Handling busy responses from the SA

Commit Message

Michael Heinz June 4, 2010, 6:30 p.m. UTC

None

Patch

diff --git a/drivers/infiniband/core/mad.c b/drivers/infiniband/core/mad.c index efca783..05f2930 100644
--- a/drivers/infiniband/core/mad.c
+++ b/drivers/infiniband/core/mad.c
@@ -1815,9 +1815,20 @@  static void ib_mad_complete_recv(struct ib_mad_agent_private *mad_agent_priv,
 	 */
 	/* Complete corresponding request */
 	if (ib_response_mad(mad_recv_wc->recv_buf.mad)) {
+		u16 busy = __be16_to_cpu(mad_recv_wc->recv_buf.mad->mad_hdr.status) &
+					IB_MGMT_MAD_STATUS_BUSY;
+
 		spin_lock_irqsave(&mad_agent_priv->lock, flags);
 		mad_send_wr = ib_find_send_mad(mad_agent_priv, mad_recv_wc);
 		if (mad_send_wr) {
+			if (busy && mad_send_wr->retries_left) {
+				/* Just let the query timeout and have it requeued later */
+				spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
+				ib_free_recv_mad(mad_recv_wc);
+				deref_mad_agent(mad_agent_priv);
+				printk(KERN_NOTICE PFX "Response returned with MAD_STATUS_BUSY\n");
+				return;
+			}
 			ib_mark_mad_done(mad_send_wr);
 			spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
 
diff --git a/include/rdma/ib_mad.h b/include/rdma/ib_mad.h index 2651e93..e9dc4cc 100644
--- a/include/rdma/ib_mad.h
+++ b/include/rdma/ib_mad.h
@@ -77,6 +77,15 @@ 
 
 #define IB_MGMT_MAX_METHODS			128
 
+/* MAD Status field bit masks */
+#define IB_MGMT_MAD_STATUS_SUCCESS						0x0000
+#define IB_MGMT_MAD_STATUS_BUSY							0x0001
+#define IB_MGMT_MAD_STATUS_REDIRECT_REQD				0x0002
+#define IB_MGMT_MAD_STATUS_BAD_VERERSION				0x0004	
+#define IB_MGMT_MAD_STATUS_UNSUPPORTED_METHOD			0x0008	
+#define IB_MGMT_MAD_STATUS_UNSUPPORTED_METHOD_ATTRIB	0x000c
+#define IB_MGMT_MAD_STATUS_INVALID_ATTRIB_VALUE			0x001c
+
 /* RMPP information */
 #define IB_MGMT_RMPP_VERSION			1
 #define IB_MGMT_RMPP_PASSTHRU			255