IB/hfi1: Check xchg returned value for queuing link down entry

Check xchg returned value for queuing link down entry
to guarantee proper atomic value reads.

Fixes: 626c077c02 ("IB/hfi1: Prevent link down request double queuing")
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Sebastian Sanchez 2017-08-13 08:08:22 -07:00 committed by Doug Ledford
parent 028e0a67ea
commit b6422bc012

View File

@ -7810,16 +7810,22 @@ static void handle_8051_interrupt(struct hfi1_devdata *dd, u32 unused, u64 reg)
if (queue_link_down) {
/*
* if the link is already going down or disabled, do not
* queue another
* queue another. If there's a link down entry already
* queued, don't queue another one.
*/
if ((ppd->host_link_state &
(HLS_GOING_OFFLINE | HLS_LINK_COOLDOWN)) ||
ppd->link_enabled == 0 || ppd->is_link_down_queued) {
dd_dev_info(dd, "%s: not queuing link down\n",
__func__);
ppd->link_enabled == 0) {
dd_dev_info(dd, "%s: not queuing link down. host_link_state %x, link_enabled %x\n",
__func__, ppd->host_link_state,
ppd->link_enabled);
} else {
xchg(&ppd->is_link_down_queued, 1);
queue_work(ppd->link_wq, &ppd->link_down_work);
if (xchg(&ppd->is_link_down_queued, 1) == 1)
dd_dev_info(dd,
"%s: link down request already queued\n",
__func__);
else
queue_work(ppd->link_wq, &ppd->link_down_work);
}
}
}