[PATCH 5/7] qemu: Always assume support for QEMU_CAPS_MIGRATION_PARAM_XBZRLE_CACHE_SIZE

[Peter Krempa <pkrempa@xxxxxxxxxx>]

The 'xbzrle-cache-size' parameter was added in qemu-2.11 thus all
supported qemu versions now use the new code path.

Signed-off-by: Peter Krempa <pkrempa@xxxxxxxxxx>
---
 src/qemu/qemu_driver.c           | 56 +++++++++-----------------------
 src/qemu/qemu_migration_params.c | 18 ----------
 2 files changed, 16 insertions(+), 58 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 0a5239e136..75c7a8a6b2 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -13161,10 +13161,8 @@ qemuDomainMigrateGetCompressionCache(virDomainPtr dom,
 {
     virQEMUDriver *driver = dom->conn->privateData;
     virDomainObj *vm;
-    qemuDomainObjPrivate *priv;
     g_autoptr(qemuMigrationParams) migParams = NULL;
     int ret = -1;
-    int rc;

     virCheckFlags(0, -1);

@@ -13180,8 +13178,6 @@ qemuDomainMigrateGetCompressionCache(virDomainPtr dom,
     if (virDomainObjCheckActive(vm) < 0)
         goto endjob;

-    priv = vm->privateData;
-
     if (!qemuMigrationCapsGet(vm, QEMU_MIGRATION_CAP_XBZRLE)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
                        _("Compressed migration is not supported by "
@@ -13189,22 +13185,14 @@ qemuDomainMigrateGetCompressionCache(virDomainPtr dom,
         goto endjob;
     }

-    if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_PARAM_XBZRLE_CACHE_SIZE)) {
-        if (qemuMigrationParamsFetch(driver, vm, VIR_ASYNC_JOB_NONE,
-                                     &migParams) < 0)
-            goto endjob;
+    if (qemuMigrationParamsFetch(driver, vm, VIR_ASYNC_JOB_NONE,
+                                 &migParams) < 0)
+        goto endjob;

-        if (qemuMigrationParamsGetULL(migParams,
-                                      QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE,
-                                      cacheSize) < 0)
-            goto endjob;
-    } else {
-        qemuDomainObjEnterMonitor(driver, vm);
-        rc = qemuMonitorGetMigrationCacheSize(priv->mon, cacheSize);
-        qemuDomainObjExitMonitor(vm);
-        if (rc < 0)
-            goto endjob;
-    }
+    if (qemuMigrationParamsGetULL(migParams,
+                                  QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE,
+                                  cacheSize) < 0)
+        goto endjob;

     ret = 0;

@@ -13223,10 +13211,8 @@ qemuDomainMigrateSetCompressionCache(virDomainPtr dom,
 {
     virQEMUDriver *driver = dom->conn->privateData;
     virDomainObj *vm;
-    qemuDomainObjPrivate *priv;
     g_autoptr(qemuMigrationParams) migParams = NULL;
     int ret = -1;
-    int rc;

     virCheckFlags(0, -1);

@@ -13242,8 +13228,6 @@ qemuDomainMigrateSetCompressionCache(virDomainPtr dom,
     if (virDomainObjCheckActive(vm) < 0)
         goto endjob;

-    priv = vm->privateData;
-
     if (!qemuMigrationCapsGet(vm, QEMU_MIGRATION_CAP_XBZRLE)) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
                        _("Compressed migration is not supported by "
@@ -13252,25 +13236,17 @@ qemuDomainMigrateSetCompressionCache(virDomainPtr dom,
     }

     VIR_DEBUG("Setting compression cache to %llu B", cacheSize);
-    if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_PARAM_XBZRLE_CACHE_SIZE)) {
-        if (!(migParams = qemuMigrationParamsNew()))
-            goto endjob;
+    if (!(migParams = qemuMigrationParamsNew()))
+        goto endjob;

-        if (qemuMigrationParamsSetULL(migParams,
-                                      QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE,
-                                      cacheSize) < 0)
-            goto endjob;
+    if (qemuMigrationParamsSetULL(migParams,
+                                  QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE,
+                                  cacheSize) < 0)
+        goto endjob;

-        if (qemuMigrationParamsApply(driver, vm, VIR_ASYNC_JOB_NONE,
-                                     migParams, 0) < 0)
-            goto endjob;
-    } else {
-        qemuDomainObjEnterMonitor(driver, vm);
-        rc = qemuMonitorSetMigrationCacheSize(priv->mon, cacheSize);
-        qemuDomainObjExitMonitor(vm);
-        if (rc < 0)
-            goto endjob;
-    }
+    if (qemuMigrationParamsApply(driver, vm, VIR_ASYNC_JOB_NONE,
+                                 migParams, 0) < 0)
+        goto endjob;

     ret = 0;

diff --git a/src/qemu/qemu_migration_params.c b/src/qemu/qemu_migration_params.c
index 6ea0bde13a..0bce358ac3 100644
--- a/src/qemu/qemu_migration_params.c
+++ b/src/qemu/qemu_migration_params.c
@@ -886,10 +886,8 @@ qemuMigrationParamsApply(virQEMUDriver *driver,
                          unsigned long apiFlags)
 {
     qemuDomainObjPrivate *priv = vm->privateData;
-    bool xbzrleCacheSize_old = false;
     g_autoptr(virJSONValue) params = NULL;
     g_autoptr(virJSONValue) caps = NULL;
-    qemuMigrationParam xbzrle = QEMU_MIGRATION_PARAM_XBZRLE_CACHE_SIZE;
     bool postcopyResume = !!(apiFlags & VIR_MIGRATE_POSTCOPY_RESUME);
     int ret = -1;

@@ -917,19 +915,6 @@ qemuMigrationParamsApply(virQEMUDriver *driver,
         }
     }

-    /* If QEMU is too old to support xbzrle-cache-size migration parameter,
-     * we need to set it via migrate-set-cache-size and tell
-     * qemuMonitorSetMigrationParams to ignore this parameter.
-     */
-    if (migParams->params[xbzrle].set &&
-        !virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MIGRATION_PARAM_XBZRLE_CACHE_SIZE)) {
-        if (qemuMonitorSetMigrationCacheSize(priv->mon,
-                                             migParams->params[xbzrle].value.ull) < 0)
-            goto cleanup;
-        xbzrleCacheSize_old = true;
-        migParams->params[xbzrle].set = false;
-    }
-
     if (!(params = qemuMigrationParamsToJSON(migParams, postcopyResume)))
         goto cleanup;

@@ -942,9 +927,6 @@ qemuMigrationParamsApply(virQEMUDriver *driver,
  cleanup:
     qemuDomainObjExitMonitor(vm);

-    if (xbzrleCacheSize_old)
-        migParams->params[xbzrle].set = true;
-
     return ret;
 }

-- 
2.36.1