IB/ehca: Refactor "maybe missed event" code

Refactor the ehca changes from commit ed23a727 ("IB: Return "maybe
missed event" hint from ib_req_notify_cq()") so the queue arithmetic
is done in slightly fewer lines.  Also, move the spinlock flags into
the block they're used in.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 11 insertions, 19 deletions

diff --git a/drivers/infiniband/hw/ehca/ehca_reqs.c b/drivers/infiniband/hw/ehca/ehca_reqs.c
index caec9dee09e1..56c4527c884f 100644
--- a/drivers/infiniband/hw/ehca/ehca_reqs.c
+++ b/drivers/infiniband/hw/ehca/ehca_reqs.c
@@ -637,7 +637,6 @@ poll_cq_exit0:
 int ehca_req_notify_cq(struct ib_cq *cq, enum ib_cq_notify_flags notify_flags)
 {
         struct ehca_cq *my_cq = container_of(cq, struct ehca_cq, ib_cq);
-        unsigned long spl_flags;
         int ret = 0;
 
         switch (notify_flags & IB_CQ_SOLICITED_MASK) {
@@ -652,6 +651,7 @@ int ehca_req_notify_cq(struct ib_cq *cq, enum ib_cq_notify_flags notify_flags)
         }
 
         if (notify_flags & IB_CQ_REPORT_MISSED_EVENTS) {
+                unsigned long spl_flags;
                 spin_lock_irqsave(&my_cq->spinlock, spl_flags);
                 ret = ipz_qeit_is_valid(&my_cq->ipz_queue);
                 spin_unlock_irqrestore(&my_cq->spinlock, spl_flags);
diff --git a/drivers/infiniband/hw/ehca/ipz_pt_fn.h b/drivers/infiniband/hw/ehca/ipz_pt_fn.h
index 57f141a36bce..007f0882fd40 100644
--- a/drivers/infiniband/hw/ehca/ipz_pt_fn.h
+++ b/drivers/infiniband/hw/ehca/ipz_pt_fn.h
@@ -105,7 +105,6 @@ void *ipz_qpageit_get_inc(struct ipz_queue *queue);
  * step in struct ipz_queue, will wrap in ringbuffer
  * returns address (kv) of Queue Entry BEFORE increment
  * warning don't use in parallel with ipz_qpageit_get_inc()
- * warning unpredictable results may occur if steps>act_nr_of_queue_entries
  */
 static inline void *ipz_qeit_get_inc(struct ipz_queue *queue)
 {
@@ -121,31 +120,24 @@ static inline void *ipz_qeit_get_inc(struct ipz_queue *queue)
 }
 
 /*
+ * return a bool indicating whether current Queue Entry is valid
+ */
+static inline int ipz_qeit_is_valid(struct ipz_queue *queue)
+{
+        struct ehca_cqe *cqe = ipz_qeit_get(queue);
+        return ((cqe->cqe_flags >> 7) == (queue->toggle_state & 1));
+}
+
+/*
  * return current Queue Entry, increment Queue Entry iterator by one
  * step in struct ipz_queue, will wrap in ringbuffer
  * returns address (kv) of Queue Entry BEFORE increment
  * returns 0 and does not increment, if wrong valid state
  * warning don't use in parallel with ipz_qpageit_get_inc()
- * warning unpredictable results may occur if steps>act_nr_of_queue_entries
  */
 static inline void *ipz_qeit_get_inc_valid(struct ipz_queue *queue)
 {
-        struct ehca_cqe *cqe = ipz_qeit_get(queue);
-        u32 cqe_flags = cqe->cqe_flags;
-
-        if ((cqe_flags >> 7) != (queue->toggle_state & 1))
-                return NULL;
-
-        ipz_qeit_get_inc(queue);
-        return cqe;
-}
-
-static inline int ipz_qeit_is_valid(struct ipz_queue *queue)
-{
-        struct ehca_cqe *cqe = ipz_qeit_get(queue);
-        u32 cqe_flags = cqe->cqe_flags;
-
-        return cqe_flags >> 7 == (queue->toggle_state & 1);
+        return ipz_qeit_is_valid(queue) ? ipz_qeit_get_inc(queue) : NULL;
 }
 
 /*