From patchwork Sat Nov 4 08:57:53 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bibo Mao X-Patchwork-Id: 13445444 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B6893C2CF for ; Sat, 4 Nov 2023 08:59:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B36851BF; Sat, 4 Nov 2023 01:59:25 -0700 (PDT) Received: from loongson.cn (unknown [10.2.5.213]) by gateway (Coremail) with SMTP id _____8DxqOqVB0Zl1+E2AA--.6334S3; Sat, 04 Nov 2023 16:57:57 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.213]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxbS+UB0ZlmGs5AA--.59322S3; Sat, 04 Nov 2023 16:57:57 +0800 (CST) From: Bibo Mao To: Tianrui Zhao , Huacai Chen Cc: WANG Xuerui , kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v1 1/3] LoongArch: KVM: Remove SW timer switch during vcpu block flow Date: Sat, 4 Nov 2023 16:57:53 +0800 Message-Id: <20231104085755.930439-2-maobibo@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231104085755.930439-1-maobibo@loongson.cn> References: <20231104085755.930439-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8CxbS+UB0ZlmGs5AA--.59322S3 X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ X-Coremail-Antispam: 1Uk129KBj93XoW7ur45Ar18Wr1kJF48JFWDGFX_yoW8uF4fpF W7Crnaqw4rWr1kK3srtw4kWr4UXw4kKF1fXasrAFW5Ar1qyF18tF4rKrWqqFy5Kw4rCFyf Zr1rK3W5uF15A3cCm3ZEXasCq-sJn29KB7ZKAUJUUUU5529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUkFb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r126r13M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Jr0_Gr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12xvs2x26I8E6xACxx 1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv 67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41l42xK82IYc2 Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s02 6x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE 42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6x kF7I0E14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x07jjpB-UUUUU= When idle instruction is emulation, kvm will check whether there is pending interrupts including timer interrupt. HW timer event checking is used now, so it is not necessary to switch to sw timer during vcpu block checking flow, since hw timer pending interrupt can be set directly with CSR staus register. This patch adds preemption disabling during checking hw CSR status register, and removes SW timer mode switching in idle instruction emulation function. Signed-off-by: Bibo Mao --- arch/loongarch/kvm/exit.c | 11 +---------- arch/loongarch/kvm/vcpu.c | 9 ++++++++- 2 files changed, 9 insertions(+), 11 deletions(-) diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index ce8de3fa472c..d2a38cd47032 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -200,17 +200,8 @@ int kvm_emu_idle(struct kvm_vcpu *vcpu) ++vcpu->stat.idle_exits; trace_kvm_exit_idle(vcpu, KVM_TRACE_EXIT_IDLE); - if (!kvm_arch_vcpu_runnable(vcpu)) { - /* - * Switch to the software timer before halt-polling/blocking as - * the guest's timer may be a break event for the vCPU, and the - * hypervisor timer runs only when the CPU is in guest mode. - * Switch before halt-polling so that KVM recognizes an expired - * timer before blocking. - */ - kvm_save_timer(vcpu); + if (!kvm_arch_vcpu_runnable(vcpu)) kvm_vcpu_block(vcpu); - } return EMULATE_DONE; } diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c index 73d0c2b9c1a5..42663a345bd1 100644 --- a/arch/loongarch/kvm/vcpu.c +++ b/arch/loongarch/kvm/vcpu.c @@ -187,8 +187,15 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) { - return kvm_pending_timer(vcpu) || + int ret; + + /* protect from TOD sync and vcpu_load/put */ + preempt_disable(); + ret = kvm_pending_timer(vcpu) || kvm_read_hw_gcsr(LOONGARCH_CSR_ESTAT) & (1 << INT_TI); + preempt_enable(); + + return ret; } int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu) From patchwork Sat Nov 4 08:57:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bibo Mao X-Patchwork-Id: 13445443 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BFE74C2C7 for ; Sat, 4 Nov 2023 08:58:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4851F1BC; Sat, 4 Nov 2023 01:58:00 -0700 (PDT) Received: from loongson.cn (unknown [10.2.5.213]) by gateway (Coremail) with SMTP id _____8AxZ+iVB0Zl2+E2AA--.6405S3; Sat, 04 Nov 2023 16:57:57 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.213]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxbS+UB0ZlmGs5AA--.59322S4; Sat, 04 Nov 2023 16:57:57 +0800 (CST) From: Bibo Mao To: Tianrui Zhao , Huacai Chen Cc: WANG Xuerui , kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v1 2/3] LoongArch: KVM: Allow to access HW timer CSR registers always Date: Sat, 4 Nov 2023 16:57:54 +0800 Message-Id: <20231104085755.930439-3-maobibo@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231104085755.930439-1-maobibo@loongson.cn> References: <20231104085755.930439-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8CxbS+UB0ZlmGs5AA--.59322S4 X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ X-Coremail-Antispam: 1Uk129KBj93XoW7uFW7XFyDXw47WrW7CF13KFX_yoW5JrWDpr WakF9rtr48tryqqFyDJrs8uF15CrZ7K34xWF17AFW2yr12vr1rJF97Gr97XFWYqa4SqFWS vryrCwn0vF4DXwbCm3ZEXasCq-sJn29KB7ZKAUJUUUU8529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUkFb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1a6r1DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12xvs2x26I8E6xACxx 1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1q6rW5McIj6I8E87Iv 67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41l42xK82IYc2 Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s02 6x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE 42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6x kF7I0E14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x07UgjjgUUUUU= Currently HW timer CSR registers are allowed to access before entering to vm and disabled if switch to SW timer in host mode, instead it is not necessary to do so. HW timer CSR registers can be accessed always, it is nothing to do with whether it is in vm mode or host mode. This patch removes the limitation. Signed-off-by: Bibo Mao --- arch/loongarch/kvm/main.c | 1 - arch/loongarch/kvm/timer.c | 27 ++++++--------------------- 2 files changed, 6 insertions(+), 22 deletions(-) diff --git a/arch/loongarch/kvm/main.c b/arch/loongarch/kvm/main.c index 1c1d5199500e..86a2f2d0cb27 100644 --- a/arch/loongarch/kvm/main.c +++ b/arch/loongarch/kvm/main.c @@ -287,7 +287,6 @@ int kvm_arch_hardware_enable(void) if (env & CSR_GCFG_MATC_ROOT) gcfg |= CSR_GCFG_MATC_ROOT; - gcfg |= CSR_GCFG_TIT; write_csr_gcfg(gcfg); kvm_flush_tlb_all(); diff --git a/arch/loongarch/kvm/timer.c b/arch/loongarch/kvm/timer.c index 284bf553fefe..1d29bd21a9da 100644 --- a/arch/loongarch/kvm/timer.c +++ b/arch/loongarch/kvm/timer.c @@ -70,15 +70,6 @@ void kvm_init_timer(struct kvm_vcpu *vcpu, unsigned long timer_hz) */ void kvm_acquire_timer(struct kvm_vcpu *vcpu) { - unsigned long cfg; - - cfg = read_csr_gcfg(); - if (!(cfg & CSR_GCFG_TIT)) - return; - - /* Enable guest access to hard timer */ - write_csr_gcfg(cfg & ~CSR_GCFG_TIT); - /* * Freeze the soft-timer and sync the guest stable timer with it. We do * this with interrupts disabled to avoid latency. @@ -168,21 +159,15 @@ static void _kvm_save_timer(struct kvm_vcpu *vcpu) */ void kvm_save_timer(struct kvm_vcpu *vcpu) { - unsigned long cfg; struct loongarch_csrs *csr = vcpu->arch.csr; preempt_disable(); - cfg = read_csr_gcfg(); - if (!(cfg & CSR_GCFG_TIT)) { - /* Disable guest use of hard timer */ - write_csr_gcfg(cfg | CSR_GCFG_TIT); - - /* Save hard timer state */ - kvm_save_hw_gcsr(csr, LOONGARCH_CSR_TCFG); - kvm_save_hw_gcsr(csr, LOONGARCH_CSR_TVAL); - if (kvm_read_sw_gcsr(csr, LOONGARCH_CSR_TCFG) & CSR_TCFG_EN) - _kvm_save_timer(vcpu); - } + + /* Save hard timer state */ + kvm_save_hw_gcsr(csr, LOONGARCH_CSR_TCFG); + kvm_save_hw_gcsr(csr, LOONGARCH_CSR_TVAL); + if (kvm_read_sw_gcsr(csr, LOONGARCH_CSR_TCFG) & CSR_TCFG_EN) + _kvm_save_timer(vcpu); /* Save timer-related state to vCPU context */ kvm_save_hw_gcsr(csr, LOONGARCH_CSR_ESTAT); From patchwork Sat Nov 4 08:57:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bibo Mao X-Patchwork-Id: 13445442 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3814C155 for ; Sat, 4 Nov 2023 08:58:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A3D30194; Sat, 4 Nov 2023 01:58:00 -0700 (PDT) Received: from loongson.cn (unknown [10.2.5.213]) by gateway (Coremail) with SMTP id _____8Cxh+iVB0Zl3uE2AA--.6535S3; Sat, 04 Nov 2023 16:57:57 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.213]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxbS+UB0ZlmGs5AA--.59322S5; Sat, 04 Nov 2023 16:57:57 +0800 (CST) From: Bibo Mao To: Tianrui Zhao , Huacai Chen Cc: WANG Xuerui , kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v1 3/3] LoongArch: KVM: Remove kvm_acquire_timer before entering guest Date: Sat, 4 Nov 2023 16:57:55 +0800 Message-Id: <20231104085755.930439-4-maobibo@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231104085755.930439-1-maobibo@loongson.cn> References: <20231104085755.930439-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8CxbS+UB0ZlmGs5AA--.59322S5 X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ X-Coremail-Antispam: 1Uk129KBj93XoWxJw47Aw4kCr1kZFWfGFW5XFc_yoWruF43pF Z7urn2qw4rXr4UGw1jya1kur45XrWkKr13Xa4kJrWFyrnIyr1YvF4kGF95XFW3J3yIyF1S vryrtw15uF4DAwbCm3ZEXasCq-sJn29KB7ZKAUJUUUU8529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUk2b4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1q6r4UM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12xvs2x26I8E6xACxx 1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1q6rW5McIj6I8E87Iv 67AKxVW8JVWxJwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41l42xK82IYc2 Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s02 6x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_Gr0_Xr1lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE 42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87Iv6x kF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUoxR6UUUUU The vm timer emulation happens in two places, one is during vcpu thread context switch, the other is idle instruction emulation and before entering to guest. SW timer switching is remove during idle instruction emulation, so it is not necessary to disable SW timer before entering to guest. This patch removes SW timer handling before entering guest mode, and put it in HW restore flow when vcpu thread is sched-in. With this patch, vm timer emulation is simpler, there is SW/HW timer switch only in vcpu thread context switch scenario. Signed-off-by: Bibo Mao --- arch/loongarch/include/asm/kvm_vcpu.h | 1 - arch/loongarch/kvm/timer.c | 21 +++++++------------ arch/loongarch/kvm/vcpu.c | 29 --------------------------- 3 files changed, 7 insertions(+), 44 deletions(-) diff --git a/arch/loongarch/include/asm/kvm_vcpu.h b/arch/loongarch/include/asm/kvm_vcpu.h index 553cfa2b2b1c..0e87652f780a 100644 --- a/arch/loongarch/include/asm/kvm_vcpu.h +++ b/arch/loongarch/include/asm/kvm_vcpu.h @@ -55,7 +55,6 @@ void kvm_save_fpu(struct loongarch_fpu *fpu); void kvm_restore_fpu(struct loongarch_fpu *fpu); void kvm_restore_fcsr(struct loongarch_fpu *fpu); -void kvm_acquire_timer(struct kvm_vcpu *vcpu); void kvm_init_timer(struct kvm_vcpu *vcpu, unsigned long hz); void kvm_reset_timer(struct kvm_vcpu *vcpu); void kvm_save_timer(struct kvm_vcpu *vcpu); diff --git a/arch/loongarch/kvm/timer.c b/arch/loongarch/kvm/timer.c index 1d29bd21a9da..45109fa0b299 100644 --- a/arch/loongarch/kvm/timer.c +++ b/arch/loongarch/kvm/timer.c @@ -64,19 +64,6 @@ void kvm_init_timer(struct kvm_vcpu *vcpu, unsigned long timer_hz) kvm_write_sw_gcsr(vcpu->arch.csr, LOONGARCH_CSR_TVAL, 0); } -/* - * Restore hard timer state and enable guest to access timer registers - * without trap, should be called with irq disabled - */ -void kvm_acquire_timer(struct kvm_vcpu *vcpu) -{ - /* - * Freeze the soft-timer and sync the guest stable timer with it. We do - * this with interrupts disabled to avoid latency. - */ - hrtimer_cancel(&vcpu->arch.swtimer); -} - /* * Restore soft timer state from saved context. */ @@ -115,12 +102,18 @@ void kvm_restore_timer(struct kvm_vcpu *vcpu) /* * Inject timer here though sw timer should inject timer * interrupt async already, since sw timer may be cancelled - * during injecting intr async in function kvm_acquire_timer + * during injecting intr async */ kvm_queue_irq(vcpu, INT_TI); } write_gcsr_timertick(delta); + + /* + * Freeze the soft-timer and sync the guest stable timer with it. We do + * this with interrupts disabled to avoid latency. + */ + hrtimer_cancel(&vcpu->arch.swtimer); } /* diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c index 42663a345bd1..cf1c4d64c1b7 100644 --- a/arch/loongarch/kvm/vcpu.c +++ b/arch/loongarch/kvm/vcpu.c @@ -95,7 +95,6 @@ static int kvm_pre_enter_guest(struct kvm_vcpu *vcpu) * check vmid before vcpu enter guest */ local_irq_disable(); - kvm_acquire_timer(vcpu); kvm_deliver_intr(vcpu); kvm_deliver_exception(vcpu); /* Make sure the vcpu mode has been written */ @@ -251,23 +250,6 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, return -EINVAL; } -/** - * kvm_migrate_count() - Migrate timer. - * @vcpu: Virtual CPU. - * - * Migrate hrtimer to the current CPU by cancelling and restarting it - * if the hrtimer is active. - * - * Must be called when the vCPU is migrated to a different CPU, so that - * the timer can interrupt the guest at the new CPU, and the timer irq can - * be delivered to the vCPU. - */ -static void kvm_migrate_count(struct kvm_vcpu *vcpu) -{ - if (hrtimer_cancel(&vcpu->arch.swtimer)) - hrtimer_restart(&vcpu->arch.swtimer); -} - static int _kvm_getcsr(struct kvm_vcpu *vcpu, unsigned int id, u64 *val) { unsigned long gintc; @@ -796,17 +778,6 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) unsigned long flags; local_irq_save(flags); - if (vcpu->arch.last_sched_cpu != cpu) { - kvm_debug("[%d->%d]KVM vCPU[%d] switch\n", - vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id); - /* - * Migrate the timer interrupt to the current CPU so that it - * always interrupts the guest and synchronously triggers a - * guest timer interrupt. - */ - kvm_migrate_count(vcpu); - } - /* Restore guest state to registers */ _kvm_vcpu_load(vcpu, cpu); local_irq_restore(flags);