target: improve robustness of polling and reexamination

When a target was present on OpenOCD start but later disappeared for
whatever reason (typically unstable connection or target going to
sleep) and reappeared only for a brief period of time, reexamination
would fail, and poll would no longer run. This patch fixes it.

Change-Id: I61f9b5a3f366a761320e233f4e1689f926b5556d
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2370
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Tested-by: jenkins

diff --git a/src/target/target.c b/src/target/target.c
index d7a2c4815de22ee7b75e7bae9f0cd5891e504681..b74c6a0cc920323c3f185907da0894bbbecbc07d 100644 (file)
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -2425,7 +2425,13 @@ static int handle_target(void *priv)
                        if (target->backoff.times > 0) {
                                LOG_USER("Polling target %s succeeded again, trying to reexamine", target_name(target));
                                target_reset_examined(target);
-                               target_examine_one(target);
+                               retval = target_examine_one(target);
+                               /* Target examination could have failed due to unstable connection,
+                                * but we set the examined flag anyway to repoll it later */
+                               if (retval != ERROR_OK) {
+                                       target->examined = true;
+                                       return retval;
+                               }
                        }
 
                        target->backoff.times = 0;