[openib-general] [PATCH] stored MAD timeout usage changes

[Sean Hefty]

This patch converts stored MAD timeouts from ms to jiffies and changes from keying off a non-zero timeout to using the MAD status value when handling errors and canceling MADs.

- Sean


Index: access/ib_mad_priv.h
===================================================================
--- access/ib_mad_priv.h	(revision 956)
+++ access/ib_mad_priv.h	(working copy)
@@ -120,7 +120,7 @@
 	struct ib_mad_agent *agent;
 	u64 wr_id;			/* client WR ID */
 	u64 tid;
-	int timeout;
+	unsigned long timeout;
 	int refcount;
 	enum ib_wc_status status;
 };
Index: access/ib_mad.c
===================================================================
--- access/ib_mad.c	(revision 956)
+++ access/ib_mad.c	(working copy)
@@ -352,11 +352,10 @@
 
 		mad_send_wr->tid = send_wr->wr.ud.mad_hdr->tid;
 		mad_send_wr->agent = mad_agent;
+		/* Timeout will be updated after send completes. */
 		mad_send_wr->timeout = cur_send_wr->wr.ud.timeout_ms;
-		if (mad_send_wr->timeout)
-			mad_send_wr->refcount = 2;
-		else
-			mad_send_wr->refcount = 1;
+		/* One reference for each work request to QP + response. */
+		mad_send_wr->refcount = 1 + (mad_send_wr->timeout > 0);
 		mad_send_wr->status = IB_WC_SUCCESS;
 
 		/* Reference MAD agent until send completes */
@@ -787,14 +786,10 @@
 
 	list_for_each_entry(mad_send_wr, &mad_agent_priv->send_list,
 			    agent_list) {
-
-		if (mad_send_wr->tid == tid) {
-			/* Verify request is still valid */
-			if (mad_send_wr->status == IB_WC_SUCCESS &&
-			    mad_send_wr->timeout)
-				return mad_send_wr;
-			else
-				return NULL;
+		if (mad_send_wr->tid == tid && mad_send_wr->timeout) {
+			/* Verify request has not been canceled. */
+			return (mad_send_wr->status == IB_WC_SUCCESS) ?
+				mad_send_wr : NULL;
 		}
 	}
 	return NULL;
@@ -823,6 +818,7 @@
 			ib_free_recv_mad(&recv->header.recv_wc);
 			return;
 		}
+		/* Timeout = 0 means that we won't wait for a response. */
 		mad_send_wr->timeout = 0;
 		spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
 
@@ -951,12 +947,8 @@
 	spin_lock_irqsave(&mad_agent_priv->lock, flags);
 	if (mad_send_wc->status != IB_WC_SUCCESS &&
 	    mad_send_wr->status == IB_WC_SUCCESS) {
-
 		mad_send_wr->status = mad_send_wc->status;
-		if (mad_send_wr->timeout) {
-			mad_send_wr->timeout = 0;
-			mad_send_wr->refcount--;
-		}
+		mad_send_wr->refcount -= (mad_send_wr->timeout > 0);
 	}
 
 	/*
@@ -1077,17 +1069,14 @@
 				 &mad_agent_priv->send_list, agent_list) {
 
 		if (mad_send_wr->status == IB_WC_SUCCESS)
-			mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
-
-		if (mad_send_wr->timeout) {
-			mad_send_wr->timeout = 0;
-			mad_send_wr->refcount--;
-		}
+			mad_send_wr->refcount -= (mad_send_wr->timeout > 0);
 
 		if (mad_send_wr->refcount == 0) {
 			list_del(&mad_send_wr->agent_list);
 			list_add_tail(&mad_send_wr->agent_list,
 				      &cancel_list);
+		} else {
+			mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
 		}
 	}
 	spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
@@ -1142,14 +1131,10 @@
 	}
 
 	if (mad_send_wr->status == IB_WC_SUCCESS)
-		mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
-
-	if (mad_send_wr->timeout) {
-		mad_send_wr->timeout = 0;
-		mad_send_wr->refcount--;
-	}
+		mad_send_wr->refcount -= (mad_send_wr->timeout > 0);
 
 	if (mad_send_wr->refcount != 0) {
+		mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
 		spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
 		goto ret;
 	}