Re: [Qemu-devel] [PATCH v2 3/4] char: remove the right fd been watched in qemu_chr_fe_set_handlers()

[Marc-André Lureau]

Hi

On Thu, Feb 16, 2017 at 10:08 AM zhanghailiang <
address@hidden> wrote:

> We can call qemu_chr_fe_set_handlers() to add/remove fd been watched
> in 'context' which can be either default main context or other explicit
> context. But the original logic is not correct, we didn't remove
> the right fd because we call g_main_context_find_source_by_id(NULL, tag)
> which always try to find the Gsource from default context.
>
> Fix it by passing the right context to g_main_context_find_source_by_id().
>
> Cc: Paolo Bonzini <address@hidden>
> Cc: Marc-André Lureau <address@hidden>
> Signed-off-by: zhanghailiang <address@hidden>
> ---
>  chardev/char-io.c | 13 +++++++++----
>  chardev/char-io.h |  2 ++
>  chardev/char.c    |  2 +-
>  3 files changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/chardev/char-io.c b/chardev/char-io.c
> index 7dfc3f2..a69cc61 100644
> --- a/chardev/char-io.c
> +++ b/chardev/char-io.c
> @@ -127,14 +127,14 @@ guint io_add_watch_poll(Chardev *chr,
>      return tag;
>  }
>
> -static void io_remove_watch_poll(guint tag)
> +static void io_remove_watch_poll(guint tag, GMainContext *context)
>  {
>      GSource *source;
>      IOWatchPoll *iwp;
>
>      g_return_if_fail(tag > 0);
>
> -    source = g_main_context_find_source_by_id(NULL, tag);
> +    source = g_main_context_find_source_by_id(context, tag);
>      g_return_if_fail(source != NULL);
>
>      iwp = io_watch_poll_from_source(source);
> @@ -146,14 +146,19 @@ static void io_remove_watch_poll(guint tag)
>      g_source_destroy(&iwp->parent);
>  }
>
> -void remove_fd_in_watch(Chardev *chr)
> +void qemu_remove_fd_in_watch(Chardev *chr, GMainContext *context)
>  {
>      if (chr->fd_in_tag) {
> -        io_remove_watch_poll(chr->fd_in_tag);
> +        io_remove_watch_poll(chr->fd_in_tag, context);
>          chr->fd_in_tag = 0;
>      }
>  }
>
> +void remove_fd_in_watch(Chardev *chr)
> +{
> +    qemu_remove_fd_in_watch(chr, NULL);
> +}
> +
>

I would just change the signature of remove_fd_in_watch() instead of
introducing a function.

 int io_channel_send_full(QIOChannel *ioc,
>                           const void *buf, size_t len,
>                           int *fds, size_t nfds)
> diff --git a/chardev/char-io.h b/chardev/char-io.h
> index d7ae5f1..117c888 100644
> --- a/chardev/char-io.h
> +++ b/chardev/char-io.h
> @@ -38,6 +38,8 @@ guint io_add_watch_poll(Chardev *chr,
>
>  void remove_fd_in_watch(Chardev *chr);
>
> +void qemu_remove_fd_in_watch(Chardev *chr, GMainContext *context);
> +
>  int io_channel_send(QIOChannel *ioc, const void *buf, size_t len);
>
>  int io_channel_send_full(QIOChannel *ioc, const void *buf, size_t len,
> diff --git a/chardev/char.c b/chardev/char.c
> index abd525f..5563375 100644
> --- a/chardev/char.c
> +++ b/chardev/char.c
> @@ -560,7 +560,7 @@ void qemu_chr_fe_set_handlers(CharBackend *b,
>      cc = CHARDEV_GET_CLASS(s);
>      if (!opaque && !fd_can_read && !fd_read && !fd_event) {
>          fe_open = 0;
> -        remove_fd_in_watch(s);
> +        qemu_remove_fd_in_watch(s, context);
>      } else {
>          fe_open = 1;
>      }
> --
> 1.8.3.1
>
>
>
otherwise, looks good to me

-- 
Marc-André Lureau