Re: [Qemu-devel] [Qemu-block] [PATCH v2 4/7] curl: Pass CURLSocket to curl_multi_do()

[Maxim Levitsky <mlevitsk@redhat.com>]

On Tue, 2019-09-10 at 14:41 +0200, Max Reitz wrote:
> curl_multi_do_locked() currently marks all sockets as ready.  That is
> not only inefficient, but in fact unsafe (the loop is).  A follow-up
> patch will change that, but to do so, curl_multi_do_locked() needs to
> know exactly which socket is ready; and that is accomplished by this
> patch here.
> 
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  block/curl.c | 20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
> 
> diff --git a/block/curl.c b/block/curl.c
> index 5838afef99..cf2686218d 100644
> --- a/block/curl.c
> +++ b/block/curl.c
> @@ -185,15 +185,15 @@ static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
>      switch (action) {
>          case CURL_POLL_IN:
>              aio_set_fd_handler(s->aio_context, fd, false,
> -                               curl_multi_do, NULL, NULL, state);
> +                               curl_multi_do, NULL, NULL, socket);
>              break;
>          case CURL_POLL_OUT:
>              aio_set_fd_handler(s->aio_context, fd, false,
> -                               NULL, curl_multi_do, NULL, state);
> +                               NULL, curl_multi_do, NULL, socket);
>              break;
>          case CURL_POLL_INOUT:
>              aio_set_fd_handler(s->aio_context, fd, false,
> -                               curl_multi_do, curl_multi_do, NULL, state);
> +                               curl_multi_do, curl_multi_do, NULL, socket);
>              break;
>          case CURL_POLL_REMOVE:
>              aio_set_fd_handler(s->aio_context, fd, false,
> @@ -392,9 +392,10 @@ static void curl_multi_check_completion(BDRVCURLState *s)
>  }
>  
>  /* Called with s->mutex held.  */
> -static void curl_multi_do_locked(CURLState *s)
> +static void curl_multi_do_locked(CURLSocket *ready_socket)
>  {
>      CURLSocket *socket, *next_socket;
> +    CURLState *s = ready_socket->state;
>      int running;
>      int r;
>  
> @@ -413,12 +414,13 @@ static void curl_multi_do_locked(CURLState *s)
>  
>  static void curl_multi_do(void *arg)
>  {
> -    CURLState *s = (CURLState *)arg;
> +    CURLSocket *socket = arg;
> +    BDRVCURLState *s = socket->state->s;
>  
> -    qemu_mutex_lock(&s->s->mutex);
> -    curl_multi_do_locked(s);
> -    curl_multi_check_completion(s->s);
> -    qemu_mutex_unlock(&s->s->mutex);
> +    qemu_mutex_lock(&s->mutex);
> +    curl_multi_do_locked(socket);
> +    curl_multi_check_completion(s);
> +    qemu_mutex_unlock(&s->mutex);
>  }
>  
>  static void curl_multi_timeout_do(void *arg)

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Best regards,
	Maxim Levitsky