xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[SCSI] Add 'eh_deadline' to limit SCSI EH runtime

Browse Source 
This patchs adds an 'eh_deadline' sysfs attribute to the scsi
host which limits the overall runtime of the SCSI EH.
The 'eh_deadline' value is stored in the now obsolete field
'resetting'.
When a command is failed the start time of the EH is stored
in 'last_reset'. If the overall runtime of the SCSI EH is longer
than last_reset + eh_deadline, the EH is short-circuited and
falls through to issue a host reset only.

[jejb: add comments in Scsi_Host about new fields]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Hannes Reinecke
2013-10-23 10:51:21 +02:00
committed by James Bottomley
parent 6b1e5a45d4
commit b45620229d
4 changed files with 173 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

37
drivers/scsi/scsi_sysfs.c
View File

@@ -281,6 +281,42 @@ exit_store_host_reset:
static DEVICE_ATTR(host_reset, S_IWUSR, NULL, store_host_reset);
static ssize_t
show_shost_eh_deadline(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct Scsi_Host *shost = class_to_shost(dev);
return sprintf(buf, "%d\n", shost->eh_deadline / HZ);
}
static ssize_t
store_shost_eh_deadline(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct Scsi_Host *shost = class_to_shost(dev);
int ret = -EINVAL;
int deadline;
unsigned long flags;
if (shost->transportt && shost->transportt->eh_strategy_handler)
return ret;
if (sscanf(buf, "%d\n", &deadline) == 1) {
spin_lock_irqsave(shost->host_lock, flags);
if (scsi_host_in_recovery(shost))
ret = -EBUSY;
else {
shost->eh_deadline = deadline * HZ;
ret = count;
}
spin_unlock_irqrestore(shost->host_lock, flags);
}
return ret;
}
static DEVICE_ATTR(eh_deadline, S_IRUGO | S_IWUSR, show_shost_eh_deadline, store_shost_eh_deadline);
shost_rd_attr(unique_id, "%u\n");
shost_rd_attr(host_busy, "%hu\n");
shost_rd_attr(cmd_per_lun, "%hd\n");
@@ -308,6 +344,7 @@ static struct attribute *scsi_sysfs_shost_attrs[] = {
&dev_attr_prot_capabilities.attr,
&dev_attr_prot_guard_type.attr,
&dev_attr_host_reset.attr,
&dev_attr_eh_deadline.attr,
NULL
};