more efficient if we have lists of requests to issue, particularly on virtualized hardware, where writing the doorbell is more expensive than on real hardware. This applies to any HBA, either singlequeue or multiqueue; the second patch implements it for virtio-scsi. Paolo Paolo Bonzini (2): scsi_host: add support for request batching virtio_scsi: implement request batching drivers/scsi/scsi_lib.c | 37 ++++++++++++++++++++++--- drivers/scsi/virtio_scsi.c | 55 +++++++++++++++++++++++++++----------- include/scsi/scsi_cmnd.h | 1 + include/scsi/scsi_host.h | 16 +++++++++-- 4 files changed, 89 insertions(+), 20 deletions(-) -- 2.21.0
