From e68ca75200fed4700471fb84ea0d09e25f269654 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 18 May 2015 13:24:38 +0200 Subject: [PATCH] scsi_transport_srp: Reduce failover time Unlike FC, there is no risk that SCSI devices will be offlined by the SCSI error handler if the SCSI error handler is started while a reconnect attempt is ongoing. Hence report timeout errors as soon as possible if a higher software layer (e.g. multipathd) needs to be informed about a timeout. It is assumed that if both fast_io_fail_tmo < 0 and rport->dev_loss_tmo < 0 that this means that there is no need to report timeouts quickly. Signed-off-by: Bart Van Assche Cc: James Bottomley Cc: Sagi Grimberg Cc: Sebastian Parschauer Signed-off-by: Doug Ledford --- drivers/scsi/scsi_transport_srp.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c index f115f67a6ba5..a85292b1d09d 100644 --- a/drivers/scsi/scsi_transport_srp.c +++ b/drivers/scsi/scsi_transport_srp.c @@ -61,6 +61,11 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) return dev_to_shost(r->dev.parent); } +static inline struct srp_rport *shost_to_rport(struct Scsi_Host *shost) +{ + return transport_class_to_srp_rport(&shost->shost_gendev); +} + /** * srp_tmo_valid() - check timeout combination validity * @reconnect_delay: Reconnect delay in seconds. @@ -628,9 +633,11 @@ static enum blk_eh_timer_return srp_timed_out(struct scsi_cmnd *scmd) struct scsi_device *sdev = scmd->device; struct Scsi_Host *shost = sdev->host; struct srp_internal *i = to_srp_internal(shost->transportt); + struct srp_rport *rport = shost_to_rport(shost); pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev)); - return i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ? + return rport->fast_io_fail_tmo < 0 && rport->dev_loss_tmo < 0 && + i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED; } -- 2.20.1