From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E65D7ECAAA1 for ; Mon, 5 Sep 2022 07:05:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237012AbiIEHFU (ORCPT ); Mon, 5 Sep 2022 03:05:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236854AbiIEHFR (ORCPT ); Mon, 5 Sep 2022 03:05:17 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E615930F7A; Mon, 5 Sep 2022 00:05:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662361515; x=1693897515; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=dSaImXYJDFJBjVkAy9D9i/aVykAxDgVnwzzvJ+cCifE=; b=caaVPj9U2W+gjdGcviWv1oL7xoABbkUz0qMJn7UUkt68VsMYYi+UhCMk Qtz10BQ4wNukKrqHaiP3AILdWQue6xv5nexnidmhOqd45Je1L2S8GiH+k W6MfYS32hh++6cDrmE4UJkgYkUX2JzvZiDtjTqvZ9NFM7B3Au0oI1IyqM Nxv1gbLDMT7gmM/p8lx2viF1hTkVT+afYX2LZQagdlEaeOjKo8f2v4vBp 8GZiIlJAs4b/k6UB5hv+YCx9NfnDk5XoLMqAflzWPoteNc7wrITYn8SZf R6Z+TiWjTCO2fdke3pIPXZdUCwMcm0Og/zxyWxsm0l40C+uJt/10tO4Oq w==; X-IronPort-AV: E=McAfee;i="6500,9779,10460"; a="293908122" X-IronPort-AV: E=Sophos;i="5.93,290,1654585200"; d="scan'208";a="293908122" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Sep 2022 00:05:15 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.93,290,1654585200"; d="scan'208";a="643690288" Received: from yy-desk-7060.sh.intel.com (HELO localhost) ([10.239.159.76]) by orsmga008.jf.intel.com with ESMTP; 05 Sep 2022 00:05:10 -0700 Date: Mon, 5 Sep 2022 15:05:09 +0800 From: Yuan Yao To: isaku.yamahata@intel.com Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Marc Zyngier , Will Deacon , isaku.yamahata@gmail.com, Kai Huang , Chao Gao , Atish Patra , Shaokun Zhang , Qi Liu , John Garry , Daniel Lezcano , Huang Ying , Huacai Chen , Dave Hansen , Borislav Petkov , Oliver Upton Subject: Re: [PATCH v3 06/22] KVM: arm64: Simplify the CPUHP logic Message-ID: <20220905070509.f5neutyqgvbklefi@yy-desk-7060> References: <72481a7bc0ff08093f4f0f04cece877ee82de0cf.1662084396.git.isaku.yamahata@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <72481a7bc0ff08093f4f0f04cece877ee82de0cf.1662084396.git.isaku.yamahata@intel.com> User-Agent: NeoMutt/20171215 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 01, 2022 at 07:17:41PM -0700, isaku.yamahata@intel.com wrote: > From: Marc Zyngier > > For a number of historical reasons, the KVM/arm64 hotplug setup is pretty > complicated, and we have two extra CPUHP notifiers for vGIC and timers. > > It looks pretty pointless, and gets in the way of further changes. > So let's just expose some helpers that can be called from the core > CPUHP callback, and get rid of everything else. > > This gives us the opportunity to drop a useless notifier entry, > as well as tidy-up the timer enable/disable, which was a bit odd. > > Signed-off-by: Marc Zyngier > Signed-off-by: Chao Gao > Reviewed-by: Oliver Upton > Link: https://lore.kernel.org/r/20220216031528.92558-5-chao.gao@intel.com > Signed-off-by: Isaku Yamahata > --- > arch/arm64/kvm/arch_timer.c | 27 ++++++++++----------------- > arch/arm64/kvm/arm.c | 4 ++++ > arch/arm64/kvm/vgic/vgic-init.c | 19 ++----------------- > include/kvm/arm_arch_timer.h | 4 ++++ > include/kvm/arm_vgic.h | 4 ++++ > include/linux/cpuhotplug.h | 3 --- > 6 files changed, 24 insertions(+), 37 deletions(-) > > diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c > index bb24a76b4224..33fca1a691a5 100644 > --- a/arch/arm64/kvm/arch_timer.c > +++ b/arch/arm64/kvm/arch_timer.c > @@ -811,10 +811,18 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) > ptimer->host_timer_irq_flags = host_ptimer_irq_flags; > } > > -static void kvm_timer_init_interrupt(void *info) > +void kvm_timer_cpu_up(void) > { > enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags); > - enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags); > + if (host_ptimer_irq) > + enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags); > +} > + > +void kvm_timer_cpu_down(void) > +{ > + disable_percpu_irq(host_vtimer_irq); > + if (host_ptimer_irq) > + disable_percpu_irq(host_ptimer_irq); > } Should "host_vtimer_irq" be checked yet as host_ptimer_irq ? Because the host_{v,p}timer_irq is set in same function kvm_irq_init() which called AFTER the on_each_cpu(_kvm_arch_hardware_enable, NULL, 1) from init_subsystems(): kvm_init() kvm_arch_init() init_subsystems() on_each_cpu(_kvm_arch_hardware_enable, NULL, 1); kvm_timer_hyp_init() kvm_irq_init() host_vtimer_irq = info->virtual_irq; host_ptimer_irq = info->physical_irq; hardware_enable_all() > > int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) > @@ -976,18 +984,6 @@ void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu, > preempt_enable(); > } > > -static int kvm_timer_starting_cpu(unsigned int cpu) > -{ > - kvm_timer_init_interrupt(NULL); > - return 0; > -} > - > -static int kvm_timer_dying_cpu(unsigned int cpu) > -{ > - disable_percpu_irq(host_vtimer_irq); > - return 0; > -} > - > static int timer_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu) > { > if (vcpu) > @@ -1185,9 +1181,6 @@ int kvm_timer_hyp_init(bool has_gic) > goto out_free_irq; > } > > - cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING, > - "kvm/arm/timer:starting", kvm_timer_starting_cpu, > - kvm_timer_dying_cpu); > return 0; > out_free_irq: > free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus()); > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 3385fb57c11a..0a2f616c4d63 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1670,6 +1670,8 @@ static void _kvm_arch_hardware_enable(void *discard) > { > if (!__this_cpu_read(kvm_arm_hardware_enabled)) { > cpu_hyp_reinit(); > + kvm_vgic_cpu_up(); > + kvm_timer_cpu_up(); > __this_cpu_write(kvm_arm_hardware_enabled, 1); > } > } > @@ -1683,6 +1685,8 @@ int kvm_arch_hardware_enable(void) > static void _kvm_arch_hardware_disable(void *discard) > { > if (__this_cpu_read(kvm_arm_hardware_enabled)) { > + kvm_timer_cpu_down(); > + kvm_vgic_cpu_down(); > cpu_hyp_reset(); > __this_cpu_write(kvm_arm_hardware_enabled, 0); > } > diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c > index f6d4f4052555..6c7f6ae21ec0 100644 > --- a/arch/arm64/kvm/vgic/vgic-init.c > +++ b/arch/arm64/kvm/vgic/vgic-init.c > @@ -465,17 +465,15 @@ int kvm_vgic_map_resources(struct kvm *kvm) > > /* GENERIC PROBE */ > > -static int vgic_init_cpu_starting(unsigned int cpu) > +void kvm_vgic_cpu_up(void) > { > enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0); > - return 0; > } > > > -static int vgic_init_cpu_dying(unsigned int cpu) > +void kvm_vgic_cpu_down(void) > { > disable_percpu_irq(kvm_vgic_global_state.maint_irq); > - return 0; > } > > static irqreturn_t vgic_maintenance_handler(int irq, void *data) > @@ -584,19 +582,6 @@ int kvm_vgic_hyp_init(void) > return ret; > } > > - ret = cpuhp_setup_state(CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING, > - "kvm/arm/vgic:starting", > - vgic_init_cpu_starting, vgic_init_cpu_dying); > - if (ret) { > - kvm_err("Cannot register vgic CPU notifier\n"); > - goto out_free_irq; > - } > - > kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq); > return 0; > - > -out_free_irq: > - free_percpu_irq(kvm_vgic_global_state.maint_irq, > - kvm_get_running_vcpus()); > - return ret; > } > diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h > index cd6d8f260eab..1638418f72dd 100644 > --- a/include/kvm/arm_arch_timer.h > +++ b/include/kvm/arm_arch_timer.h > @@ -104,4 +104,8 @@ void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu, > u32 timer_get_ctl(struct arch_timer_context *ctxt); > u64 timer_get_cval(struct arch_timer_context *ctxt); > > +/* CPU HP callbacks */ > +void kvm_timer_cpu_up(void); > +void kvm_timer_cpu_down(void); > + > #endif > diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h > index 4df9e73a8bb5..fc4acc91ba06 100644 > --- a/include/kvm/arm_vgic.h > +++ b/include/kvm/arm_vgic.h > @@ -431,4 +431,8 @@ int vgic_v4_load(struct kvm_vcpu *vcpu); > void vgic_v4_commit(struct kvm_vcpu *vcpu); > int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db); > > +/* CPU HP callbacks */ > +void kvm_vgic_cpu_up(void); > +void kvm_vgic_cpu_down(void); > + > #endif /* __KVM_ARM_VGIC_H */ > diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h > index f61447913db9..7337414e4947 100644 > --- a/include/linux/cpuhotplug.h > +++ b/include/linux/cpuhotplug.h > @@ -186,9 +186,6 @@ enum cpuhp_state { > CPUHP_AP_TI_GP_TIMER_STARTING, > CPUHP_AP_HYPERV_TIMER_STARTING, > CPUHP_AP_KVM_STARTING, > - CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING, > - CPUHP_AP_KVM_ARM_VGIC_STARTING, > - CPUHP_AP_KVM_ARM_TIMER_STARTING, > /* Must be the last timer callback */ > CPUHP_AP_DUMMY_TIMER_STARTING, > CPUHP_AP_ARM_XEN_STARTING, > -- > 2.25.1 >