Re: [Qemu-devel] [PATCH] qtest: ask endianness of the target in qtest_init()

[Greg Kurz <groug@kaod.org>]

On Thu,  6 Oct 2016 20:56:58 +0200
Laurent Vivier <lvivier@redhat.com> wrote:

> The target endianness is not deduced anymore from
> the architecture name but asked directly to the guest,
> using a new qtest command: "endianness". As it can't
> change (this is the value of TARGET_WORDS_BIGENDIAN),
> we store it to not have to ask every time we want to
> know if we have to byte-swap a value.
> 
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> CC: Greg Kurz <groug@kaod.org>
> CC: David Gibson <david@gibson.dropbear.id.au>
> CC: Peter Maydell <peter.maydell@linaro.org>
> ---
> Note: this patch can be seen as a v2 of
> "qtest: evaluate endianness of the target in qtest_init()"
> from the patch series "tests: enable virtio tests on SPAPR"
> in which I have added the idea from Peter to ask the endianness
> directly to the guest using a new qtest command.
> 

This is definitely an improvement indeed.

Reviewed-by: Greg Kurz <groug@kaod.org>

>  qtest.c                   |   7 ++
>  tests/libqos/virtio-pci.c |   2 +-
>  tests/libqtest.c          | 224 ++++++++++++++++++++--------------------------
>  tests/libqtest.h          |  16 +++-
>  tests/virtio-blk-test.c   |   2 +-
>  5 files changed, 118 insertions(+), 133 deletions(-)
> 
> diff --git a/qtest.c b/qtest.c
> index 22482cc..b53b39c 100644
> --- a/qtest.c
> +++ b/qtest.c
> @@ -537,6 +537,13 @@ static void qtest_process_command(CharDriverState *chr, gchar **words)
>  
>          qtest_send_prefix(chr);
>          qtest_send(chr, "OK\n");
> +    } else if (strcmp(words[0], "endianness") == 0) {
> +        qtest_send_prefix(chr);
> +#if defined(TARGET_WORDS_BIGENDIAN)
> +        qtest_sendf(chr, "OK big\n");
> +#else
> +        qtest_sendf(chr, "OK little\n");
> +#endif
>  #ifdef TARGET_PPC64
>      } else if (strcmp(words[0], "rtas") == 0) {
>          uint64_t res, args, ret;
> diff --git a/tests/libqos/virtio-pci.c b/tests/libqos/virtio-pci.c
> index 18b92b9..6e005c1 100644
> --- a/tests/libqos/virtio-pci.c
> +++ b/tests/libqos/virtio-pci.c
> @@ -86,7 +86,7 @@ static uint64_t qvirtio_pci_config_readq(QVirtioDevice *d, uint64_t addr)
>      int i;
>      uint64_t u64 = 0;
>  
> -    if (qtest_big_endian()) {
> +    if (target_big_endian()) {
>          for (i = 0; i < 8; ++i) {
>              u64 |= (uint64_t)qpci_io_readb(dev->pdev,
>                                  (void *)(uintptr_t)addr + i) << (7 - i) * 8;
> diff --git a/tests/libqtest.c b/tests/libqtest.c
> index 6f6bdf1..27cf6b1 100644
> --- a/tests/libqtest.c
> +++ b/tests/libqtest.c
> @@ -37,6 +37,7 @@ struct QTestState
>      bool irq_level[MAX_IRQ];
>      GString *rx;
>      pid_t qemu_pid;  /* our child QEMU process */
> +    bool big_endian;
>  };
>  
>  static GHookList abrt_hooks;
> @@ -146,89 +147,6 @@ void qtest_add_abrt_handler(GHookFunc fn, const void *data)
>      g_hook_prepend(&abrt_hooks, hook);
>  }
>  
> -QTestState *qtest_init(const char *extra_args)
> -{
> -    QTestState *s;
> -    int sock, qmpsock, i;
> -    gchar *socket_path;
> -    gchar *qmp_socket_path;
> -    gchar *command;
> -    const char *qemu_binary;
> -
> -    qemu_binary = getenv("QTEST_QEMU_BINARY");
> -    g_assert(qemu_binary != NULL);
> -
> -    s = g_malloc(sizeof(*s));
> -
> -    socket_path = g_strdup_printf("/tmp/qtest-%d.sock", getpid());
> -    qmp_socket_path = g_strdup_printf("/tmp/qtest-%d.qmp", getpid());
> -
> -    sock = init_socket(socket_path);
> -    qmpsock = init_socket(qmp_socket_path);
> -
> -    qtest_add_abrt_handler(kill_qemu_hook_func, s);
> -
> -    s->qemu_pid = fork();
> -    if (s->qemu_pid == 0) {
> -        setenv("QEMU_AUDIO_DRV", "none", true);
> -        command = g_strdup_printf("exec %s "
> -                                  "-qtest unix:%s,nowait "
> -                                  "-qtest-log %s "
> -                                  "-qmp unix:%s,nowait "
> -                                  "-machine accel=qtest "
> -                                  "-display none "
> -                                  "%s", qemu_binary, socket_path,
> -                                  getenv("QTEST_LOG") ? "/dev/fd/2" : "/dev/null",
> -                                  qmp_socket_path,
> -                                  extra_args ?: "");
> -        execlp("/bin/sh", "sh", "-c", command, NULL);
> -        exit(1);
> -    }
> -
> -    s->fd = socket_accept(sock);
> -    if (s->fd >= 0) {
> -        s->qmp_fd = socket_accept(qmpsock);
> -    }
> -    unlink(socket_path);
> -    unlink(qmp_socket_path);
> -    g_free(socket_path);
> -    g_free(qmp_socket_path);
> -
> -    g_assert(s->fd >= 0 && s->qmp_fd >= 0);
> -
> -    s->rx = g_string_new("");
> -    for (i = 0; i < MAX_IRQ; i++) {
> -        s->irq_level[i] = false;
> -    }
> -
> -    /* Read the QMP greeting and then do the handshake */
> -    qtest_qmp_discard_response(s, "");
> -    qtest_qmp_discard_response(s, "{ 'execute': 'qmp_capabilities' }");
> -
> -    if (getenv("QTEST_STOP")) {
> -        kill(s->qemu_pid, SIGSTOP);
> -    }
> -
> -    return s;
> -}
> -
> -void qtest_quit(QTestState *s)
> -{
> -    qtest_instances = g_list_remove(qtest_instances, s);
> -    g_hook_destroy_link(&abrt_hooks, g_hook_find_data(&abrt_hooks, TRUE, s));
> -
> -    /* Uninstall SIGABRT handler on last instance */
> -    if (!qtest_instances) {
> -        cleanup_sigabrt_handler();
> -    }
> -
> -    kill_qemu(s);
> -    close(s->fd);
> -    close(s->qmp_fd);
> -    g_string_free(s->rx, true);
> -    g_free(s);
> -}
> -
>  static void socket_send(int fd, const char *buf, size_t size)
>  {
>      size_t offset;
> @@ -347,6 +265,99 @@ typedef struct {
>      QDict *response;
>  } QMPResponseParser;
>  
> +QTestState *qtest_init(const char *extra_args)
> +{
> +    QTestState *s;
> +    int sock, qmpsock, i;
> +    gchar *socket_path;
> +    gchar *qmp_socket_path;
> +    gchar *command;
> +    const char *qemu_binary;
> +    gchar **args;
> +
> +    qemu_binary = getenv("QTEST_QEMU_BINARY");
> +    g_assert(qemu_binary != NULL);
> +
> +    s = g_malloc(sizeof(*s));
> +
> +    socket_path = g_strdup_printf("/tmp/qtest-%d.sock", getpid());
> +    qmp_socket_path = g_strdup_printf("/tmp/qtest-%d.qmp", getpid());
> +
> +    sock = init_socket(socket_path);
> +    qmpsock = init_socket(qmp_socket_path);
> +
> +    qtest_add_abrt_handler(kill_qemu_hook_func, s);
> +
> +    s->qemu_pid = fork();
> +    if (s->qemu_pid == 0) {
> +        setenv("QEMU_AUDIO_DRV", "none", true);
> +        command = g_strdup_printf("exec %s "
> +                                  "-qtest unix:%s,nowait "
> +                                  "-qtest-log %s "
> +                                  "-qmp unix:%s,nowait "
> +                                  "-machine accel=qtest "
> +                                  "-display none "
> +                                  "%s", qemu_binary, socket_path,
> +                                  getenv("QTEST_LOG") ? "/dev/fd/2"
> +                                                      : "/dev/null",
> +                                  qmp_socket_path,
> +                                  extra_args ?: "");
> +        execlp("/bin/sh", "sh", "-c", command, NULL);
> +        exit(1);
> +    }
> +
> +    s->fd = socket_accept(sock);
> +    if (s->fd >= 0) {
> +        s->qmp_fd = socket_accept(qmpsock);
> +    }
> +    unlink(socket_path);
> +    unlink(qmp_socket_path);
> +    g_free(socket_path);
> +    g_free(qmp_socket_path);
> +
> +    g_assert(s->fd >= 0 && s->qmp_fd >= 0);
> +
> +    s->rx = g_string_new("");
> +    for (i = 0; i < MAX_IRQ; i++) {
> +        s->irq_level[i] = false;
> +    }
> +
> +    /* Read the QMP greeting and then do the handshake */
> +    qtest_qmp_discard_response(s, "");
> +    qtest_qmp_discard_response(s, "{ 'execute': 'qmp_capabilities' }");
> +
> +    if (getenv("QTEST_STOP")) {
> +        kill(s->qemu_pid, SIGSTOP);
> +    }
> +
> +    /* ask endianness of the target */
> +
> +    qtest_sendf(s, "endianness\n");
> +    args = qtest_rsp(s, 1);
> +    g_assert(strcmp(args[1], "big") == 0 || strcmp(args[1], "little") == 0);
> +    s->big_endian = strcmp(args[1], "big") == 0;
> +    g_strfreev(args);
> +
> +    return s;
> +}
> +
> +void qtest_quit(QTestState *s)
> +{
> +    qtest_instances = g_list_remove(qtest_instances, s);
> +    g_hook_destroy_link(&abrt_hooks, g_hook_find_data(&abrt_hooks, TRUE, s));
> +
> +    /* Uninstall SIGABRT handler on last instance */
> +    if (!qtest_instances) {
> +        cleanup_sigabrt_handler();
> +    }
> +
> +    kill_qemu(s);
> +    close(s->fd);
> +    close(s->qmp_fd);
> +    g_string_free(s->rx, true);
> +    g_free(s);
> +}
> +
>  static void qmp_response(JSONMessageParser *parser, GQueue *tokens)
>  {
>      QMPResponseParser *qmp = container_of(parser, QMPResponseParser, parser);
> @@ -886,50 +897,7 @@ char *hmp(const char *fmt, ...)
>      return ret;
>  }
>  
> -bool qtest_big_endian(void)
> +bool qtest_big_endian(QTestState *s)
>  {
> -    const char *arch = qtest_get_arch();
> -    int i;
> -
> -    static const struct {
> -        const char *arch;
> -        bool big_endian;
> -    } endianness[] = {
> -        { "aarch64", false },
> -        { "alpha", false },
> -        { "arm", false },
> -        { "cris", false },
> -        { "i386", false },
> -        { "lm32", true },
> -        { "m68k", true },
> -        { "microblaze", true },
> -        { "microblazeel", false },
> -        { "mips", true },
> -        { "mips64", true },
> -        { "mips64el", false },
> -        { "mipsel", false },
> -        { "moxie", true },
> -        { "or32", true },
> -        { "ppc", true },
> -        { "ppc64", true },
> -        { "ppcemb", true },
> -        { "s390x", true },
> -        { "sh4", false },
> -        { "sh4eb", true },
> -        { "sparc", true },
> -        { "sparc64", true },
> -        { "unicore32", false },
> -        { "x86_64", false },
> -        { "xtensa", false },
> -        { "xtensaeb", true },
> -        {},
> -    };
> -
> -    for (i = 0; endianness[i].arch; i++) {
> -        if (strcmp(endianness[i].arch, arch) == 0) {
> -            return endianness[i].big_endian;
> -        }
> -    }
> -
> -    return false;
> +    return s->big_endian;
>  }
> diff --git a/tests/libqtest.h b/tests/libqtest.h
> index f7402e0..4be1f77 100644
> --- a/tests/libqtest.h
> +++ b/tests/libqtest.h
> @@ -410,6 +410,14 @@ int64_t qtest_clock_step(QTestState *s, int64_t step);
>  int64_t qtest_clock_set(QTestState *s, int64_t val);
>  
>  /**
> + * qtest_big_endian:
> + * @s: QTestState instance to operate on.
> + *
> + * Returns: True if the architecture under test has a big endian configuration.
> + */
> +bool qtest_big_endian(QTestState *s);
> +
> +/**
>   * qtest_get_arch:
>   *
>   * Returns: The architecture for the QEMU executable under test.
> @@ -874,12 +882,14 @@ static inline int64_t clock_set(int64_t val)
>  }
>  
>  /**
> - * qtest_big_endian:
> + * target_big_endian:
>   *
>   * Returns: True if the architecture under test has a big endian configuration.
>   */
> -bool qtest_big_endian(void);
> -
> +static inline bool target_big_endian(void)
> +{
> +    return qtest_big_endian(global_qtest);
> +}
>  
>  QDict *qmp_fd_receive(int fd);
>  void qmp_fd_sendv(int fd, const char *fmt, va_list ap);
> diff --git a/tests/virtio-blk-test.c b/tests/virtio-blk-test.c
> index 3c4fecc..0506917 100644
> --- a/tests/virtio-blk-test.c
> +++ b/tests/virtio-blk-test.c
> @@ -125,7 +125,7 @@ static inline void virtio_blk_fix_request(QVirtioBlkReq *req)
>      bool host_endian = false;
>  #endif
>  
> -    if (qtest_big_endian() != host_endian) {
> +    if (target_big_endian() != host_endian) {
>          req->type = bswap32(req->type);
>          req->ioprio = bswap32(req->ioprio);
>          req->sector = bswap64(req->sector);