Received: from eggs.gnu.org ([2001:4830:134:3::10]:51101) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fI9iS-0007m9-Ui for qemu-devel@nongnu.org; Mon, 14 May 2018 05:24:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fI9iN-0003re-Uw for qemu-devel@nongnu.org; Mon, 14 May 2018 05:24:24 -0400 Date: Mon, 14 May 2018 11:24:11 +0200 From: Cornelia Huck Message-ID: <20180514112411.68a399fa.cohuck@redhat.com> In-Reply-To: <20180424101859.10239-1-david@redhat.com> References: <20180424101859.10239-1-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v1] s390x: refactor reset/reipl handling List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Hildenbrand Cc: qemu-s390x@nongnu.org, qemu-devel@nongnu.org, Richard Henderson , Alexander Graf , Christian Borntraeger , Thomas Huth , Paolo Bonzini On Tue, 24 Apr 2018 12:18:59 +0200 David Hildenbrand wrote: > Calling pause_all_vcpus()/resume_all_vcpus() from a VCPU thread might > not be the best idea. As pause_all_vcpus() temporarily drops the qemu > mutex, two parallel calls to pause_all_vcpus() can be active at a time, > resulting in a deadlock. (either by two VCPUs or by the main thread and a > VCPU) > > Let's handle it via the main loop instead, as suggested by Paolo. If we > would have two parallel reset requests by two different VCPUs at the > same time, the last one would win. > > We use the existing ipl device to handle it. The nice side effect is > that we can get rid of reipl_requested. > > This change implies that all reset handling now goes via the common > path, so "no-reboot" handling is now active for all kinds of reboots. > > Let's execute any CPU initialization code on the target CPU using > run_on_cpu. > > Signed-off-by: David Hildenbrand > --- > > RFC -> v1: > - initital -> initial > - get rid of goto > - store CPU index instead of CPU. Fallback to any CPU in case not found > - handle default case in switch-case > > hw/s390x/ipl.c | 43 +++++++++++++++++++++++---- > hw/s390x/ipl.h | 16 ++++++++-- > hw/s390x/s390-virtio-ccw.c | 51 ++++++++++++++++++++++++++----- > include/hw/s390x/s390-virtio-ccw.h | 2 -- > target/s390x/cpu.h | 26 ++++++++++++++++ > target/s390x/diag.c | 61 +++----------------------------------- > target/s390x/internal.h | 6 ---- > target/s390x/kvm.c | 2 +- > 8 files changed, 127 insertions(+), 80 deletions(-) Thanks, applied.