From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36589) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c1yj2-00040E-2q for qemu-devel@nongnu.org; Wed, 02 Nov 2016 12:49:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c1yiy-0007IU-0v for qemu-devel@nongnu.org; Wed, 02 Nov 2016 12:49:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59702) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1c1yix-0007He-RE for qemu-devel@nongnu.org; Wed, 02 Nov 2016 12:49:15 -0400 References: <20161102142559.23395-1-bobby.prani@gmail.com> <20161102164008.28401-1-bobby.prani@gmail.com> From: Paolo Bonzini Message-ID: <639cd027-f6db-d66d-c664-d5430831cddf@redhat.com> Date: Wed, 2 Nov 2016 17:49:11 +0100 MIME-Version: 1.0 In-Reply-To: <20161102164008.28401-1-bobby.prani@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] mttcg: Handle EXCP_ATOMIC exception List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Pranith Kumar , qemu-devel@nongnu.org, alex.bennee@linaro.org On 02/11/2016 17:40, Pranith Kumar wrote: > The patch enables handling atomic code in the guest. This should be > preferably done in cpu_handle_exception(), but the current assumptions > regarding when we can execute atomic sections cause a deadlock. > > Signed-off-by: Pranith Kumar > --- > cpus.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/cpus.c b/cpus.c > index 8f98060..299ce7e 100644 > --- a/cpus.c > +++ b/cpus.c > @@ -1315,6 +1315,11 @@ static void *qemu_tcg_rr_cpu_thread_fn(void *arg) > if (r == EXCP_DEBUG) { > cpu_handle_guest_debug(cpu); > break; > + } else if (r == EXCP_ATOMIC) { > + qemu_mutex_unlock_iothread(); > + cpu_exec_step_atomic(cpu); > + qemu_mutex_lock_iothread(); > + break; > } > } else if (cpu->stop) { > if (cpu->unplug) { > @@ -1385,6 +1390,10 @@ static void *qemu_tcg_cpu_thread_fn(void *arg) > */ > g_assert(cpu->halted); > break; > + case EXCP_ATOMIC: > + qemu_mutex_unlock_iothread(); > + cpu_exec_step_atomic(cpu); > + qemu_mutex_lock_iothread(); > default: > /* Ignore everything else? */ > break; > Alex, please pick up this patch yourself. Paolo