From 1e626437194d3851b6845bc7bdebf814a3433b6e Mon Sep 17 00:00:00 2001
From: Jiri Denemark <jdenemar@redhat.com>
Date: Fri, 16 Sep 2011 13:50:56 +0200
Subject: [PATCH] qemu: Add support for keepalive messages during p2p migration

---
 src/qemu/libvirtd_qemu.aug      |  2 ++
 src/qemu/qemu.conf              | 22 ++++++++++++++++++++++
 src/qemu/qemu_conf.c            | 11 +++++++++++
 src/qemu/qemu_conf.h            |  3 +++
 src/qemu/qemu_migration.c       |  4 ++++
 src/qemu/test_libvirtd_qemu.aug |  6 ++++++
 6 files changed, 48 insertions(+)

diff --git a/src/qemu/libvirtd_qemu.aug b/src/qemu/libvirtd_qemu.aug
index 6c145c7d8..ad34e42da 100644
--- a/src/qemu/libvirtd_qemu.aug
+++ b/src/qemu/libvirtd_qemu.aug
@@ -52,6 +52,8 @@ module Libvirtd_qemu =
                  | int_entry "max_processes"
                  | str_entry "lock_manager"
                  | int_entry "max_queued"
+                 | int_entry "keepalive_interval"
+                 | int_entry "keepalive_count"
 
    (* Each enty in the config is one of the following three ... *)
    let entry = vnc_entry
diff --git a/src/qemu/qemu.conf b/src/qemu/qemu.conf
index 1c14d8fb4..c3f264f4e 100644
--- a/src/qemu/qemu.conf
+++ b/src/qemu/qemu.conf
@@ -317,3 +317,25 @@
 # Note, that job lock is per domain.
 #
 # max_queued = 0
+
+###################################################################
+# Keepalive protocol:
+# This allows qemu driver to detect broken connections to remote
+# libvirtd during peer-to-peer migration.  A keepalive message is
+# sent to the deamon after keepalive_interval seconds of inactivity
+# to check if the deamon is still responding; keepalive_count is a
+# maximum number of keepalive messages that are allowed to be sent
+# to the deamon without getting any response before the connection
+# is considered broken.  In other words, the connection is
+# automatically closed approximately after
+# keepalive_interval * (keepalive_count + 1) seconds since the last
+# message received from the deamon.  If keepalive_interval is set to
+# -1, qemu driver will not send keepalive requests during
+# peer-to-peer migration; however, the remote libvirtd can still
+# send them and source libvirtd will send responses.  When
+# keepalive_count is set to 0, connections will be automatically
+# closed after keepalive_interval seconds of inactivity without
+# sending any keepalive messages.
+#
+#keepalive_interval = 5
+#keepalive_count = 5
diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index 0f98521a0..376611938 100644
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -115,6 +115,9 @@ int qemudLoadDriverConfig(struct qemud_driver *driver,
           virLockManagerPluginNew("nop", NULL, 0)))
         return -1;
 
+    driver->keepAliveInterval = 5;
+    driver->keepAliveCount = 5;
+
     /* Just check the file is readable before opening it, otherwise
      * libvirt emits an error.
      */
@@ -460,6 +463,14 @@ int qemudLoadDriverConfig(struct qemud_driver *driver,
     CHECK_TYPE("max_queued", VIR_CONF_LONG);
     if (p) driver->max_queued = p->l;
 
+    p = virConfGetValue(conf, "keepalive_interval");
+    CHECK_TYPE("keepalive_interval", VIR_CONF_LONG);
+    if (p) driver->keepAliveInterval = p->l;
+
+    p = virConfGetValue(conf, "keepalive_count");
+    CHECK_TYPE("keepalive_count", VIR_CONF_LONG);
+    if (p) driver->keepAliveCount = p->l;
+
     virConfFree (conf);
     return 0;
 }
diff --git a/src/qemu/qemu_conf.h b/src/qemu/qemu_conf.h
index e13cd0810..8161269fa 100644
--- a/src/qemu/qemu_conf.h
+++ b/src/qemu/qemu_conf.h
@@ -135,6 +135,9 @@ struct qemud_driver {
      * of guests which will be automatically killed
      * when the virConnectPtr is closed*/
     virHashTablePtr autodestroy;
+
+    int keepAliveInterval;
+    unsigned int keepAliveCount;
 };
 
 typedef struct _qemuDomainCmdlineDef qemuDomainCmdlineDef;
diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 3b50fc6ea..ee9a84e3a 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -2222,6 +2222,10 @@ static int doPeer2PeerMigrate(struct qemud_driver *driver,
         return -1;
     }
 
+    if (virConnectSetKeepAlive(dconn, driver->keepAliveInterval,
+                               driver->keepAliveCount) < 0)
+        goto cleanup;
+
     qemuDomainObjEnterRemoteWithDriver(driver, vm);
     p2p = VIR_DRV_SUPPORTS_FEATURE(dconn->driver, dconn,
                                    VIR_DRV_FEATURE_MIGRATION_P2P);
diff --git a/src/qemu/test_libvirtd_qemu.aug b/src/qemu/test_libvirtd_qemu.aug
index b1f91143d..f7476ae5d 100644
--- a/src/qemu/test_libvirtd_qemu.aug
+++ b/src/qemu/test_libvirtd_qemu.aug
@@ -115,6 +115,9 @@ vnc_auto_unix_socket = 1
 max_processes = 12345
 
 lock_manager = \"fcntl\"
+
+keepalive_interval = 1
+keepalive_count = 42
 "
 
    test Libvirtd_qemu.lns get conf =
@@ -240,3 +243,6 @@ lock_manager = \"fcntl\"
 { "max_processes" = "12345" }
 { "#empty" }
 { "lock_manager" = "fcntl" }
+{ "#empty" }
+{ "keepalive_interval" = "1" }
+{ "keepalive_count" = "42" }
-- 
2.39.5