On Sun, 2018-06-03 at 22:09 -0700, Himanshu Madhani wrote: > This patch prevents driver from setting lower default speed > of 1 GB/sec, if the switch does not support Get Port Speed > Capabilities (GPSC) command. Setting this default speed results > into much lower write performance for large sequential WRITE. > This patch modifies driver to check for gpsc_supported flags and > prevents driver from issuing MBC_SET_PORT_PARAM (001Ah) to set > default speed of 1 GB/sec. If driver does not send this mailbox > command, firmware assumes maximum supported link speed and will > operate at the max speed. > > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> > --- > Hi Martin, > > This patch fixes lower write performance for large sequential Writes. > > Please apply this to 4.18-scsi-fixes at your earliest convenience. > > Thanks, > Himanshu > --- > drivers/scsi/qla2xxx/qla_init.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c > index 1aa3720ea2ed..b0430a280ce6 100644 > --- a/drivers/scsi/qla2xxx/qla_init.c > +++ b/drivers/scsi/qla2xxx/qla_init.c > @@ -5007,7 +5007,8 @@ qla2x00_iidma_fcport(scsi_qla_host_t *vha, fc_port_t *fcport) > return; > > if (fcport->fp_speed == PORT_SPEED_UNKNOWN || > - fcport->fp_speed > ha->link_data_rate) > + fcport->fp_speed > ha->link_data_rate || > + !ha->flags.gpsc_supported) > return; > > rval = qla2x00_set_idma_speed(vha, fcport->loop_id, fcport->fp_speed, Martin, This patch fixes the issue Eda found in our test environment. Reported-by: Eda Zhou <ezhou@xxxxxxxxxx> Reviewed-by: Ewan D. Milne <emilne@xxxxxxxxxx> Tested-by: Ewan D. Milne <emilne@xxxxxxxxxx>
