From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:47477) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLHkN-0003Pd-0B for qemu-devel@nongnu.org; Mon, 08 Oct 2012 14:08:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TLHkL-0001hZ-0t for qemu-devel@nongnu.org; Mon, 08 Oct 2012 14:08:06 -0400 Received: from hall.aurel32.net ([88.191.126.93]:45261) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLHkK-0001hG-Qx for qemu-devel@nongnu.org; Mon, 08 Oct 2012 14:08:04 -0400 Date: Mon, 8 Oct 2012 20:07:56 +0200 From: Aurelien Jarno Message-ID: <20121008180756.GM4623@ohm.aurel32.net> References: <5073083C.1060201@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <5073083C.1060201@siemens.com> Subject: Re: [Qemu-devel] [PATCH] chardev: Use timer instead of bottom-half to postpone open event List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Peter Maydell , Anthony Liguori , qemu-devel , Paolo Bonzini On Mon, Oct 08, 2012 at 07:07:08PM +0200, Jan Kiszka wrote: > As the block layer may decide to flush bottom-halfs while the machine is > still initializing (e.g. to read geometry data from the disk), our > postponed open event may be processed before the last frontend > registered with a muxed chardev. Until the semantics of BHs have been > clarified, use an expired timer to achieve the same effect (suggested > by Paolo Bonzini). > > Signed-off-by: Jan Kiszka > --- > > This obsoletes the versatilepb hack. > > qemu-char.c | 13 +++++++------ > qemu-char.h | 2 +- > 2 files changed, 8 insertions(+), 7 deletions(-) > > diff --git a/qemu-char.c b/qemu-char.c > index f9ee2f0..fb4e3dc 100644 > --- a/qemu-char.c > +++ b/qemu-char.c > @@ -123,19 +123,20 @@ void qemu_chr_be_event(CharDriverState *s, int event) > s->chr_event(s->handler_opaque, event); > } > > -static void qemu_chr_generic_open_bh(void *opaque) > +static void qemu_chr_fire_open_event(void *opaque) > { > CharDriverState *s = opaque; > qemu_chr_be_event(s, CHR_EVENT_OPENED); > - qemu_bh_delete(s->bh); > - s->bh = NULL; > + qemu_free_timer(s->open_timer); > + s->open_timer = NULL; > } > > void qemu_chr_generic_open(CharDriverState *s) > { > - if (s->bh == NULL) { > - s->bh = qemu_bh_new(qemu_chr_generic_open_bh, s); > - qemu_bh_schedule(s->bh); > + if (s->open_timer == NULL) { > + s->open_timer = qemu_new_timer_ms(vm_clock, > + qemu_chr_fire_open_event, s); > + qemu_mod_timer(s->open_timer, qemu_get_clock_ms(vm_clock) - 1); > } > } > > diff --git a/qemu-char.h b/qemu-char.h > index 486644b..297dd98 100644 > --- a/qemu-char.h > +++ b/qemu-char.h > @@ -69,7 +69,7 @@ struct CharDriverState { > void (*chr_guest_open)(struct CharDriverState *chr); > void (*chr_guest_close)(struct CharDriverState *chr); > void *opaque; > - QEMUBH *bh; > + QEMUTimer *open_timer; > char *label; > char *filename; > int opened; It works for me on both MIPS malta and ARM versatile. Thanks. Tested-by: Aurelien Jarno -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurelien@aurel32.net http://www.aurel32.net