xfs: factor debug code out of xlog_state_do_callback()

Start making this function readable by lifting the debug code into
a conditional function.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_log.c

@@ -2630,6 +2630,48 @@ xlog_get_lowest_lsn(
 	return lowest_lsn;
 }
 
+#ifdef DEBUG
+/*
+ * Make one last gasp attempt to see if iclogs are being left in limbo.  If the
+ * above loop finds an iclog earlier than the current iclog and in one of the
+ * syncing states, the current iclog is put into DO_CALLBACK and the callbacks
+ * are deferred to the completion of the earlier iclog. Walk the iclogs in order
+ * and make sure that no iclog is in DO_CALLBACK unless an earlier iclog is in
+ * one of the syncing states.
+ *
+ * Note that SYNCING|IOERROR is a valid state so we cannot just check for
+ * ic_state == SYNCING.
+ */
+static void
+xlog_state_callback_check_state(
+	struct xlog		*log)
+{
+	struct xlog_in_core	*first_iclog = log->l_iclog;
+	struct xlog_in_core	*iclog = first_iclog;
+
+	do {
+		ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK);
+		/*
+		 * Terminate the loop if iclogs are found in states
+		 * which will cause other threads to clean up iclogs.
+		 *
+		 * SYNCING - i/o completion will go through logs
+		 * DONE_SYNC - interrupt thread should be waiting for
+		 *              l_icloglock
+		 * IOERROR - give up hope all ye who enter here
+		 */
+		if (iclog->ic_state == XLOG_STATE_WANT_SYNC ||
+		    iclog->ic_state & XLOG_STATE_SYNCING ||
+		    iclog->ic_state == XLOG_STATE_DONE_SYNC ||
+		    iclog->ic_state == XLOG_STATE_IOERROR )
+			break;
+		iclog = iclog->ic_next;
+	} while (first_iclog != iclog);
+}
+#else
+#define xlog_state_callback_check_state(l)	((void)0)
+#endif
+
 STATIC void
 xlog_state_do_callback(
 	struct xlog		*log,
@@ -2804,41 +2846,8 @@ xlog_state_do_callback(
 		}
 	} while (!ioerrors && loopdidcallbacks);
 
-#ifdef DEBUG
-	/*
-	 * Make one last gasp attempt to see if iclogs are being left in limbo.
-	 * If the above loop finds an iclog earlier than the current iclog and
-	 * in one of the syncing states, the current iclog is put into
-	 * DO_CALLBACK and the callbacks are deferred to the completion of the
-	 * earlier iclog. Walk the iclogs in order and make sure that no iclog
-	 * is in DO_CALLBACK unless an earlier iclog is in one of the syncing
-	 * states.
-	 *
-	 * Note that SYNCING|IOABORT is a valid state so we cannot just check
-	 * for ic_state == SYNCING.
-	 */
-	if (funcdidcallbacks) {
-		first_iclog = iclog = log->l_iclog;
-		do {
-			ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK);
-			/*
-			 * Terminate the loop if iclogs are found in states
-			 * which will cause other threads to clean up iclogs.
-			 *
-			 * SYNCING - i/o completion will go through logs
-			 * DONE_SYNC - interrupt thread should be waiting for
-			 *              l_icloglock
-			 * IOERROR - give up hope all ye who enter here
-			 */
-			if (iclog->ic_state == XLOG_STATE_WANT_SYNC ||
-			    iclog->ic_state & XLOG_STATE_SYNCING ||
-			    iclog->ic_state == XLOG_STATE_DONE_SYNC ||
-			    iclog->ic_state == XLOG_STATE_IOERROR )
-				break;
-			iclog = iclog->ic_next;
-		} while (first_iclog != iclog);
-	}
-#endif
+	if (funcdidcallbacks)
+		xlog_state_callback_check_state(log);
 
 	if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR))
 		wake_up_all(&log->l_flush_wait);