When the FCoE sending side becomes congested libfc tries to reduce the queue depth on the host; however due to the built-in lag before attempting to ramp down the queue depth _again_ the message log is flooded with messages
libfc: queue full, reducing can_queue to 512 With this patch the message is printed only once (ie when it's actually changed). Signed-off-by: Hannes Reinecke <[email protected]> --- drivers/scsi/libfc/fc_fcp.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c index a808e8e..234352da 100644 --- a/drivers/scsi/libfc/fc_fcp.c +++ b/drivers/scsi/libfc/fc_fcp.c @@ -407,11 +407,12 @@ static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport) * can_queue. Eventually we will hit the point where we run * on all reserved structs. */ -static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport) +static bool fc_fcp_can_queue_ramp_down(struct fc_lport *lport) { struct fc_fcp_internal *si = fc_get_scsi_internal(lport); unsigned long flags; int can_queue; + bool changed = false; spin_lock_irqsave(lport->host->host_lock, flags); @@ -427,9 +428,11 @@ static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport) if (!can_queue) can_queue = 1; lport->host->can_queue = can_queue; + changed = true; unlock: spin_unlock_irqrestore(lport->host->host_lock, flags); + return changed; } /* @@ -1896,11 +1899,11 @@ int fc_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *sc_cmd) if (!fc_fcp_lport_queue_ready(lport)) { if (lport->qfull) { - fc_fcp_can_queue_ramp_down(lport); - shost_printk(KERN_ERR, lport->host, - "libfc: queue full, " - "reducing can_queue to %d.\n", - lport->host->can_queue); + if (fc_fcp_can_queue_ramp_down(lport)) + shost_printk(KERN_ERR, lport->host, + "libfc: queue full, " + "reducing can_queue to %d.\n", + lport->host->can_queue); } rc = SCSI_MLQUEUE_HOST_BUSY; goto out; -- 1.8.5.6
