From patchwork Tue Oct 4 11:28:25 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 117604 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 8DDBAB6F7E for ; Tue, 4 Oct 2011 22:28:39 +1100 (EST) Received: from localhost ([::1]:54005 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RB3Aq-00074A-QK for incoming@patchwork.ozlabs.org; Tue, 04 Oct 2011 07:28:36 -0400 Received: from eggs.gnu.org ([140.186.70.92]:57760) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RB3Ak-00072w-Hb for qemu-devel@nongnu.org; Tue, 04 Oct 2011 07:28:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RB3Aj-0002Yd-8x for qemu-devel@nongnu.org; Tue, 04 Oct 2011 07:28:30 -0400 Received: from mtagate7.uk.ibm.com ([194.196.100.167]:54839) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RB3Aj-0002Y7-1L for qemu-devel@nongnu.org; Tue, 04 Oct 2011 07:28:29 -0400 Received: from d06nrmr1806.portsmouth.uk.ibm.com (d06nrmr1806.portsmouth.uk.ibm.com [9.149.39.193]) by mtagate7.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p94BSQR4025700 for ; Tue, 4 Oct 2011 11:28:26 GMT Received: from d06av01.portsmouth.uk.ibm.com (d06av01.portsmouth.uk.ibm.com [9.149.37.212]) by d06nrmr1806.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p94BSQr22482396 for ; Tue, 4 Oct 2011 12:28:26 +0100 Received: from d06av01.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av01.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p94BSP2c032590 for ; Tue, 4 Oct 2011 05:28:26 -0600 Received: from [9.152.224.64] (dyn-9-152-224-64.boeblingen.de.ibm.com [9.152.224.64]) by d06av01.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p94BSPpL032584; Tue, 4 Oct 2011 05:28:25 -0600 Message-ID: <4E8AEDD9.1000401@de.ibm.com> Date: Tue, 04 Oct 2011 13:28:25 +0200 From: Christian Borntraeger User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.23) Gecko/20110921 Lightning/1.0b2 Thunderbird/3.1.15 MIME-Version: 1.0 To: Alexander Graf X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 194.196.100.167 Cc: Carsten Otte , qemu-devel@nongnu.org Subject: [Qemu-devel] s390: Fix cpu shutdown for KVM X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org qemu/kvm on s390 currently hangs on panic (doesnt exit on disabled wait) and also shuts down on cpu hot-unplug (SIGP stop). This patch tries to fix these simple cases. On s390 a shutdown is the state of all CPUs being either stopped or disabled (for interrupts) waiting. We have to track this number to call the shutdown sequence accordingly. This patch implements the counting and shutdown handling for the kvm path in qemu. Signed-off-by: Christian Borntraeger --- hw/s390-virtio.c | 4 ++++ target-s390x/kvm.c | 29 +++++++++++++++++++++++++---- 2 files changed, 29 insertions(+), 4 deletions(-) Index: b/hw/s390-virtio.c =================================================================== --- a/hw/s390-virtio.c +++ b/hw/s390-virtio.c @@ -130,6 +130,9 @@ int s390_virtio_hypercall(CPUState *env, return r; } +/* defined in target-s390x/kvm.c */ +extern int s390_running_cpus; + /* PC hardware initialisation */ static void s390_init(ram_addr_t my_ram_size, const char *boot_device, @@ -189,6 +192,7 @@ static void s390_init(ram_addr_t my_ram_ env->halted = 0; env->exception_index = 0; + s390_running_cpus = 1; if (kernel_filename) { kernel_size = load_image(kernel_filename, qemu_get_ram_ptr(0)); Index: b/target-s390x/kvm.c =================================================================== --- a/target-s390x/kvm.c +++ b/target-s390x/kvm.c @@ -63,6 +63,14 @@ #define SCLP_CMDW_READ_SCP_INFO 0x00020001 #define SCLP_CMDW_READ_SCP_INFO_FORCED 0x00120001 +/* + * The number of running CPUs. On s390 a shutdown is the state of all CPUs + * being either stopped or disabled (for interrupts) waiting. We have to + * track this number to call the shutdown sequence accordingly. This + * number is modified either on startup or while holding the big qemu lock. + */ +int s390_running_cpus; + const KVMCapabilityInfo kvm_arch_required_capabilities[] = { KVM_CAP_LAST_INFO }; @@ -185,6 +193,12 @@ void kvm_s390_interrupt_internal(CPUStat return; } + /* + * We can only deliver interrupts to (interrupt) enabled CPUs. + * We dont modify s390_running_cpus here, since CPUs in enabled wait + * will wait inside the kernel (no exit). Therefore, the targeted + * CPUs was neither disabled waiting or stopped for qemu. + */ env->halted = 0; env->exception_index = -1; qemu_cpu_kick(env); @@ -301,6 +315,7 @@ static int s390_cpu_restart(CPUState *en kvm_s390_interrupt(env, KVM_S390_RESTART, 0); env->halted = 0; env->exception_index = -1; + s390_running_cpus++; qemu_cpu_kick(env); dprintf("DONE: SIGP cpu restart: %p\n", env); return 0; @@ -425,16 +440,24 @@ static int handle_intercept(CPUState *en r = handle_instruction(env, run); break; case ICPT_WAITPSW: - /* XXX What to do on system shutdown? */ + if (--s390_running_cpus == 0) { + qemu_system_shutdown_request(); + } env->halted = 1; env->exception_index = EXCP_HLT; + r = EXCP_HALTED; break; case ICPT_SOFT_INTERCEPT: fprintf(stderr, "KVM unimplemented icpt SOFT\n"); exit(1); break; case ICPT_CPU_STOP: - qemu_system_shutdown_request(); + if (--s390_running_cpus == 0) { + qemu_system_shutdown_request(); + } + env->halted = 1; + env->exception_index = EXCP_HLT; + r = EXCP_HALTED; break; case ICPT_IO: fprintf(stderr, "KVM unimplemented icpt IO\n"); @@ -468,8 +491,6 @@ int kvm_arch_handle_exit(CPUState *env, if (ret == 0) { ret = EXCP_INTERRUPT; - } else if (ret > 0) { - ret = 0; } return ret; }