From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Justin Tee <justin.tee@broadcom.com>,
"Martin K . Petersen" <martin.petersen@oracle.com>,
Sasha Levin <sashal@kernel.org>,
james.smart@broadcom.com, dick.kennedy@broadcom.com,
jejb@linux.ibm.com, linux-scsi@vger.kernel.org
Subject: [PATCH AUTOSEL 4.19 1/5] scsi: lpfc: Update lpfc_ramp_down_queue_handler() logic
Date: Sun, 7 Apr 2024 09:14:21 -0400 [thread overview]
Message-ID: <20240407131426.1053736-1-sashal@kernel.org> (raw)
From: Justin Tee <justin.tee@broadcom.com>
[ Upstream commit bb011631435c705cdeddca68d5c85fd40a4320f9 ]
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 <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20240305200503.57317-5-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/lpfc/lpfc.h | 1 -
drivers/scsi/lpfc/lpfc_scsi.c | 13 ++++---------
2 files changed, 4 insertions(+), 10 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
index 53b661793268f..5698928d8029c 100644
--- a/drivers/scsi/lpfc/lpfc.h
+++ b/drivers/scsi/lpfc/lpfc.h
@@ -989,7 +989,6 @@ struct lpfc_hba {
unsigned long bit_flags;
#define FABRIC_COMANDS_BLOCKED 0
atomic_t num_rsrc_err;
- atomic_t num_cmd_success;
unsigned long last_rsrc_error_time;
unsigned long last_ramp_down_time;
#ifdef CONFIG_SCSI_LPFC_DEBUG_FS
diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 425b83618a2e5..02d067e1fc45c 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -303,11 +303,10 @@ 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
@@ -322,20 +321,16 @@ 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);
}
/**
--
2.43.0
next reply other threads:[~2024-04-07 13:14 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-07 13:14 Sasha Levin [this message]
2024-04-07 13:14 ` [PATCH AUTOSEL 4.19 5/5] scsi: bnx2fc: Remove spin_lock_bh while releasing resources after upload Sasha Levin
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