| Message ID | 20240306081505.2258405-1-armbru@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | char: Slightly better error reporting when chardev is in use | expand |
Hi On Wed, Mar 6, 2024 at 12:15 PM Markus Armbruster <armbru@redhat.com> wrote: > > Both > > $ qemu-system-x86_64 -chardev null,id=chr0,mux=on -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 > > and > > $ qemu-system-x86_64 -chardev null,id=chr0 -mon chardev=chr0 -mon chardev=chr0 > fail with > > qemu-system-x86_64: -mon chardev=chr0: Device 'chr0' is in use > > Improve to > > qemu-system-x86_64: -mon chardev=chr0: too many uses of multiplexed chardev 'chr0' (maximum is 4) > > and > > qemu-system-x86_64: -mon chardev=chr0: chardev 'chr0' is already in use > > Signed-off-by: Markus Armbruster <armbru@redhat.com> lgtm Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > chardev/char-fe.c | 13 +++++++------ > 1 file changed, 7 insertions(+), 6 deletions(-) > > diff --git a/chardev/char-fe.c b/chardev/char-fe.c > index 20222a4cad..66cee8475a 100644 > --- a/chardev/char-fe.c > +++ b/chardev/char-fe.c > @@ -199,13 +199,18 @@ bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp) > MuxChardev *d = MUX_CHARDEV(s); > > if (d->mux_cnt >= MAX_MUX) { > - goto unavailable; > + error_setg(errp, > + "too many uses of multiplexed chardev '%s'" > + " (maximum is " stringify(MAX_MUX) ")", > + s->label); > + return false; > } > > d->backends[d->mux_cnt] = b; > tag = d->mux_cnt++; > } else if (s->be) { > - goto unavailable; > + error_setg(errp, "chardev '%s' is already in use", s->label); > + return false; > } else { > s->be = b; > } > @@ -215,10 +220,6 @@ bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp) > b->tag = tag; > b->chr = s; > return true; > - > -unavailable: > - error_setg(errp, QERR_DEVICE_IN_USE, s->label); QERR_DEVICE_IN_USE is now left with a single user in blockdev.c. Is it worth it?
Marc-André Lureau <marcandre.lureau@gmail.com> writes: > Hi > > On Wed, Mar 6, 2024 at 12:15 PM Markus Armbruster <armbru@redhat.com> wrote: >> >> Both >> >> $ qemu-system-x86_64 -chardev null,id=chr0,mux=on -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 >> >> and >> >> $ qemu-system-x86_64 -chardev null,id=chr0 -mon chardev=chr0 -mon chardev=chr0 >> fail with >> >> qemu-system-x86_64: -mon chardev=chr0: Device 'chr0' is in use >> >> Improve to >> >> qemu-system-x86_64: -mon chardev=chr0: too many uses of multiplexed chardev 'chr0' (maximum is 4) >> >> and >> >> qemu-system-x86_64: -mon chardev=chr0: chardev 'chr0' is already in use >> >> Signed-off-by: Markus Armbruster <armbru@redhat.com> > > lgtm > Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Thanks! [...] > QERR_DEVICE_IN_USE is now left with a single user in blockdev.c. Is it worth it? Nope, that one needs to go, too. How to reproduce it isn't obvious to me. I'll figure it out.
diff --git a/chardev/char-fe.c b/chardev/char-fe.c index 20222a4cad..66cee8475a 100644 --- a/chardev/char-fe.c +++ b/chardev/char-fe.c @@ -199,13 +199,18 @@ bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp) MuxChardev *d = MUX_CHARDEV(s); if (d->mux_cnt >= MAX_MUX) { - goto unavailable; + error_setg(errp, + "too many uses of multiplexed chardev '%s'" + " (maximum is " stringify(MAX_MUX) ")", + s->label); + return false; } d->backends[d->mux_cnt] = b; tag = d->mux_cnt++; } else if (s->be) { - goto unavailable; + error_setg(errp, "chardev '%s' is already in use", s->label); + return false; } else { s->be = b; } @@ -215,10 +220,6 @@ bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp) b->tag = tag; b->chr = s; return true; - -unavailable: - error_setg(errp, QERR_DEVICE_IN_USE, s->label); - return false; } void qemu_chr_fe_deinit(CharBackend *b, bool del)
Both $ qemu-system-x86_64 -chardev null,id=chr0,mux=on -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 -mon chardev=chr0 and $ qemu-system-x86_64 -chardev null,id=chr0 -mon chardev=chr0 -mon chardev=chr0 fail with qemu-system-x86_64: -mon chardev=chr0: Device 'chr0' is in use Improve to qemu-system-x86_64: -mon chardev=chr0: too many uses of multiplexed chardev 'chr0' (maximum is 4) and qemu-system-x86_64: -mon chardev=chr0: chardev 'chr0' is already in use Signed-off-by: Markus Armbruster <armbru@redhat.com> --- chardev/char-fe.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)