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 4:49 PM Hailiang Zhang <
address@hidden> wrote:

> Hi,
>
> On 2017/2/16 18:40, Marc-André Lureau wrote:
> > 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.
> >
>
> In that case, i have to modify all the places call this helper,
> About eleven places in six files，is it acceptable ？
>

Yes, that's fine.

>
> Thanks.
>
> >   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