From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54342) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drOSv-0001yo-2T for qemu-devel@nongnu.org; Mon, 11 Sep 2017 09:09:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1drOSp-0002RS-AJ for qemu-devel@nongnu.org; Mon, 11 Sep 2017 09:09:29 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:35636) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1drOSp-0002QT-0a for qemu-devel@nongnu.org; Mon, 11 Sep 2017 09:09:23 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v8BD9Ctt103015 for ; Mon, 11 Sep 2017 09:09:21 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2cwq82gwgp-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 11 Sep 2017 09:09:19 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 11 Sep 2017 14:08:54 +0100 References: <20170908152446.14606-1-pasic@linux.vnet.ibm.com> <20170908152446.14606-4-pasic@linux.vnet.ibm.com> <20170911114841.408b5988.cohuck@redhat.com> From: Halil Pasic Date: Mon, 11 Sep 2017 15:08:52 +0200 MIME-Version: 1.0 In-Reply-To: <20170911114841.408b5988.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Message-Id: <90381836-c1ee-2d0b-86a5-117c2a86a74f@linux.vnet.ibm.com> Subject: Re: [Qemu-devel] [PATCH 3/4] s390x/css: remove dubious error handling branch List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Cornelia Huck Cc: Dong Jia Shi , Pierre Morel , qemu-devel@nongnu.org On 09/11/2017 11:48 AM, Cornelia Huck wrote: > On Fri, 8 Sep 2017 17:24:45 +0200 > Halil Pasic wrote: > > s/dubious/unused/ > Nod. >> The case in question actually never happens. Let us get rid of the dead >> code. > > I had tried to be complete in my initial implementation. With the > current implementation, it can never happen, yes. We can easily > resurrect it from git history should we need it in the future. > I've tried to understand the branch but I failed. Weather the subchannel is busy or not should be already decided, and if the device is busy that is probably supposed to be indicated via device status (word 2 bit 3). So I wrote dubious because I could not figure it out. But unused is certainly nicer. I think shall the need emerge the preferred way of handling would be to use the custom handling (-EIO) branch. >> >> Signed-off-by: Halil Pasic >> --- >> hw/s390x/css.c | 7 ------- >> 1 file changed, 7 deletions(-) >> >> diff --git a/hw/s390x/css.c b/hw/s390x/css.c >> index a44d87ab3e..a9cdd54efc 100644 >> --- a/hw/s390x/css.c >> +++ b/hw/s390x/css.c >> @@ -980,13 +980,6 @@ static void sch_handle_start_func_virtual(SubchDev *sch) >> SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; >> s->cpa = sch->channel_prog + 8; >> break; >> - case -EBUSY: >> - /* subchannel busy, generate deferred cc 1 */ >> - s->flags &= ~SCSW_FLAGS_MASK_CC; >> - s->flags |= (1 << 8); >> - s->ctrl &= ~SCSW_CTRL_MASK_STCTL; >> - s->ctrl |= SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; >> - break; >> case -EINPROGRESS: >> /* channel program has been suspended */ >> s->ctrl &= ~SCSW_ACTL_START_PEND; > > Thanks, queued. > Thanks!