Re: [PULL 11/38] tests/qtest: migration-test: Add tests for file-based migration

[Fabiano Rosas]

Juan Quintela <quintela@redhat.com> writes:

> From: Fabiano Rosas <farosas@suse.de>
>
> Add basic tests for file-based migration.
>
> Note that we cannot use test_precopy_common because that routine
> expects it to be possible to run the migration live. With the file
> transport there is no live migration because we must wait for the
> source to finish writing the migration data to the file before the
> destination can start reading. Add a new migration function
> specifically to handle the file migration.
>
> Reviewed-by: Peter Xu <peterx@redhat.com>
> Reviewed-by: Juan Quintela <quintela@redhat.com>
> Signed-off-by: Fabiano Rosas <farosas@suse.de>
> Signed-off-by: Juan Quintela <quintela@redhat.com>
> Message-ID: <20230712190742.22294-7-farosas@suse.de>
> ---
>  tests/qtest/migration-test.c | 147 +++++++++++++++++++++++++++++++++++
>  1 file changed, 147 insertions(+)
>
> diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
> index cef5081f8c..da02b6d692 100644
> --- a/tests/qtest/migration-test.c
> +++ b/tests/qtest/migration-test.c
> @@ -68,6 +68,10 @@ static bool got_dst_resume;
>  
>  #define ANALYZE_SCRIPT "scripts/analyze-migration.py"
>  
> +#define QEMU_VM_FILE_MAGIC 0x5145564d
> +#define FILE_TEST_FILENAME "migfile"
> +#define FILE_TEST_OFFSET 0x1000
> +
>  #if defined(__linux__)
>  #include <sys/syscall.h>
>  #include <sys/vfs.h>
> @@ -884,6 +888,7 @@ static void test_migrate_end(QTestState *from, QTestState 
> *to, bool test_dest)
>      cleanup("migsocket");
>      cleanup("src_serial");
>      cleanup("dest_serial");
> +    cleanup(FILE_TEST_FILENAME);
>  }
>  
>  #ifdef CONFIG_GNUTLS
> @@ -1667,6 +1672,70 @@ finish:
>      test_migrate_end(from, to, args->result == MIG_TEST_SUCCEED);
>  }
>  
> +static void test_file_common(MigrateCommon *args, bool stop_src)
> +{
> +    QTestState *from, *to;
> +    void *data_hook = NULL;
> +    g_autofree char *connect_uri = g_strdup(args->connect_uri);
> +
> +    if (test_migrate_start(&from, &to, args->listen_uri, &args->start)) {
> +        return;
> +    }
> +
> +    /*
> +     * File migration is never live. We can keep the source VM running
> +     * during migration, but the destination will not be running
> +     * concurrently.
> +     */
> +    g_assert_false(args->live);
> +
> +    if (args->start_hook) {
> +        data_hook = args->start_hook(from, to);
> +    }
> +
> +    migrate_ensure_converge(from);
> +    wait_for_serial("src_serial");
> +
> +    if (stop_src) {
> +        qtest_qmp_assert_success(from, "{ 'execute' : 'stop'}");
> +        if (!got_src_stop) {
> +            qtest_qmp_eventwait(from, "STOP");
> +        }
> +    }
> +
> +    if (args->result == MIG_TEST_QMP_ERROR) {
> +        migrate_qmp_fail(from, connect_uri, "{}");
> +        goto finish;
> +    }
> +
> +    migrate_qmp(from, connect_uri, "{}");
> +    wait_for_migration_complete(from);
> +
> +    /*
> +     * We need to wait for the source to finish before starting the
> +     * destination.
> +     */
> +    migrate_incoming_qmp(to, connect_uri, "{}");
> +    wait_for_migration_complete(to);
> +
> +    if (stop_src) {
> +        qtest_qmp_assert_success(to, "{ 'execute' : 'cont'}");
> +    }
> +
> +    if (!got_dst_resume) {
> +        qtest_qmp_eventwait(to, "RESUME");
> +    }
> +
> +    wait_for_serial("dest_serial");
> +
> +finish:
> +    if (args->finish_hook) {
> +        args->finish_hook(from, to, data_hook);
> +    }
> +
> +    test_migrate_end(from, to, args->result == MIG_TEST_SUCCEED);
> +}
> +
>  static void test_precopy_unix_plain(void)
>  {
>      g_autofree char *uri = g_strdup_printf("unix:%s/migsocket", tmpfs);
> @@ -1862,6 +1931,76 @@ static void test_precopy_unix_compress_nowait(void)
>      test_precopy_common(&args);
>  }
>  
> +static void test_precopy_file(void)
> +{
> +    g_autofree char *uri = g_strdup_printf("file:%s/%s", tmpfs,
> +                                           FILE_TEST_FILENAME);
> +    MigrateCommon args = {
> +        .connect_uri = uri,
> +        .listen_uri = "defer",
> +    };
> +
> +    test_file_common(&args, true);
> +}
> +
> +static void file_offset_finish_hook(QTestState *from, QTestState *to,
> +                                    void *opaque)
> +{
> +#if defined(__linux__)
> +    g_autofree char *path = g_strdup_printf("%s/%s", tmpfs, 
> FILE_TEST_FILENAME);
> +    size_t size = FILE_TEST_OFFSET + sizeof(QEMU_VM_FILE_MAGIC);
> +    uintptr_t *addr, *p;
> +    int fd;
> +
> +    fd = open(path, O_RDONLY);
> +    g_assert(fd != -1);
> +    addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0);
> +    g_assert(addr != MAP_FAILED);
> +
> +    /*
> +     * Ensure the skipped offset contains zeros and the migration
> +     * stream starts at the right place.
> +     */
> +    p = addr;
> +    while (p < addr + FILE_TEST_OFFSET / sizeof(uintptr_t)) {
> +        g_assert(*p == 0);
> +        p++;
> +    }
> +    g_assert_cmpint(cpu_to_be32(*p), ==, QEMU_VM_FILE_MAGIC);

This truncates to 32-bits, so it breaks on a BE host. We need this:

-->8--
>From ea0c2d1c988add48d9754891a9fc7f6854a9718a Mon Sep 17 00:00:00 2001
From: Fabiano Rosas <farosas@suse.de>
Date: Mon, 16 Oct 2023 15:21:49 -0300
Subject: [PATCH] fixup! tests/qtest: migration-test: Add tests for file-based
 migration

---
 tests/qtest/migration-test.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/qtest/migration-test.c b/tests/qtest/migration-test.c
index da02b6d692..e1c110537b 100644
--- a/tests/qtest/migration-test.c
+++ b/tests/qtest/migration-test.c
@@ -1966,7 +1966,7 @@ static void file_offset_finish_hook(QTestState *from, 
QTestState *to,
         g_assert(*p == 0);
         p++;
     }
-    g_assert_cmpint(cpu_to_be32(*p), ==, QEMU_VM_FILE_MAGIC);
+    g_assert_cmpint(cpu_to_be64(*p) >> 32, ==, QEMU_VM_FILE_MAGIC);
 
     munmap(addr, size);
     close(fd);
-- 
2.35.3