[PATCH 2/2] event/dlb2: poll HW CQ inflights before mapping queue

[Timothy McDaniel]

When attempting to link a port and queue immediately after unlinking,
the CQ inflights may not all be processed. Poll the h/w register for
outstanding inflights instead of reading once, in case the inflights
are still being processed. Also return EBUSY if the inflight
processing is not completed in a suitable amount of time.
Fixes: 1857f1922ce2 ("event/dlb2: use new implementation of resource file")

Signed-off-by: Timothy McDaniel <timothy.mcdan...@intel.com>
---
 drivers/event/dlb2/pf/base/dlb2_resource.c | 23 ++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/event/dlb2/pf/base/dlb2_resource.c 
b/drivers/event/dlb2/pf/base/dlb2_resource.c
index 3661b940c3..d4c49c2992 100644
--- a/drivers/event/dlb2/pf/base/dlb2_resource.c
+++ b/drivers/event/dlb2/pf/base/dlb2_resource.c
@@ -2356,16 +2356,26 @@ static bool dlb2_domain_finish_unmap_port(struct 
dlb2_hw *hw,
 {
        u32 infl_cnt;
        int i;
+       const int max_iters = 1000;
+       const int iter_poll_us = 100;
 
        if (port->num_pending_removals == 0)
                return false;
 
        /*
         * The unmap requires all the CQ's outstanding inflights to be
-        * completed.
+        * completed. Poll up to 100ms.
         */
-       infl_cnt = DLB2_CSR_RD(hw, DLB2_LSP_CQ_LDB_INFL_CNT(hw->ver,
+       for (i = 0; i < max_iters; i++) {
+               infl_cnt = DLB2_CSR_RD(hw, DLB2_LSP_CQ_LDB_INFL_CNT(hw->ver,
                                                       port->id.phys_id));
+
+               if (DLB2_BITS_GET(infl_cnt,
+                                 DLB2_LSP_CQ_LDB_INFL_CNT_COUNT) == 0)
+                       break;
+               rte_delay_us_sleep(iter_poll_us);
+       }
+
        if (DLB2_BITS_GET(infl_cnt, DLB2_LSP_CQ_LDB_INFL_CNT_COUNT) > 0)
                return false;
 
@@ -5316,6 +5326,7 @@ static void dlb2_log_map_qid(struct dlb2_hw *hw,
  * EINVAL - A requested resource is unavailable, invalid port or queue ID, or
  *         the domain is not configured.
  * EFAULT - Internal error (resp->status not set).
+ * EBUSY  - The requested port has outstanding detach operations.
  */
 int dlb2_hw_map_qid(struct dlb2_hw *hw,
                    u32 domain_id,
@@ -5356,8 +5367,12 @@ int dlb2_hw_map_qid(struct dlb2_hw *hw,
         * attempt to complete them. This may be necessary to free up a QID
         * slot for this requested mapping.
         */
-       if (port->num_pending_removals)
-               dlb2_domain_finish_unmap_port(hw, domain, port);
+       if (port->num_pending_removals) {
+               bool bool_ret;
+               bool_ret = dlb2_domain_finish_unmap_port(hw, domain, port);
+               if (!bool_ret)
+                       return -EBUSY;
+       }
 
        ret = dlb2_verify_map_qid_slot_available(port, queue, resp);
        if (ret)
-- 
2.23.0