path: root/drivers/scsi/pm8001/pm8001_sas.c
diff options
authorDan Williams <dan.j.williams@intel.com>2011-12-19 16:42:34 -0800
committerJames Bottomley <JBottomley@Parallels.com>2012-02-19 13:48:51 -0600
commitb1124cd3ec97406c767b90bf7e93ecd2d2915592 (patch)
treed0936775aacff4492177c14a73175738dfb51ee0 /drivers/scsi/pm8001/pm8001_sas.c
parentf8daa6e6d83f60a721752cb53433bfdc1503b45f (diff)
[SCSI] libsas: introduce sas_drain_work()
When an lldd invokes ->notify_port_event() it can trigger a chain of libsas events to: 1/ form the port and find the direct attached device 2/ if the attached device is an expander perform domain discovery A call to flush_workqueue() will only flush the initial port formation work. Currently libsas users need to call scsi_flush_work() up to the max depth of chain (which will grow from 2 to 3 when ata discovery is moved to its own discovery event). Instead of open coding multiple calls switch to use drain_workqueue() to flush sas work. drain_workqueue() does not handle new work submitted during the drain so libsas needs a bit of infrastructure to hold off unchained work submissions while a drain is in flight. A lldd ->notify() event is considered 'unchained' while a sas_discover_event() is 'chained'. As Tejun notes: "For now, I think it would be best to add private wrapper in libsas to support deferring unchained work items while draining." Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/pm8001/pm8001_sas.c')
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index 9589fc941a8b..50837933a1e5 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -256,12 +256,14 @@ void pm8001_scan_start(struct Scsi_Host *shost)
int pm8001_scan_finished(struct Scsi_Host *shost, unsigned long time)
+ struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
/* give the phy enabling interrupt event time to come in (1s
* is empirically about all it takes) */
if (time < HZ)
return 0;
/* Wait for discovery to finish */
- scsi_flush_work(shost);
+ sas_drain_work(ha);
return 1;