[libvirt] [PATCH 1/2] Fix logic in xenUnifiedNumOfDomains to match xenUnifiedListDomains

[Daniel P. Berrange]

From: Jonas Eriksson <jonas.j.eriksson at ericsson.com>

The xenUnifiedNumOfDomains and xenUnifiedListDomains methods work
together as a pair, so it is critical they both apply the same
logic. With the current mis-matched logic it is possible to sometimes
get into a state when you miss certain active guests.

* src/xen/xen_driver.c: Change xenUnifiedNumOfDomains ordering to
  match xenUnifiedListDomains.
---
 src/xen/proxy_internal.c |    3 +--
 src/xen/proxy_internal.h |    1 +
 src/xen/xen_driver.c     |   30 ++++++++++++++++++++++++------
 src/xen/xend_internal.c  |    2 +-
 src/xen/xend_internal.h  |    1 +
 5 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/src/xen/proxy_internal.c b/src/xen/proxy_internal.c
index f9d2fad..22ff172 100644
--- a/src/xen/proxy_internal.c
+++ b/src/xen/proxy_internal.c
@@ -40,7 +40,6 @@ static virDrvOpenStatus xenProxyOpen(virConnectPtr conn, virConnectAuthPtr auth,
 static int xenProxyGetVersion(virConnectPtr conn, unsigned long *hvVer);
 static int xenProxyNodeGetInfo(virConnectPtr conn, virNodeInfoPtr info);
 static char *xenProxyGetCapabilities(virConnectPtr conn);
-static int xenProxyNumOfDomains(virConnectPtr conn);
 static unsigned long xenProxyDomainGetMaxMemory(virDomainPtr domain);
 static int xenProxyDomainGetInfo(virDomainPtr domain, virDomainInfoPtr info);
 static char *xenProxyDomainGetOSType(virDomainPtr domain);
@@ -607,7 +606,7 @@ xenProxyListDomains(virConnectPtr conn, int *ids, int maxids)
  *
  * Returns the number of domain found or -1 in case of error
  */
-static int
+int
 xenProxyNumOfDomains(virConnectPtr conn)
 {
     virProxyPacket req;
diff --git a/src/xen/proxy_internal.h b/src/xen/proxy_internal.h
index 185fa67..19df751 100644
--- a/src/xen/proxy_internal.h
+++ b/src/xen/proxy_internal.h
@@ -96,4 +96,5 @@ extern char *       xenProxyDomainDumpXML(virDomainPtr domain,
                                           int flags);
 extern int          xenProxyListDomains(virConnectPtr conn, int *ids,
                                         int maxids);
+extern int xenProxyNumOfDomains(virConnectPtr conn);
 #endif /* __LIBVIR_PROXY_H__ */
diff --git a/src/xen/xen_driver.c b/src/xen/xen_driver.c
index 76b896a..fc8bbe6 100644
--- a/src/xen/xen_driver.c
+++ b/src/xen/xen_driver.c
@@ -576,13 +576,31 @@ static int
 xenUnifiedNumOfDomains (virConnectPtr conn)
 {
     GET_PRIVATE(conn);
-    int i, ret;
+    int ret;
 
-    for (i = 0; i < XEN_UNIFIED_NR_DRIVERS; ++i)
-        if (priv->opened[i] && drivers[i]->numOfDomains) {
-            ret = drivers[i]->numOfDomains (conn);
-            if (ret >= 0) return ret;
-        }
+    /* Try xenstore. */
+    if (priv->opened[XEN_UNIFIED_XS_OFFSET]) {
+        ret = xenStoreNumOfDomains (conn);
+        if (ret >= 0) return ret;
+    }
+
+    /* Try HV. */
+    if (priv->opened[XEN_UNIFIED_HYPERVISOR_OFFSET]) {
+        ret = xenHypervisorNumOfDomains (conn);
+        if (ret >= 0) return ret;
+    }
+
+    /* Try xend. */
+    if (priv->opened[XEN_UNIFIED_XEND_OFFSET]) {
+        ret = xenDaemonNumOfDomains (conn);
+        if (ret >= 0) return ret;
+    }
+
+    /* Try proxy. */
+    if (priv->opened[XEN_UNIFIED_PROXY_OFFSET]) {
+        ret = xenProxyNumOfDomains (conn);
+        if (ret >= 0) return ret;
+    }
 
     return -1;
 }
diff --git a/src/xen/xend_internal.c b/src/xen/xend_internal.c
index 49bdba9..f362ae6 100644
--- a/src/xen/xend_internal.c
+++ b/src/xen/xend_internal.c
@@ -3685,7 +3685,7 @@ error:
  *
  * Returns the number of domain found or -1 in case of error
  */
-static int
+int
 xenDaemonNumOfDomains(virConnectPtr conn)
 {
     struct sexpr *root = NULL;
diff --git a/src/xen/xend_internal.h b/src/xen/xend_internal.h
index 9d2571b..8b00737 100644
--- a/src/xen/xend_internal.h
+++ b/src/xen/xend_internal.h
@@ -187,5 +187,6 @@ int xenDaemonDomainMigratePerform (virDomainPtr domain, const char *cookie, int
 
 int xenDaemonDomainBlockPeek (virDomainPtr domain, const char *path, unsigned long long offset, size_t size, void *buffer);
 int xenDaemonListDomains(virConnectPtr conn, int *ids, int maxids);
+int xenDaemonNumOfDomains(virConnectPtr conn);
 
 #endif /* __XEND_INTERNAL_H_ */
-- 
1.6.2.5