From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56728) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bFjOU-0006k4-BX for qemu-devel@nongnu.org; Wed, 22 Jun 2016 10:44:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bFjOQ-0001H7-4y for qemu-devel@nongnu.org; Wed, 22 Jun 2016 10:44:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58306) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bFjOP-0001H1-Sc for qemu-devel@nongnu.org; Wed, 22 Jun 2016 10:44:38 -0400 Date: Wed, 22 Jun 2016 15:44:33 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20160622144432.GB6604@work-vm> References: <1466432945-28682-1-git-send-email-pbonzini@redhat.com> <1466432945-28682-2-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1466432945-28682-2-git-send-email-pbonzini@redhat.com> Subject: Re: [Qemu-devel] [PATCH 1/6] serial: make tsr_retry unsigned List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org, bcketchum@gmail.com * Paolo Bonzini (pbonzini@redhat.com) wrote: > It can never become negative; reflect this in the type of the field > and simplify the conditions. OK, yes, the one case that could make it go -ve was removed in fcfb4d6 somewhere after 1.4.0. > Signed-off-by: Paolo Bonzini > --- > hw/char/serial.c | 12 ++++++++---- > include/hw/char/serial.h | 2 +- > 2 files changed, 9 insertions(+), 5 deletions(-) > > diff --git a/hw/char/serial.c b/hw/char/serial.c > index 6d815b5..e65e9e0 100644 > --- a/hw/char/serial.c > +++ b/hw/char/serial.c > @@ -229,7 +229,7 @@ static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) > > do { > assert(!(s->lsr & UART_LSR_TEMT)); > - if (s->tsr_retry <= 0) { > + if (s->tsr_retry == 0) { > assert(!(s->lsr & UART_LSR_THRE)); > > if (s->fcr & UART_FCR_FE) { > @@ -252,7 +252,7 @@ static gboolean serial_xmit(GIOChannel *chan, GIOCondition cond, void *opaque) > /* in loopback mode, say that we just received a char */ > serial_receive1(s, &s->tsr, 1); > } else if (qemu_chr_fe_write(s->chr, &s->tsr, 1) != 1) { > - if (s->tsr_retry >= 0 && s->tsr_retry < MAX_XMIT_RETRY && > + if (s->tsr_retry < MAX_XMIT_RETRY && > qemu_chr_fe_add_watch(s->chr, G_IO_OUT|G_IO_HUP, > serial_xmit, s) > 0) { > s->tsr_retry++; > @@ -330,7 +330,7 @@ static void serial_ioport_write(void *opaque, hwaddr addr, uint64_t val, > s->lsr &= ~UART_LSR_THRE; > s->lsr &= ~UART_LSR_TEMT; > serial_update_irq(s); > - if (s->tsr_retry <= 0) { > + if (s->tsr_retry == 0) { > serial_xmit(NULL, G_IO_OUT, s); > } > } > @@ -639,6 +639,10 @@ static int serial_post_load(void *opaque, int version_id) > if (s->thr_ipending == -1) { > s->thr_ipending = ((s->iir & UART_IIR_ID) == UART_IIR_THRI); > } > + if (s->tsr_retry > MAX_XMIT_RETRY) { > + s->tsr_retry = MAX_XMIT_RETRY; > + } Good that makes it safe even after receiving the case that could be -1. Reviewed-by: Dr. David Alan Gilbert > s->last_break_enable = (s->lcr >> 6) & 1; > /* Initialize fcr via setter to perform essential side-effects */ > serial_write_fcr(s, s->fcr_vmstate); > @@ -685,7 +689,7 @@ static const VMStateDescription vmstate_serial_tsr = { > .minimum_version_id = 1, > .needed = serial_tsr_needed, > .fields = (VMStateField[]) { > - VMSTATE_INT32(tsr_retry, SerialState), > + VMSTATE_UINT32(tsr_retry, SerialState), > VMSTATE_UINT8(thr, SerialState), > VMSTATE_UINT8(tsr, SerialState), > VMSTATE_END_OF_LIST() > diff --git a/include/hw/char/serial.h b/include/hw/char/serial.h > index 15beb6b..ef90615 100644 > --- a/include/hw/char/serial.h > +++ b/include/hw/char/serial.h > @@ -55,7 +55,7 @@ struct SerialState { > int last_break_enable; > int it_shift; > int baudbase; > - int tsr_retry; > + unsigned tsr_retry; > uint32_t wakeup; > > /* Time when the last byte was successfully sent out of the tsr */ > -- > 2.5.5 > > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK