From b45620229dd67ff1daffa8adce57f37b37860f78 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Wed, 23 Oct 2013 10:51:21 +0200 Subject: [SCSI] Add 'eh_deadline' to limit SCSI EH runtime 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 Signed-off-by: James Bottomley --- drivers/scsi/hosts.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/scsi/hosts.c') diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index df0c3c71ea43..f334859024c0 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -316,6 +316,12 @@ static void scsi_host_dev_release(struct device *dev) kfree(shost); } +static unsigned int shost_eh_deadline; + +module_param_named(eh_deadline, shost_eh_deadline, uint, S_IRUGO|S_IWUSR); +MODULE_PARM_DESC(eh_deadline, + "SCSI EH timeout in seconds (should be between 1 and 2^32-1)"); + static struct device_type scsi_host_type = { .name = "scsi_host", .release = scsi_host_dev_release, @@ -388,6 +394,7 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) shost->unchecked_isa_dma = sht->unchecked_isa_dma; shost->use_clustering = sht->use_clustering; shost->ordered_tag = sht->ordered_tag; + shost->eh_deadline = shost_eh_deadline * HZ; if (sht->supported_mode == MODE_UNKNOWN) /* means we didn't set it ... default to INITIATOR */ -- cgit v1.2.3