From bb011631435c705cdeddca68d5c85fd40a4320f9 Mon Sep 17 00:00:00 2001 From: Justin Tee Date: Tue, 5 Mar 2024 12:04:55 -0800 Subject: scsi: lpfc: Update lpfc_ramp_down_queue_handler() logic Typically when an out of resource CQE status is detected, the lpfc_ramp_down_queue_handler() logic is called to help reduce I/O load by reducing an sdev's queue_depth. However, the current lpfc_rampdown_queue_depth() logic does not help reduce queue_depth. num_cmd_success is never updated and is always zero, which means new_queue_depth will always be set to sdev->queue_depth. So, new_queue_depth = sdev->queue_depth - new_queue_depth always sets new_queue_depth to zero. And, scsi_change_queue_depth(sdev, 0) is essentially a no-op. Change the lpfc_ramp_down_queue_handler() logic to set new_queue_depth equal to sdev->queue_depth subtracted from number of times num_rsrc_err was incremented. If num_rsrc_err is >= sdev->queue_depth, then set new_queue_depth equal to 1. Eventually, the frequency of Good_Status frames will signal SCSI upper layer to auto increase the queue_depth back to the driver default of 64 via scsi_handle_queue_ramp_up(). Signed-off-by: Justin Tee Link: https://lore.kernel.org/r/20240305200503.57317-5-justintee8345@gmail.com Signed-off-by: Martin K. Petersen --- drivers/scsi/lpfc/lpfc_scsi.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) (limited to 'drivers/scsi/lpfc/lpfc_scsi.c') diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c index e7bfaa0eb811..fc77f19547de 100644 --- a/drivers/scsi/lpfc/lpfc_scsi.c +++ b/drivers/scsi/lpfc/lpfc_scsi.c @@ -167,11 +167,10 @@ lpfc_ramp_down_queue_handler(struct lpfc_hba *phba) struct Scsi_Host *shost; struct scsi_device *sdev; unsigned long new_queue_depth; - unsigned long num_rsrc_err, num_cmd_success; + unsigned long num_rsrc_err; int i; num_rsrc_err = atomic_read(&phba->num_rsrc_err); - num_cmd_success = atomic_read(&phba->num_cmd_success); /* * The error and success command counters are global per @@ -186,20 +185,16 @@ lpfc_ramp_down_queue_handler(struct lpfc_hba *phba) for (i = 0; i <= phba->max_vports && vports[i] != NULL; i++) { shost = lpfc_shost_from_vport(vports[i]); shost_for_each_device(sdev, shost) { - new_queue_depth = - sdev->queue_depth * num_rsrc_err / - (num_rsrc_err + num_cmd_success); - if (!new_queue_depth) - new_queue_depth = sdev->queue_depth - 1; + if (num_rsrc_err >= sdev->queue_depth) + new_queue_depth = 1; else new_queue_depth = sdev->queue_depth - - new_queue_depth; + num_rsrc_err; scsi_change_queue_depth(sdev, new_queue_depth); } } lpfc_destroy_vport_work_array(phba, vports); atomic_set(&phba->num_rsrc_err, 0); - atomic_set(&phba->num_cmd_success, 0); } /** -- cgit v1.2.3