Commit e68ca752 authored by Bart Van Assche's avatar Bart Van Assche Committed by Doug Ledford
Browse files

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: default avatarBart Van Assche <bart.vanassche@sandisk.com>
Cc: James Bottomley <JBottomley@Odin.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Sebastian Parschauer <sebastian.riemer@profitbricks.com>
Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
parent a44074f1
...@@ -61,6 +61,11 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) ...@@ -61,6 +61,11 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r)
return dev_to_shost(r->dev.parent); 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 * srp_tmo_valid() - check timeout combination validity
* @reconnect_delay: Reconnect delay in seconds. * @reconnect_delay: Reconnect delay in seconds.
...@@ -628,9 +633,11 @@ static enum blk_eh_timer_return srp_timed_out(struct scsi_cmnd *scmd) ...@@ -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_device *sdev = scmd->device;
struct Scsi_Host *shost = sdev->host; struct Scsi_Host *shost = sdev->host;
struct srp_internal *i = to_srp_internal(shost->transportt); 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)); 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; BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED;
} }
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment