From: emellor@ewan <emellor@ewan>
Date: Tue, 4 Oct 2005 10:27:37 +0000 (+0100)
Subject: Added some DPRINTK statements, for debugging.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~16763^2~55^2
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22Dat/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22Dat?a=commitdiff_plain;h=8ae9ec76309048784e98583a40fba7c577f8ec23;p=xen.git

Added some DPRINTK statements, for debugging.
---

8ae9ec76309048784e98583a40fba7c577f8ec23
diff --cc linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
index c68e7f545a,c68e7f545a..4134c4d71a
--- a/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
+++ b/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
@@@ -63,13 -63,13 +63,23 @@@ static void frontend_changed(struct xen
  	struct backend_info *be
  		= container_of(watch, struct backend_info, watch);
  
++	DPRINTK("frontend_changed: %s.\n", be->frontpath);
++
  	/* If other end is gone, delete ourself. */
  	if (node && !xenbus_exists(be->frontpath, "")) {
++		DPRINTK("Frontend has disappeared; unregistering device.\n");
  		device_unregister(&be->dev->dev);
  		return;
  	}
--	if (be->blkif == NULL || be->blkif->status == CONNECTED)
++	if (be->blkif == NULL) {
++		DPRINTK("blkif is null; doing nothing.\n");
  		return;
++	}
++
++	if (be->blkif->status == CONNECTED) {
++		DPRINTK("blkif is CONNECTED; doing nothing.\n");
++		return;
++	}
  
  	err = xenbus_gather(be->frontpath, "ring-ref", "%lu", &ring_ref,
  			    "event-channel", "%u", &evtchn, NULL);
@@@ -132,10 -132,10 +142,11 @@@ again
  
  	xenbus_dev_ok(be->dev);
  
++	DPRINTK("frontend_changed(%s) finished OK.\n", be->frontpath);
  	return;
--
   abort:
  	xenbus_transaction_end(1);
++	DPRINTK("frontend_changed(%s) aborted.\n", be->frontpath);
  }
  
  /* 
@@@ -152,9 -152,9 +163,13 @@@ static void backend_changed(struct xenb
  		= container_of(watch, struct backend_info, backend_watch);
  	struct xenbus_device *dev = be->dev;
  
++	DPRINTK("backend_changed: %s\n", watch->node);
++
  	err = xenbus_scanf(dev->nodename, "physical-device", "%li", &pdev);
--	if (XENBUS_EXIST_ERR(err))
++	if (XENBUS_EXIST_ERR(err)) {
++		DPRINTK("physical-device node exists; doing nothing.\n");
  		return;
++	}
  	if (err < 0) {
  		xenbus_dev_error(dev, err, "reading physical-device");
  		return;
@@@ -174,6 -174,6 +189,8 @@@
  	}
  
  	if (be->blkif == NULL) {
++		DPRINTK("be->blkif is null; creating VBD.\n");
++
  		/* Front end dir is a number, which is used as the handle. */
  		p = strrchr(be->frontpath, '/') + 1;
  		handle = simple_strtoul(p, NULL, 0);
@@@ -197,6 -197,6 +214,11 @@@
  		/* Pass in NULL node to skip exist test. */
  		frontend_changed(&be->watch, NULL);
  	}
++	else {
++		DPRINTK("be->blkif is non-null; doing nothing.\n");
++	}
++
++	DPRINTK("backend_changed(%s) finished OK.\n", watch->node);
  }
  
  static int blkback_probe(struct xenbus_device *dev,
@@@ -218,8 -218,8 +240,10 @@@
  			    "frontend-id", "%li", &be->frontend_id,
  			    "frontend", NULL, &frontend,
  			    NULL);
--	if (XENBUS_EXIST_ERR(err))
++	if (XENBUS_EXIST_ERR(err)) {
++		DPRINTK("blkback_probe: %s does not exist", dev->nodename);
  		goto free_be;
++	}
  	if (err < 0) {
  		xenbus_dev_error(dev, err,
  				 "reading %s/frontend or frontend-id",
@@@ -231,6 -231,6 +255,8 @@@
  		 * then our bus-id is no longer valid and we need to
  		 * destroy the backend device.
  		 */
++		DPRINTK("blkback_probe: failed to get frontend path and ID; "
++			"destroying backend device");
  		err = -ENOENT;
  		goto free_be;
  	}