[PULL 13/22] tests/qtest/migration: Isolate test initialization

[Fabiano Rosas]

We currently have some environment validation to perform and flags to
set during the initialization of the tests. To be able to add more
migration test binaries, we'll need these tasks to be in their own
function so they can be called from more than one place.

Move the initialization code to a function and introduce the
MigrationTestEnv structure to hold the flags that are accessed during
test registration.

Make the env object static to avoid have to change all the code to
pass it around. Similarly with the tmpfs variable, which is used
extensively.

Note: I'm keeping the new functions in migration-test.c because they
are going to be moved in the next patch to the correct place.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
---
 tests/qtest/migration-test.c | 122 ++++++++++++++++++++++++-----------
 1 file changed, 86 insertions(+), 36 deletions(-)

diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index ab7cbb8251..5617445e6f 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -34,7 +34,6 @@
 
 unsigned start_address;
 unsigned end_address;
-static bool uffd_feature_thread_id;
 static QTestMigrationState src_state;
 static QTestMigrationState dst_state;
 
@@ -86,6 +85,22 @@ typedef enum PostcopyRecoveryFailStage {
 static char *tmpfs;
 static char *bootpath;
 
+typedef struct MigrationTestEnv {
+    bool has_kvm;
+    bool has_tcg;
+    bool has_uffd;
+    bool uffd_feature_thread_id;
+    bool has_dirty_ring;
+    bool is_x86;
+    const char *arch;
+    const char *qemu_src;
+    const char *qemu_dst;
+    char *tmpfs;
+} MigrationTestEnv;
+
+
+MigrationTestEnv *migration_get_env(void);
+
 /*
  * Wait for some output in the serial output file,
  * we get an 'A' followed by an endless string of 'B's
@@ -972,6 +987,8 @@ static int migrate_postcopy_prepare(QTestState **from_ptr,
 static void migrate_postcopy_complete(QTestState *from, QTestState *to,
                                       MigrateCommon *args)
 {
+    MigrationTestEnv *env = migration_get_env();
+
     wait_for_migration_complete(from);
 
     if (args->start.suspend_me) {
@@ -982,7 +999,7 @@ static void migrate_postcopy_complete(QTestState *from, 
QTestState *to,
     /* Make sure we get at least one "B" on destination */
     wait_for_serial("dest_serial");
 
-    if (uffd_feature_thread_id) {
+    if (env->uffd_feature_thread_id) {
         read_blocktime(to);
     }
 
@@ -3429,63 +3446,99 @@ static void test_dirty_limit(void)
     migrate_end(from, to, true);
 }
 
-int main(int argc, char **argv)
+MigrationTestEnv *migration_get_env(void)
 {
-    bool has_kvm, has_tcg;
-    bool has_uffd, is_x86;
-    const char *arch;
+    static MigrationTestEnv *env;
     g_autoptr(GError) err = NULL;
-    const char *qemu_src = getenv(QEMU_ENV_SRC);
-    const char *qemu_dst = getenv(QEMU_ENV_DST);
-    int ret;
 
-    g_test_init(&argc, &argv, NULL);
+    if (env) {
+        return env;
+    }
+
+    env = g_new0(MigrationTestEnv, 1);
+    env->qemu_src = getenv(QEMU_ENV_SRC);
+    env->qemu_dst = getenv(QEMU_ENV_DST);
 
     /*
      * The default QTEST_QEMU_BINARY must always be provided because
      * that is what helpers use to query the accel type and
      * architecture.
      */
-    if (qemu_src && qemu_dst) {
+    if (env->qemu_src && env->qemu_dst) {
         g_test_message("Only one of %s, %s is allowed",
                        QEMU_ENV_SRC, QEMU_ENV_DST);
         exit(1);
     }
 
-    has_kvm = qtest_has_accel("kvm");
-    has_tcg = qtest_has_accel("tcg");
+    env->has_kvm = qtest_has_accel("kvm");
+    env->has_tcg = qtest_has_accel("tcg");
 
-    if (!has_tcg && !has_kvm) {
+    if (!env->has_tcg && !env->has_kvm) {
         g_test_skip("No KVM or TCG accelerator available");
-        return 0;
+        return env;
     }
 
-    has_uffd = ufd_version_check(&uffd_feature_thread_id);
-    arch = qtest_get_arch();
-    is_x86 = !strcmp(arch, "i386") || !strcmp(arch, "x86_64");
+    env->has_dirty_ring = kvm_dirty_ring_supported();
+    env->has_uffd = ufd_version_check(&env->uffd_feature_thread_id);
+    env->arch = qtest_get_arch();
+    env->is_x86 = !strcmp(env->arch, "i386") || !strcmp(env->arch, "x86_64");
 
-    tmpfs = g_dir_make_tmp("migration-test-XXXXXX", &err);
-    if (!tmpfs) {
+    env->tmpfs = g_dir_make_tmp("migration-test-XXXXXX", &err);
+    if (!env->tmpfs) {
         g_test_message("Can't create temporary directory in %s: %s",
                        g_get_tmp_dir(), err->message);
     }
-    g_assert(tmpfs);
+    g_assert(env->tmpfs);
 
+    return env;
+}
+
+static int migration_env_clean(MigrationTestEnv *env)
+{
+    char *tmpfs;
+    int ret = 0;
+
+    if (!env) {
+        return ret;
+    }
+
+    bootfile_delete();
+
+    tmpfs = env->tmpfs;
+    ret = rmdir(tmpfs);
+    if (ret != 0) {
+        g_test_message("unable to rmdir: path (%s): %s",
+                       tmpfs, strerror(errno));
+    }
+    g_free(tmpfs);
+
+    return ret;
+}
+
+int main(int argc, char **argv)
+{
+    MigrationTestEnv *env;
+    int ret;
+
+    g_test_init(&argc, &argv, NULL);
+    env = migration_get_env();
     module_call_init(MODULE_INIT_QOM);
 
+    tmpfs = env->tmpfs;
+
     migration_test_add("/migration/bad_dest", test_baddest);
 #ifndef _WIN32
     migration_test_add("/migration/analyze-script", test_analyze_script);
 #endif
 
-    if (is_x86) {
+    if (env->is_x86) {
         migration_test_add("/migration/precopy/unix/suspend/live",
                            test_precopy_unix_suspend_live);
         migration_test_add("/migration/precopy/unix/suspend/notlive",
                            test_precopy_unix_suspend_notlive);
     }
 
-    if (has_uffd) {
+    if (env->has_uffd) {
         migration_test_add("/migration/postcopy/plain", test_postcopy);
         migration_test_add("/migration/postcopy/recovery/plain",
                            test_postcopy_recovery);
@@ -3497,7 +3550,7 @@ int main(int argc, char **argv)
                            test_postcopy_recovery_fail_handshake);
         
migration_test_add("/migration/postcopy/recovery/double-failures/reconnect",
                            test_postcopy_recovery_fail_reconnect);
-        if (is_x86) {
+        if (env->is_x86) {
             migration_test_add("/migration/postcopy/suspend",
                                test_postcopy_suspend);
         }
@@ -3552,7 +3605,7 @@ int main(int argc, char **argv)
     migration_test_add("/migration/precopy/unix/tls/psk",
                        test_precopy_unix_tls_psk);
 
-    if (has_uffd) {
+    if (env->has_uffd) {
         /*
          * NOTE: psk test is enough for postcopy, as other types of TLS
          * channels are tested under precopy.  Here what we want to test is the
@@ -3627,9 +3680,9 @@ int main(int argc, char **argv)
     if (g_test_slow()) {
         migration_test_add("/migration/auto_converge",
                            test_auto_converge);
-        if (g_str_equal(arch, "x86_64") &&
-            has_kvm && kvm_dirty_ring_supported()) {
-            migration_test_add("/migration/dirty_limit",
+        if (g_str_equal(env->arch, "x86_64") &&
+            env->has_kvm && env->has_dirty_ring) {
+            migration_test_add("/dirty_limit",
                                test_dirty_limit);
         }
     }
@@ -3680,7 +3733,9 @@ int main(int argc, char **argv)
 #endif /* CONFIG_TASN1 */
 #endif /* CONFIG_GNUTLS */
 
-    if (g_str_equal(arch, "x86_64") && has_kvm && kvm_dirty_ring_supported()) {
+    if (g_str_equal(env->arch, "x86_64") &&
+        env->has_kvm && env->has_dirty_ring) {
+
         migration_test_add("/migration/dirty_ring",
                            test_precopy_unix_dirty_ring);
         if (qtest_has_machine("pc") && g_test_slow()) {
@@ -3693,13 +3748,8 @@ int main(int argc, char **argv)
 
     g_assert_cmpint(ret, ==, 0);
 
-    bootfile_delete();
-    ret = rmdir(tmpfs);
-    if (ret != 0) {
-        g_test_message("unable to rmdir: path (%s): %s",
-                       tmpfs, strerror(errno));
-    }
-    g_free(tmpfs);
+    tmpfs = NULL;
+    ret = migration_env_clean(env);
 
     return ret;
 }
-- 
2.35.3