[src/trunk]: src/sys/arch/xen/xen When we stall the continuation waiting for ...

[bouyer <bouyer%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/d505c56af752
branches:  trunk
changeset: 748487:d505c56af752
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Sun Oct 25 13:47:43 2009 +0000

description:
When we stall the continuation waiting for the queued I/O to complete
in xbdback_co_cache_flush2(), we don't advance the req pointer. In this
case call xbdi_put() to compensate for the xbdi_get() that will be done again
in xbdback_co_main_loop().
Fix stalled xbdback detach that would stall the whole xenbus thread,
preventing new domU from be created.

diffstat:

 sys/arch/xen/xen/xbdback_xenbus.c |  5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diffs (26 lines):

diff -r 0bf081317873 -r d505c56af752 sys/arch/xen/xen/xbdback_xenbus.c
--- a/sys/arch/xen/xen/xbdback_xenbus.c Sun Oct 25 10:30:47 2009 +0000
+++ b/sys/arch/xen/xen/xbdback_xenbus.c Sun Oct 25 13:47:43 2009 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: xbdback_xenbus.c,v 1.27 2009/10/19 18:41:11 bouyer Exp $      */
+/*      $NetBSD: xbdback_xenbus.c,v 1.28 2009/10/25 13:47:43 bouyer Exp $      */
 
 /*
  * Copyright (c) 2006 Manuel Bouyer.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.27 2009/10/19 18:41:11 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xbdback_xenbus.c,v 1.28 2009/10/25 13:47:43 bouyer Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -987,6 +987,7 @@
        if (xbdi->xbdi_pendingreqs > 0) {
                /* event or iodone will restart processing */
                xbdi->xbdi_cont = NULL;
+               xbdi_put(xbdi);
                return NULL;
        }
        xbdi->xbdi_cont = xbdback_co_cache_doflush;