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 4D05AC43334 for ; Fri, 22 Jul 2022 16:51:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235877AbiGVQvR (ORCPT ); Fri, 22 Jul 2022 12:51:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235961AbiGVQvB (ORCPT ); Fri, 22 Jul 2022 12:51:01 -0400 Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8F6C6468 for ; Fri, 22 Jul 2022 09:51:00 -0700 (PDT) Received: by mail-pj1-x1029.google.com with SMTP id pc13so4855965pjb.4 for ; Fri, 22 Jul 2022 09:51:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20210112.gappssmtp.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=KXvEKspdEkxNZ7tN6bENVdCw8YU5lf4YyaP929zXWIY=; b=7p+lThfs8k+oMeRhSJ4+Sa0GbYsf5NGzgVNLIZsOK/i7bYyR9ikCF+F4K2laR6bTve 6F2xKPhOVzVlntVsPYc1gdJ2wtZzASEPN4YRBYwW2gSZ+jP+i31xDUywHBLquGkotWp1 9eC11EYlLNS2YYteaIEbi0Q0sdeseQNurVzM7efF5pLBCGBzPP4ZU2aH23vi4raqmKv3 RWcDot9rNBkQwxfarCY6J9JMfjUXnXV9LpwB7QNZjtfBLdFyppIzuxUTWRG7E5vGEYCe KkS3CaND5njvc/9QX5tYNJwuYu6py/U1L7f4O6IhAtsivG1ChTMKyANICi3Hff5mA7gx DcyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=KXvEKspdEkxNZ7tN6bENVdCw8YU5lf4YyaP929zXWIY=; b=wfrTDO5Z9rFTrc1owdsG7kgN1QYfU+gzDePS/ce6LDGa8IdtF4G+JV/MOCHAoTx38o WMuF+PzRI7Xxq5YD31z7qqimvocidK1MmJD/GxADMZnFXWm8qG9AFxavWrMEznqTxItr dmY94Lwr6CHszvqjKVZ6MWzVXWZVoulsQjhXuTYzQZsUURn7fRF4tTa/A5p67+HIDPay d78n1OJMG5xOzvyZOmjdbWAn0cK34EgaOkB3Qfs8pHx1hiP8qWzB9jfmIJnZJf4Uo6wC enqLa2atX7duZn8on7N9KM7wt6cHN2+ZmaBQw+xM4SBSIZFPl8JXUZkULJTNcTVW4jlA E8rw== X-Gm-Message-State: AJIora8zvNPP5Zj1cuCRtV2kPCLhObsCXmwTMB9riTHJ0qDwwl8gH5VY iVLH0KkB5tmzRK8d+5lvF/Js7Rog4CSFNg== X-Google-Smtp-Source: AGRyM1tUVg7Oh9vy5jlPMjPGaMSlVSCY+jB3RipEuR8oPEj5J52fy13dYqMdBlfpR+3cY+bINis72g== X-Received: by 2002:a17:90b:390a:b0:1f0:6a1a:9654 with SMTP id ob10-20020a17090b390a00b001f06a1a9654mr564533pjb.90.1658508659995; Fri, 22 Jul 2022 09:50:59 -0700 (PDT) Received: from atishp.ba.rivosinc.com ([66.220.2.162]) by smtp.gmail.com with ESMTPSA id s7-20020a170902ea0700b0016a3f9e4865sm4028476plg.148.2022.07.22.09.50.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 22 Jul 2022 09:50:59 -0700 (PDT) From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Anup Patel , Albert Ou , Atish Patra , Daniel Lezcano , Guo Ren , Heiko Stuebner , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , Paolo Bonzini , Paul Walmsley , Rob Herring , Thomas Gleixner , Tsukasa OI , Wei Fu Subject: [PATCH v7 4/4] RISC-V: KVM: Support sstc extension Date: Fri, 22 Jul 2022 09:50:47 -0700 Message-Id: <20220722165047.519994-5-atishp@rivosinc.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220722165047.519994-1-atishp@rivosinc.com> References: <20220722165047.519994-1-atishp@rivosinc.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel Signed-off-by: Atish Patra --- arch/riscv/include/asm/kvm_vcpu_timer.h | 7 ++ arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu.c | 8 +- arch/riscv/kvm/vcpu_timer.c | 144 +++++++++++++++++++++++- 4 files changed, 153 insertions(+), 7 deletions(-) diff --git a/arch/riscv/include/asm/kvm_vcpu_timer.h b/arch/riscv/include/asm/kvm_vcpu_timer.h index 50138e2eb91b..0d8fdb8ec63a 100644 --- a/arch/riscv/include/asm/kvm_vcpu_timer.h +++ b/arch/riscv/include/asm/kvm_vcpu_timer.h @@ -28,6 +28,11 @@ struct kvm_vcpu_timer { u64 next_cycles; /* Underlying hrtimer instance */ struct hrtimer hrt; + + /* Flag to check if sstc is enabled or not */ + bool sstc_enabled; + /* A function pointer to switch between stimecmp or hrtimer at runtime */ + int (*timer_next_event)(struct kvm_vcpu *vcpu, u64 ncycles); }; int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles); @@ -40,5 +45,7 @@ int kvm_riscv_vcpu_timer_deinit(struct kvm_vcpu *vcpu); int kvm_riscv_vcpu_timer_reset(struct kvm_vcpu *vcpu); void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu); void kvm_riscv_guest_timer_init(struct kvm *kvm); +void kvm_riscv_vcpu_timer_save(struct kvm_vcpu *vcpu); +bool kvm_riscv_vcpu_timer_pending(struct kvm_vcpu *vcpu); #endif diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 24b2a6e27698..7351417afd62 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -97,6 +97,7 @@ enum KVM_RISCV_ISA_EXT_ID { KVM_RISCV_ISA_EXT_I, KVM_RISCV_ISA_EXT_M, KVM_RISCV_ISA_EXT_SVPBMT, + KVM_RISCV_ISA_EXT_SSTC, KVM_RISCV_ISA_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index 5d271b597613..d0f08d5b4282 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -52,6 +52,7 @@ static const unsigned long kvm_isa_ext_arr[] = { RISCV_ISA_EXT_i, RISCV_ISA_EXT_m, RISCV_ISA_EXT_SVPBMT, + RISCV_ISA_EXT_SSTC, }; static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext) @@ -85,6 +86,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext) case KVM_RISCV_ISA_EXT_C: case KVM_RISCV_ISA_EXT_I: case KVM_RISCV_ISA_EXT_M: + case KVM_RISCV_ISA_EXT_SSTC: return false; default: break; @@ -203,7 +205,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) { - return kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER); + return kvm_riscv_vcpu_timer_pending(vcpu); } void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) @@ -785,6 +787,8 @@ static void kvm_riscv_vcpu_update_config(const unsigned long *isa) if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SVPBMT)) henvcfg |= ENVCFG_PBMTE; + if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SSTC)) + henvcfg |= ENVCFG_STCE; csr_write(CSR_HENVCFG, henvcfg); #ifdef CONFIG_32BIT csr_write(CSR_HENVCFGH, henvcfg >> 32); @@ -828,6 +832,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) vcpu->arch.isa); kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); + kvm_riscv_vcpu_timer_save(vcpu); + csr->vsstatus = csr_read(CSR_VSSTATUS); csr->vsie = csr_read(CSR_VSIE); csr->vstvec = csr_read(CSR_VSTVEC); diff --git a/arch/riscv/kvm/vcpu_timer.c b/arch/riscv/kvm/vcpu_timer.c index 595043857049..16f50c46ba39 100644 --- a/arch/riscv/kvm/vcpu_timer.c +++ b/arch/riscv/kvm/vcpu_timer.c @@ -69,7 +69,18 @@ static int kvm_riscv_vcpu_timer_cancel(struct kvm_vcpu_timer *t) return 0; } -int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) +static int kvm_riscv_vcpu_update_vstimecmp(struct kvm_vcpu *vcpu, u64 ncycles) +{ +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, ncycles & 0xFFFFFFFF); + csr_write(CSR_VSTIMECMPH, ncycles >> 32); +#else + csr_write(CSR_VSTIMECMP, ncycles); +#endif + return 0; +} + +static int kvm_riscv_vcpu_update_hrtimer(struct kvm_vcpu *vcpu, u64 ncycles) { struct kvm_vcpu_timer *t = &vcpu->arch.timer; struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; @@ -88,6 +99,65 @@ int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) return 0; } +int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + return t->timer_next_event(vcpu, ncycles); +} + +static enum hrtimer_restart kvm_riscv_vcpu_vstimer_expired(struct hrtimer *h) +{ + u64 delta_ns; + struct kvm_vcpu_timer *t = container_of(h, struct kvm_vcpu_timer, hrt); + struct kvm_vcpu *vcpu = container_of(t, struct kvm_vcpu, arch.timer); + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (kvm_riscv_current_cycles(gt) < t->next_cycles) { + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + hrtimer_forward_now(&t->hrt, ktime_set(0, delta_ns)); + return HRTIMER_RESTART; + } + + t->next_set = false; + kvm_vcpu_kick(vcpu); + + return HRTIMER_NORESTART; +} + +bool kvm_riscv_vcpu_timer_pending(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (!kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t) || + kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER)) + return true; + else + return false; +} + +static void kvm_riscv_vcpu_timer_blocking(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 delta_ns; + + if (!t->init_done) + return; + + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + if (delta_ns) { + hrtimer_start(&t->hrt, ktime_set(0, delta_ns), HRTIMER_MODE_REL); + t->next_set = true; + } +} + +static void kvm_riscv_vcpu_timer_unblocking(struct kvm_vcpu *vcpu) +{ + kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); +} + int kvm_riscv_vcpu_get_reg_timer(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) { @@ -180,10 +250,20 @@ int kvm_riscv_vcpu_timer_init(struct kvm_vcpu *vcpu) return -EINVAL; hrtimer_init(&t->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - t->hrt.function = kvm_riscv_vcpu_hrtimer_expired; t->init_done = true; t->next_set = false; + /* Enable sstc for every vcpu if available in hardware */ + if (riscv_isa_extension_available(NULL, SSTC)) { + t->sstc_enabled = true; + t->hrt.function = kvm_riscv_vcpu_vstimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_vstimecmp; + } else { + t->sstc_enabled = false; + t->hrt.function = kvm_riscv_vcpu_hrtimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_hrtimer; + } + return 0; } @@ -199,21 +279,73 @@ int kvm_riscv_vcpu_timer_deinit(struct kvm_vcpu *vcpu) int kvm_riscv_vcpu_timer_reset(struct kvm_vcpu *vcpu) { + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + t->next_cycles = -1ULL; return kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); } -void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu) +static void kvm_riscv_vcpu_update_timedelta(struct kvm_vcpu *vcpu) { struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; -#ifdef CONFIG_64BIT - csr_write(CSR_HTIMEDELTA, gt->time_delta); -#else +#if defined(CONFIG_32BIT) csr_write(CSR_HTIMEDELTA, (u32)(gt->time_delta)); csr_write(CSR_HTIMEDELTAH, (u32)(gt->time_delta >> 32)); +#else + csr_write(CSR_HTIMEDELTA, gt->time_delta); #endif } +void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr; + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + kvm_riscv_vcpu_update_timedelta(vcpu); + + if (!t->sstc_enabled) + return; + + csr = &vcpu->arch.guest_csr; +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, (u32)t->next_cycles); + csr_write(CSR_VSTIMECMPH, (u32)(t->next_cycles >> 32)); +#else + csr_write(CSR_VSTIMECMP, t->next_cycles); +#endif + + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + kvm_riscv_vcpu_timer_unblocking(vcpu); +} + +void kvm_riscv_vcpu_timer_save(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr; + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + if (!t->sstc_enabled) + return; + + csr = &vcpu->arch.guest_csr; + t = &vcpu->arch.timer; +#if defined(CONFIG_32BIT) + t->next_cycles = csr_read(CSR_VSTIMECMP); + t->next_cycles |= (u64)csr_read(CSR_VSTIMECMPH) << 32; +#else + t->next_cycles = csr_read(CSR_VSTIMECMP); +#endif + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + if (kvm_vcpu_is_blocking(vcpu)) + kvm_riscv_vcpu_timer_blocking(vcpu); +} + void kvm_riscv_guest_timer_init(struct kvm *kvm) { struct kvm_guest_timer *gt = &kvm->arch.timer; -- 2.25.1 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 02E2DCCA473 for ; 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Fri, 22 Jul 2022 09:50:59 -0700 (PDT) From: Atish Patra To: linux-kernel@vger.kernel.org Cc: Atish Patra , Anup Patel , Albert Ou , Atish Patra , Daniel Lezcano , Guo Ren , Heiko Stuebner , kvm-riscv@lists.infradead.org, kvm@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , Paolo Bonzini , Paul Walmsley , Rob Herring , Thomas Gleixner , Tsukasa OI , Wei Fu Subject: [PATCH v7 4/4] RISC-V: KVM: Support sstc extension Date: Fri, 22 Jul 2022 09:50:47 -0700 Message-Id: <20220722165047.519994-5-atishp@rivosinc.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220722165047.519994-1-atishp@rivosinc.com> References: <20220722165047.519994-1-atishp@rivosinc.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220722_095101_791716_BB4BE0C2 X-CRM114-Status: GOOD ( 19.56 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel Signed-off-by: Atish Patra --- arch/riscv/include/asm/kvm_vcpu_timer.h | 7 ++ arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu.c | 8 +- arch/riscv/kvm/vcpu_timer.c | 144 +++++++++++++++++++++++- 4 files changed, 153 insertions(+), 7 deletions(-) diff --git a/arch/riscv/include/asm/kvm_vcpu_timer.h b/arch/riscv/include/asm/kvm_vcpu_timer.h index 50138e2eb91b..0d8fdb8ec63a 100644 --- a/arch/riscv/include/asm/kvm_vcpu_timer.h +++ b/arch/riscv/include/asm/kvm_vcpu_timer.h @@ -28,6 +28,11 @@ struct kvm_vcpu_timer { u64 next_cycles; /* Underlying hrtimer instance */ struct hrtimer hrt; + + /* Flag to check if sstc is enabled or not */ + bool sstc_enabled; + /* A function pointer to switch between stimecmp or hrtimer at runtime */ + int (*timer_next_event)(struct kvm_vcpu *vcpu, u64 ncycles); }; int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles); @@ -40,5 +45,7 @@ int kvm_riscv_vcpu_timer_deinit(struct kvm_vcpu *vcpu); int kvm_riscv_vcpu_timer_reset(struct kvm_vcpu *vcpu); void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu); void kvm_riscv_guest_timer_init(struct kvm *kvm); +void kvm_riscv_vcpu_timer_save(struct kvm_vcpu *vcpu); +bool kvm_riscv_vcpu_timer_pending(struct kvm_vcpu *vcpu); #endif diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 24b2a6e27698..7351417afd62 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -97,6 +97,7 @@ enum KVM_RISCV_ISA_EXT_ID { KVM_RISCV_ISA_EXT_I, KVM_RISCV_ISA_EXT_M, KVM_RISCV_ISA_EXT_SVPBMT, + KVM_RISCV_ISA_EXT_SSTC, KVM_RISCV_ISA_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index 5d271b597613..d0f08d5b4282 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -52,6 +52,7 @@ static const unsigned long kvm_isa_ext_arr[] = { RISCV_ISA_EXT_i, RISCV_ISA_EXT_m, RISCV_ISA_EXT_SVPBMT, + RISCV_ISA_EXT_SSTC, }; static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext) @@ -85,6 +86,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext) case KVM_RISCV_ISA_EXT_C: case KVM_RISCV_ISA_EXT_I: case KVM_RISCV_ISA_EXT_M: + case KVM_RISCV_ISA_EXT_SSTC: return false; default: break; @@ -203,7 +205,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) { - return kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER); + return kvm_riscv_vcpu_timer_pending(vcpu); } void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) @@ -785,6 +787,8 @@ static void kvm_riscv_vcpu_update_config(const unsigned long *isa) if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SVPBMT)) henvcfg |= ENVCFG_PBMTE; + if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SSTC)) + henvcfg |= ENVCFG_STCE; csr_write(CSR_HENVCFG, henvcfg); #ifdef CONFIG_32BIT csr_write(CSR_HENVCFGH, henvcfg >> 32); @@ -828,6 +832,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) vcpu->arch.isa); kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); + kvm_riscv_vcpu_timer_save(vcpu); + csr->vsstatus = csr_read(CSR_VSSTATUS); csr->vsie = csr_read(CSR_VSIE); csr->vstvec = csr_read(CSR_VSTVEC); diff --git a/arch/riscv/kvm/vcpu_timer.c b/arch/riscv/kvm/vcpu_timer.c index 595043857049..16f50c46ba39 100644 --- a/arch/riscv/kvm/vcpu_timer.c +++ b/arch/riscv/kvm/vcpu_timer.c @@ -69,7 +69,18 @@ static int kvm_riscv_vcpu_timer_cancel(struct kvm_vcpu_timer *t) return 0; } -int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) +static int kvm_riscv_vcpu_update_vstimecmp(struct kvm_vcpu *vcpu, u64 ncycles) +{ +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, ncycles & 0xFFFFFFFF); + csr_write(CSR_VSTIMECMPH, ncycles >> 32); +#else + csr_write(CSR_VSTIMECMP, ncycles); +#endif + return 0; +} + +static int kvm_riscv_vcpu_update_hrtimer(struct kvm_vcpu *vcpu, u64 ncycles) { struct kvm_vcpu_timer *t = &vcpu->arch.timer; struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; @@ -88,6 +99,65 @@ int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) return 0; } +int kvm_riscv_vcpu_timer_next_event(struct kvm_vcpu *vcpu, u64 ncycles) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + return t->timer_next_event(vcpu, ncycles); +} + +static enum hrtimer_restart kvm_riscv_vcpu_vstimer_expired(struct hrtimer *h) +{ + u64 delta_ns; + struct kvm_vcpu_timer *t = container_of(h, struct kvm_vcpu_timer, hrt); + struct kvm_vcpu *vcpu = container_of(t, struct kvm_vcpu, arch.timer); + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (kvm_riscv_current_cycles(gt) < t->next_cycles) { + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + hrtimer_forward_now(&t->hrt, ktime_set(0, delta_ns)); + return HRTIMER_RESTART; + } + + t->next_set = false; + kvm_vcpu_kick(vcpu); + + return HRTIMER_NORESTART; +} + +bool kvm_riscv_vcpu_timer_pending(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + + if (!kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t) || + kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER)) + return true; + else + return false; +} + +static void kvm_riscv_vcpu_timer_blocking(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; + u64 delta_ns; + + if (!t->init_done) + return; + + delta_ns = kvm_riscv_delta_cycles2ns(t->next_cycles, gt, t); + if (delta_ns) { + hrtimer_start(&t->hrt, ktime_set(0, delta_ns), HRTIMER_MODE_REL); + t->next_set = true; + } +} + +static void kvm_riscv_vcpu_timer_unblocking(struct kvm_vcpu *vcpu) +{ + kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); +} + int kvm_riscv_vcpu_get_reg_timer(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) { @@ -180,10 +250,20 @@ int kvm_riscv_vcpu_timer_init(struct kvm_vcpu *vcpu) return -EINVAL; hrtimer_init(&t->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - t->hrt.function = kvm_riscv_vcpu_hrtimer_expired; t->init_done = true; t->next_set = false; + /* Enable sstc for every vcpu if available in hardware */ + if (riscv_isa_extension_available(NULL, SSTC)) { + t->sstc_enabled = true; + t->hrt.function = kvm_riscv_vcpu_vstimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_vstimecmp; + } else { + t->sstc_enabled = false; + t->hrt.function = kvm_riscv_vcpu_hrtimer_expired; + t->timer_next_event = kvm_riscv_vcpu_update_hrtimer; + } + return 0; } @@ -199,21 +279,73 @@ int kvm_riscv_vcpu_timer_deinit(struct kvm_vcpu *vcpu) int kvm_riscv_vcpu_timer_reset(struct kvm_vcpu *vcpu) { + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + t->next_cycles = -1ULL; return kvm_riscv_vcpu_timer_cancel(&vcpu->arch.timer); } -void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu) +static void kvm_riscv_vcpu_update_timedelta(struct kvm_vcpu *vcpu) { struct kvm_guest_timer *gt = &vcpu->kvm->arch.timer; -#ifdef CONFIG_64BIT - csr_write(CSR_HTIMEDELTA, gt->time_delta); -#else +#if defined(CONFIG_32BIT) csr_write(CSR_HTIMEDELTA, (u32)(gt->time_delta)); csr_write(CSR_HTIMEDELTAH, (u32)(gt->time_delta >> 32)); +#else + csr_write(CSR_HTIMEDELTA, gt->time_delta); #endif } +void kvm_riscv_vcpu_timer_restore(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr; + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + kvm_riscv_vcpu_update_timedelta(vcpu); + + if (!t->sstc_enabled) + return; + + csr = &vcpu->arch.guest_csr; +#if defined(CONFIG_32BIT) + csr_write(CSR_VSTIMECMP, (u32)t->next_cycles); + csr_write(CSR_VSTIMECMPH, (u32)(t->next_cycles >> 32)); +#else + csr_write(CSR_VSTIMECMP, t->next_cycles); +#endif + + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + kvm_riscv_vcpu_timer_unblocking(vcpu); +} + +void kvm_riscv_vcpu_timer_save(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr; + struct kvm_vcpu_timer *t = &vcpu->arch.timer; + + if (!t->sstc_enabled) + return; + + csr = &vcpu->arch.guest_csr; + t = &vcpu->arch.timer; +#if defined(CONFIG_32BIT) + t->next_cycles = csr_read(CSR_VSTIMECMP); + t->next_cycles |= (u64)csr_read(CSR_VSTIMECMPH) << 32; +#else + t->next_cycles = csr_read(CSR_VSTIMECMP); +#endif + /* timer should be enabled for the remaining operations */ + if (unlikely(!t->init_done)) + return; + + if (kvm_vcpu_is_blocking(vcpu)) + kvm_riscv_vcpu_timer_blocking(vcpu); +} + void kvm_riscv_guest_timer_init(struct kvm *kvm) { struct kvm_guest_timer *gt = &kvm->arch.timer; -- 2.25.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv