[libvirt] [PATCH v2 18/20] qemu: Send updated CPU in migration cookie

[Jiri Denemark]

Since the domain XML send during migration uses the original guest CPU
definition but we still want the destination to enforce ABI if it is new
enough, we send the live updated CPU definition in a migration cookie.

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
Reviewed-by: Pavel Hrdina <phrdina at redhat.com>
---

Notes:
    Version 2:
    - persistent def related hunk moved to a separate patch

 src/qemu/qemu_migration.c        |  6 +++++-
 src/qemu/qemu_migration_cookie.c | 31 ++++++++++++++++++++++++++++++-
 src/qemu/qemu_migration_cookie.h |  5 +++++
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 40564ac63..134c76c5e 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -2020,6 +2020,9 @@ qemuMigrationBeginPhase(virQEMUDriverPtr driver,
          vm->newDef && !qemuDomainVcpuHotplugIsInOrder(vm->newDef)))
         cookieFlags |= QEMU_MIGRATION_COOKIE_CPU_HOTPLUG;
 
+    if (priv->origCPU)
+        cookieFlags |= QEMU_MIGRATION_COOKIE_CPU;
+
     if (!(mig = qemuMigrationEatCookie(driver, vm, NULL, 0, 0)))
         goto cleanup;
 
@@ -2644,7 +2647,8 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
                                        QEMU_MIGRATION_COOKIE_LOCKSTATE |
                                        QEMU_MIGRATION_COOKIE_NBD |
                                        QEMU_MIGRATION_COOKIE_MEMORY_HOTPLUG |
-                                       QEMU_MIGRATION_COOKIE_CPU_HOTPLUG)))
+                                       QEMU_MIGRATION_COOKIE_CPU_HOTPLUG |
+                                       QEMU_MIGRATION_COOKIE_CPU)))
         goto cleanup;
 
     if (STREQ_NULLABLE(protocol, "rdma") &&
diff --git a/src/qemu/qemu_migration_cookie.c b/src/qemu/qemu_migration_cookie.c
index 559b1f0c1..af0ac0341 100644
--- a/src/qemu/qemu_migration_cookie.c
+++ b/src/qemu/qemu_migration_cookie.c
@@ -48,7 +48,8 @@ VIR_ENUM_IMPL(qemuMigrationCookieFlag,
               "nbd",
               "statistics",
               "memory-hotplug",
-              "cpu-hotplug");
+              "cpu-hotplug",
+              "cpu");
 
 
 static void
@@ -109,6 +110,7 @@ qemuMigrationCookieFree(qemuMigrationCookiePtr mig)
     VIR_FREE(mig->lockState);
     VIR_FREE(mig->lockDriver);
     VIR_FREE(mig->jobInfo);
+    virCPUDefFree(mig->cpu);
     VIR_FREE(mig);
 }
 
@@ -519,6 +521,22 @@ qemuMigrationCookieAddStatistics(qemuMigrationCookiePtr mig,
 }
 
 
+static int
+qemuMigrationCookieAddCPU(qemuMigrationCookiePtr mig,
+                          virDomainObjPtr vm)
+{
+    if (mig->cpu)
+        return 0;
+
+    if (!(mig->cpu = virCPUDefCopy(vm->def->cpu)))
+        return -1;
+
+    mig->flags |= QEMU_MIGRATION_COOKIE_CPU;
+
+    return 0;
+}
+
+
 static void
 qemuMigrationCookieGraphicsXMLFormat(virBufferPtr buf,
                                      qemuMigrationCookieGraphicsPtr grap)
@@ -755,6 +773,9 @@ qemuMigrationCookieXMLFormat(virQEMUDriverPtr driver,
     if (mig->flags & QEMU_MIGRATION_COOKIE_STATS && mig->jobInfo)
         qemuMigrationCookieStatisticsXMLFormat(buf, mig->jobInfo);
 
+    if (mig->flags & QEMU_MIGRATION_COOKIE_CPU && mig->cpu)
+        virCPUDefFormatBufFull(buf, mig->cpu, NULL, false);
+
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</qemu-migration>\n");
     return 0;
@@ -1198,6 +1219,10 @@ qemuMigrationCookieXMLParse(qemuMigrationCookiePtr mig,
         (!(mig->jobInfo = qemuMigrationCookieStatisticsXMLParse(ctxt))))
         goto error;
 
+    if (flags & QEMU_MIGRATION_COOKIE_CPU &&
+        virCPUDefParseXML(ctxt, "./cpu[1]", VIR_CPU_TYPE_GUEST, &mig->cpu) < 0)
+        goto error;
+
     virObjectUnref(caps);
     return 0;
 
@@ -1274,6 +1299,10 @@ qemuMigrationBakeCookie(qemuMigrationCookiePtr mig,
     if (flags & QEMU_MIGRATION_COOKIE_CPU_HOTPLUG)
         mig->flagsMandatory |= QEMU_MIGRATION_COOKIE_CPU_HOTPLUG;
 
+    if (flags & QEMU_MIGRATION_COOKIE_CPU &&
+        qemuMigrationCookieAddCPU(mig, dom) < 0)
+        return -1;
+
     if (!(*cookieout = qemuMigrationCookieXMLFormatStr(driver, mig)))
         return -1;
 
diff --git a/src/qemu/qemu_migration_cookie.h b/src/qemu/qemu_migration_cookie.h
index b009d5bf5..e5f3d75a9 100644
--- a/src/qemu/qemu_migration_cookie.h
+++ b/src/qemu/qemu_migration_cookie.h
@@ -28,6 +28,7 @@ typedef enum {
     QEMU_MIGRATION_COOKIE_FLAG_STATS,
     QEMU_MIGRATION_COOKIE_FLAG_MEMORY_HOTPLUG,
     QEMU_MIGRATION_COOKIE_FLAG_CPU_HOTPLUG,
+    QEMU_MIGRATION_COOKIE_FLAG_CPU,
 
     QEMU_MIGRATION_COOKIE_FLAG_LAST
 } qemuMigrationCookieFlags;
@@ -43,6 +44,7 @@ typedef enum {
     QEMU_MIGRATION_COOKIE_STATS = (1 << QEMU_MIGRATION_COOKIE_FLAG_STATS),
     QEMU_MIGRATION_COOKIE_MEMORY_HOTPLUG = (1 << QEMU_MIGRATION_COOKIE_FLAG_MEMORY_HOTPLUG),
     QEMU_MIGRATION_COOKIE_CPU_HOTPLUG = (1 << QEMU_MIGRATION_COOKIE_FLAG_CPU_HOTPLUG),
+    QEMU_MIGRATION_COOKIE_CPU = (1 << QEMU_MIGRATION_COOKIE_FLAG_CPU),
 } qemuMigrationCookieFeatures;
 
 typedef struct _qemuMigrationCookieGraphics qemuMigrationCookieGraphics;
@@ -122,6 +124,9 @@ struct _qemuMigrationCookie {
 
     /* If (flags & QEMU_MIGRATION_COOKIE_STATS) */
     qemuDomainJobInfoPtr jobInfo;
+
+    /* If flags & QEMU_MIGRATION_COOKIE_CPU */
+    virCPUDefPtr cpu;
 };
 
 
-- 
2.13.0