staging/hfi1: Convert lock to mutex

The exp_lock lock does not need to be a spinlock as
all its uses are in process context and allowing the
process to sleep when the mutex is contended might
be beneficial.

Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/staging/rdma/hfi1/hfi.h b/drivers/staging/rdma/hfi1/hfi.h
index 51ecf45..53f464c 100644
--- a/drivers/staging/rdma/hfi1/hfi.h
+++ b/drivers/staging/rdma/hfi1/hfi.h
@@ -258,7 +258,7 @@
 	struct exp_tid_set tid_full_list;
 
 	/* lock protecting all Expected TID data */
-	spinlock_t exp_lock;
+	struct mutex exp_lock;
 	/* number of pio bufs for this ctxt (all procs, if shared) */
 	u32 piocnt;
 	/* first pio buffer for this ctxt */