From patchwork Wed Jul 25 13:24:27 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Maydell X-Patchwork-Id: 173168 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 0595A2C0098 for ; Wed, 25 Jul 2012 23:57:02 +1000 (EST) Received: from localhost ([::1]:42471 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Su25E-0007Fz-4e for incoming@patchwork.ozlabs.org; Wed, 25 Jul 2012 09:57:00 -0400 Received: from eggs.gnu.org ([208.118.235.92]:45113) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Su250-0007ER-RO for qemu-devel@nongnu.org; Wed, 25 Jul 2012 09:56:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Su24s-0001nA-GJ for qemu-devel@nongnu.org; Wed, 25 Jul 2012 09:56:46 -0400 Received: from mnementh.archaic.org.uk ([81.2.115.146]:39770) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Su24s-0001n3-8J for qemu-devel@nongnu.org; Wed, 25 Jul 2012 09:56:38 -0400 Received: from pm215 by mnementh.archaic.org.uk with local (Exim 4.72) (envelope-from ) id 1Su1Zo-0006aj-7H; Wed, 25 Jul 2012 14:24:32 +0100 From: Peter Maydell To: qemu-devel@nongnu.org Date: Wed, 25 Jul 2012 14:24:27 +0100 Message-Id: <1343222672-25312-2-git-send-email-peter.maydell@linaro.org> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1343222672-25312-1-git-send-email-peter.maydell@linaro.org> References: <1343222672-25312-1-git-send-email-peter.maydell@linaro.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) X-Received-From: 81.2.115.146 Cc: Alexander Graf , Marcelo Tosatti , Jan Kiszka , Avi Kivity , patches@linaro.org Subject: [Qemu-devel] [PATCH 1/6] kvm: Decouple 'interrupt injection is async' from 'kernel irqchip' 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 On x86 interrupt injection is asynchronous (and therefore VCPU idle management is done in the kernel) if and only if there is an in-kernel irqchip. On other architectures this isn't necessarily true (they may always do asynchronous injection), so define a new kvm_async_interrupt_injection() function instead of misusing kvm_irqchip_in_kernel(). Signed-off-by: Peter Maydell Acked-by: Jan Kiszka --- cpus.c | 3 ++- kvm-all.c | 7 ++++++- kvm-stub.c | 1 + kvm.h | 11 +++++++++++ 4 files changed, 20 insertions(+), 2 deletions(-) diff --git a/cpus.c b/cpus.c index 756e624..584b298 100644 --- a/cpus.c +++ b/cpus.c @@ -69,7 +69,8 @@ static bool cpu_thread_is_idle(CPUArchState *env) if (env->stopped || !runstate_is_running()) { return true; } - if (!env->halted || qemu_cpu_has_work(env) || kvm_irqchip_in_kernel()) { + if (!env->halted || qemu_cpu_has_work(env) || + kvm_async_interrupt_injection()) { return false; } return true; diff --git a/kvm-all.c b/kvm-all.c index 2148b20..3354c6f 100644 --- a/kvm-all.c +++ b/kvm-all.c @@ -100,6 +100,7 @@ struct KVMState KVMState *kvm_state; bool kvm_kernel_irqchip; +bool kvm_async_interrupt_injection; static const KVMCapabilityInfo kvm_required_capabilites[] = { KVM_CAP_INFO(USER_MEMORY), @@ -857,7 +858,7 @@ int kvm_irqchip_set_irq(KVMState *s, int irq, int level) struct kvm_irq_level event; int ret; - assert(kvm_irqchip_in_kernel()); + assert(kvm_async_interrupt_injection()); event.level = level; event.irq = irq; @@ -1201,6 +1202,10 @@ static int kvm_irqchip_create(KVMState *s) s->irqchip_inject_ioctl = KVM_IRQ_LINE_STATUS; } kvm_kernel_irqchip = true; + /* If we have an in-kernel IRQ chip then we must have asynchronous + * interrupt injection (though the reverse is not necessarily true) + */ + kvm_async_interrupt_injection = true; kvm_init_irq_routing(s); diff --git a/kvm-stub.c b/kvm-stub.c index d23b11c..b4023d1 100644 --- a/kvm-stub.c +++ b/kvm-stub.c @@ -19,6 +19,7 @@ KVMState *kvm_state; bool kvm_kernel_irqchip; +bool kvm_async_interrupt_injection; int kvm_init_vcpu(CPUArchState *env) { diff --git a/kvm.h b/kvm.h index 2617dd5..00abe36 100644 --- a/kvm.h +++ b/kvm.h @@ -24,13 +24,24 @@ extern int kvm_allowed; extern bool kvm_kernel_irqchip; +extern bool kvm_async_interrupt_injection; #if defined CONFIG_KVM || !defined NEED_CPU_H #define kvm_enabled() (kvm_allowed) #define kvm_irqchip_in_kernel() (kvm_kernel_irqchip) +/** + * kvm_async_interrupt_injection: + * + * Returns: true if we can inject interrupts into a KVM CPU + * asynchronously (ie by ioctl from any thread at any time) + * rather than having to do interrupt delivery synchronously + * (where the vcpu must be stopped at a suitable point first). + */ +#define kvm_async_interrupt_injection() (kvm_async_interrupt_injection) #else #define kvm_enabled() (0) #define kvm_irqchip_in_kernel() (false) +#define kvm_async_interrupt_injection() (false) #endif struct kvm_run;