[PATCH 2/9] dasd: make number of retries configurable

Martin Schwidefsky
2013-06-03T15:03:15Z

Instead of having the number of retries hard-coded in the various
functions we should be using a default retry value, which can
be modified via sysfs.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
drivers/s390/block/dasd_devmap.c | 41 ++++++++++++++++++++++++++++++++++++++
drivers/s390/block/dasd_diag.c | 3 ++-
drivers/s390/block/dasd_eckd.c | 11 ++++++----
drivers/s390/block/dasd_fba.c | 5 ++++-
drivers/s390/block/dasd_int.h | 3 +++
5 files changed, 57 insertions(+), 6 deletions(-)

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index a71bb8a..bc3e7af 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -1240,6 +1240,46 @@ dasd_expires_store(struct device *dev, struct device_attribute *attr,

static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store);

+static ssize_t
+dasd_retries_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct dasd_device *device;
+ int len;
+
+ device = dasd_device_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(device))
+ return -ENODEV;
+ len = snprintf(buf, PAGE_SIZE, "%lu\n", device->default_retries);
+ dasd_put_device(device);
+ return len;
+}
+
+static ssize_t
+dasd_retries_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct dasd_device *device;
+ unsigned long val;
+
+ device = dasd_device_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(device))
+ return -ENODEV;
+
+ if ((strict_strtoul(buf, 10, &val) != 0) ||
+ (val > DASD_RETRIES_MAX)) {
+ dasd_put_device(device);
+ return -EINVAL;
+ }
+
+ if (val)
+ device->default_retries = val;
+
+ dasd_put_device(device);
+ return count;
+}
+
+static DEVICE_ATTR(retries, 0644, dasd_retries_show, dasd_retries_store);
+
static ssize_t dasd_reservation_policy_show(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -1350,6 +1390,7 @@ static struct attribute * dasd_attrs[] = {
&dev_attr_erplog.attr,
&dev_attr_failfast.attr,
&dev_attr_expires.attr,
+ &dev_attr_retries.attr,
&dev_attr_reservation_policy.attr,
&dev_attr_last_known_reservation_state.attr,
&dev_attr_safe_offline.attr,
diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c
index cc06033..1548422 100644
--- a/drivers/s390/block/dasd_diag.c
+++ b/drivers/s390/block/dasd_diag.c
@@ -359,6 +359,7 @@ dasd_diag_check_device(struct dasd_device *device)
}

device->default_expires = DIAG_TIMEOUT;
+ device->default_retries = DIAG_MAX_RETRIES;

/* Figure out position of label block */
switch (private->rdc_data.vdev_class) {
@@ -555,7 +556,7 @@ static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
recid++;
}
}
- cqr->retries = DIAG_MAX_RETRIES;
+ cqr->retries = memdev->default_retries;
cqr->buildclk = get_tod_clock();
if (blk_noretry_request(req) ||
block->base->features & DASD_FEATURE_FAILFAST)
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index 6a44b27..f4315dc 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -1682,6 +1682,9 @@ dasd_eckd_check_characteristics(struct dasd_device *device)

/* set default timeout */
device->default_expires = DASD_EXPIRES;
+ /* set default retry count */
+ device->default_retries = DASD_RETRIES;
+
if (private->gneq) {
value = 1;
for (i = 0; i < private->gneq->timeout.value; i++)
@@ -2659,7 +2662,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single(
cqr->block = block;
cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */
cqr->lpm = startdev->path_data.ppm;
- cqr->retries = 256;
+ cqr->retries = startdev->default_retries;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;
return cqr;
@@ -2834,7 +2837,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_track(
cqr->block = block;
cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */
cqr->lpm = startdev->path_data.ppm;
- cqr->retries = 256;
+ cqr->retries = startdev->default_retries;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;
return cqr;
@@ -3127,7 +3130,7 @@ static struct dasd_ccw_req *dasd_eckd_build_cp_tpm_track(
cqr->block = block;
cqr->expires = startdev->default_expires * HZ; /* default 5 minutes */
cqr->lpm = startdev->path_data.ppm;
- cqr->retries = 256;
+ cqr->retries = startdev->default_retries;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;
return cqr;
@@ -3330,7 +3333,7 @@ static struct dasd_ccw_req *dasd_raw_build_cp(struct dasd_device *startdev,
cqr->block = block;
cqr->expires = startdev->default_expires * HZ;
cqr->lpm = startdev->path_data.ppm;
- cqr->retries = 256;
+ cqr->retries = startdev->default_retries;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;

diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c
index 4dd0e2f..d232c83 100644
--- a/drivers/s390/block/dasd_fba.c
+++ b/drivers/s390/block/dasd_fba.c
@@ -29,6 +29,8 @@
#endif /* PRINTK_HEADER */
#define PRINTK_HEADER "dasd(fba):"

+#define FBA_DEFAULT_RETRIES 32
+
#define DASD_FBA_CCW_WRITE 0x41
#define DASD_FBA_CCW_READ 0x42
#define DASD_FBA_CCW_LOCATE 0x43
@@ -167,6 +169,7 @@ dasd_fba_check_characteristics(struct dasd_device *device)
}

device->default_expires = DASD_EXPIRES;
+ device->default_retries = FBA_DEFAULT_RETRIES;
device->path_data.opm = LPM_ANYPATH;

readonly = dasd_device_is_ro(device);
@@ -369,7 +372,7 @@ static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
cqr->memdev = memdev;
cqr->block = block;
cqr->expires = memdev->default_expires * HZ; /* default 5 minutes */
- cqr->retries = 32;
+ cqr->retries = memdev->default_retries;
cqr->buildclk = get_tod_clock();
cqr->status = DASD_CQR_FILLED;
return cqr;
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 0785bd9..ad42075 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -224,6 +224,8 @@ struct dasd_ccw_req {
/* default expiration time*/
#define DASD_EXPIRES 300
#define DASD_EXPIRES_MAX 40000000
+#define DASD_RETRIES 256
+#define DASD_RETRIES_MAX 32768

/* per dasd_ccw_req flags */
#define DASD_CQR_FLAGS_USE_ERP 0 /* use ERP for this request */
@@ -466,6 +468,7 @@ struct dasd_device {

/* default expiration time in s */
unsigned long default_expires;
+ unsigned long default_retries;

struct dentry *debugfs_dentry;
struct dasd_profile profile;
--
1.7.9.5