[PATCH] scsi: smartpqi: create module parameters for LUN reset

From: Enzo Matsumiya
Date: Mon Apr 19 2021 - 18:11:52 EST


Commit c2922f174fa0 ("scsi: smartpqi: fix LUN reset when fw bkgnd thread is hung")
added support for a timeout on LUN resets.

However, when there are 2 or more devices connected to the same
controller and you hot-remove one of them, I/O will stall on the
devices still online for PQI_LUN_RESET_RETRIES * PQI_LUN_RESET_RETRY_INTERVAL_MSECS
miliseconds.

This commit makes those values configurable via module parameters.

Changing the bail out condition on rc in _pqi_device_reset() might be possible,
but could also break the original purpose of commit c2922f174fa0.

Signed-off-by: Enzo Matsumiya <ematsumiya@xxxxxxx>
---
drivers/scsi/smartpqi/smartpqi_init.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index a1dacb6e993e..82d96a310efb 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -156,6 +156,18 @@ module_param_named(hide_vsep,
MODULE_PARM_DESC(hide_vsep,
"Hide the virtual SEP for direct attached drives.");

+static int pqi_lun_reset_retries = 3;
+module_param_named(lun_reset_retries,
+ pqi_lun_reset_retries, int, 0644);
+MODULE_PARM_DESC(lun_reset_retries,
+ "Number of retries when resetting a LUN");
+
+static int pqi_lun_reset_tmo_interval = 10000;
+module_param_named(lun_reset_tmo_interval,
+ pqi_lun_reset_tmo_interval, int, 0644);
+MODULE_PARM_DESC(lun_reset_tmo_interval,
+ "LUN reset timeout interval (in miliseconds)");
+
static char *raid_levels[] = {
"RAID-0",
"RAID-4",
@@ -5686,8 +5698,6 @@ static int pqi_lun_reset(struct pqi_ctrl_info *ctrl_info,

/* Performs a reset at the LUN level. */

-#define PQI_LUN_RESET_RETRIES 3
-#define PQI_LUN_RESET_RETRY_INTERVAL_MSECS 10000
#define PQI_LUN_RESET_PENDING_IO_TIMEOUT_SECS 120

static int _pqi_device_reset(struct pqi_ctrl_info *ctrl_info,
@@ -5699,9 +5709,9 @@ static int _pqi_device_reset(struct pqi_ctrl_info *ctrl_info,

for (retries = 0;;) {
rc = pqi_lun_reset(ctrl_info, device);
- if (rc == 0 || ++retries > PQI_LUN_RESET_RETRIES)
+ if (rc == 0 || ++retries > pqi_lun_reset_retries)
break;
- msleep(PQI_LUN_RESET_RETRY_INTERVAL_MSECS);
+ msleep(pqi_lun_reset_tmo_interval);
}

timeout_secs = rc ? PQI_LUN_RESET_PENDING_IO_TIMEOUT_SECS : NO_TIMEOUT;