diff options
Diffstat (limited to 'virt/kvm/arm/pmu.c')
| -rw-r--r-- | virt/kvm/arm/pmu.c | 363 |
1 files changed, 284 insertions, 79 deletions
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index 1c5b76c46e26..3dd8238ed246 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -1,18 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2015 Linaro Ltd. * Author: Shannon Zhao <shannon.zhao@linaro.org> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/cpu.h> @@ -24,29 +13,144 @@ #include <kvm/arm_pmu.h> #include <kvm/arm_vgic.h> +static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx); + +#define PERF_ATTR_CFG1_KVM_PMU_CHAINED 0x1 + /** - * kvm_pmu_get_counter_value - get PMU counter value + * kvm_pmu_idx_is_64bit - determine if select_idx is a 64bit counter * @vcpu: The vcpu pointer * @select_idx: The counter index */ -u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) +static bool kvm_pmu_idx_is_64bit(struct kvm_vcpu *vcpu, u64 select_idx) { - u64 counter, reg, enabled, running; - struct kvm_pmu *pmu = &vcpu->arch.pmu; - struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + return (select_idx == ARMV8_PMU_CYCLE_IDX && + __vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_LC); +} - reg = (select_idx == ARMV8_PMU_CYCLE_IDX) - ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx; - counter = __vcpu_sys_reg(vcpu, reg); +static struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc) +{ + struct kvm_pmu *pmu; + struct kvm_vcpu_arch *vcpu_arch; + + pmc -= pmc->idx; + pmu = container_of(pmc, struct kvm_pmu, pmc[0]); + vcpu_arch = container_of(pmu, struct kvm_vcpu_arch, pmu); + return container_of(vcpu_arch, struct kvm_vcpu, arch); +} + +/** + * kvm_pmu_pmc_is_chained - determine if the pmc is chained + * @pmc: The PMU counter pointer + */ +static bool kvm_pmu_pmc_is_chained(struct kvm_pmc *pmc) +{ + struct kvm_vcpu *vcpu = kvm_pmc_to_vcpu(pmc); + + return test_bit(pmc->idx >> 1, vcpu->arch.pmu.chained); +} + +/** + * kvm_pmu_idx_is_high_counter - determine if select_idx is a high/low counter + * @select_idx: The counter index + */ +static bool kvm_pmu_idx_is_high_counter(u64 select_idx) +{ + return select_idx & 0x1; +} + +/** + * kvm_pmu_get_canonical_pmc - obtain the canonical pmc + * @pmc: The PMU counter pointer + * + * When a pair of PMCs are chained together we use the low counter (canonical) + * to hold the underlying perf event. + */ +static struct kvm_pmc *kvm_pmu_get_canonical_pmc(struct kvm_pmc *pmc) +{ + if (kvm_pmu_pmc_is_chained(pmc) && + kvm_pmu_idx_is_high_counter(pmc->idx)) + return pmc - 1; + + return pmc; +} + +/** + * kvm_pmu_idx_has_chain_evtype - determine if the event type is chain + * @vcpu: The vcpu pointer + * @select_idx: The counter index + */ +static bool kvm_pmu_idx_has_chain_evtype(struct kvm_vcpu *vcpu, u64 select_idx) +{ + u64 eventsel, reg; + + select_idx |= 0x1; + + if (select_idx == ARMV8_PMU_CYCLE_IDX) + return false; + + reg = PMEVTYPER0_EL0 + select_idx; + eventsel = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_EVENT; + + return eventsel == ARMV8_PMUV3_PERFCTR_CHAIN; +} + +/** + * kvm_pmu_get_pair_counter_value - get PMU counter value + * @vcpu: The vcpu pointer + * @pmc: The PMU counter pointer + */ +static u64 kvm_pmu_get_pair_counter_value(struct kvm_vcpu *vcpu, + struct kvm_pmc *pmc) +{ + u64 counter, counter_high, reg, enabled, running; + + if (kvm_pmu_pmc_is_chained(pmc)) { + pmc = kvm_pmu_get_canonical_pmc(pmc); + reg = PMEVCNTR0_EL0 + pmc->idx; + + counter = __vcpu_sys_reg(vcpu, reg); + counter_high = __vcpu_sys_reg(vcpu, reg + 1); + + counter = lower_32_bits(counter) | (counter_high << 32); + } else { + reg = (pmc->idx == ARMV8_PMU_CYCLE_IDX) + ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + pmc->idx; + counter = __vcpu_sys_reg(vcpu, reg); + } - /* The real counter value is equal to the value of counter register plus + /* + * The real counter value is equal to the value of counter register plus * the value perf event counts. */ if (pmc->perf_event) counter += perf_event_read_value(pmc->perf_event, &enabled, &running); - return counter & pmc->bitmask; + return counter; +} + +/** + * kvm_pmu_get_counter_value - get PMU counter value + * @vcpu: The vcpu pointer + * @select_idx: The counter index + */ +u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) +{ + u64 counter; + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + + counter = kvm_pmu_get_pair_counter_value(vcpu, pmc); + + if (kvm_pmu_pmc_is_chained(pmc) && + kvm_pmu_idx_is_high_counter(select_idx)) + counter = upper_32_bits(counter); + + else if (!kvm_pmu_idx_is_64bit(vcpu, select_idx)) + counter = lower_32_bits(counter); + + return counter; } /** @@ -62,6 +166,23 @@ void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val) reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx; __vcpu_sys_reg(vcpu, reg) += (s64)val - kvm_pmu_get_counter_value(vcpu, select_idx); + + /* Recreate the perf event to reflect the updated sample_period */ + kvm_pmu_create_perf_event(vcpu, select_idx); +} + +/** + * kvm_pmu_release_perf_event - remove the perf event + * @pmc: The PMU counter pointer + */ +static void kvm_pmu_release_perf_event(struct kvm_pmc *pmc) +{ + pmc = kvm_pmu_get_canonical_pmc(pmc); + if (pmc->perf_event) { + perf_event_disable(pmc->perf_event); + perf_event_release_kernel(pmc->perf_event); + pmc->perf_event = NULL; + } } /** @@ -74,15 +195,23 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc) { u64 counter, reg; - if (pmc->perf_event) { - counter = kvm_pmu_get_counter_value(vcpu, pmc->idx); + pmc = kvm_pmu_get_canonical_pmc(pmc); + if (!pmc->perf_event) + return; + + counter = kvm_pmu_get_pair_counter_value(vcpu, pmc); + + if (kvm_pmu_pmc_is_chained(pmc)) { + reg = PMEVCNTR0_EL0 + pmc->idx; + __vcpu_sys_reg(vcpu, reg) = lower_32_bits(counter); + __vcpu_sys_reg(vcpu, reg + 1) = upper_32_bits(counter); + } else { reg = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ? PMCCNTR_EL0 : PMEVCNTR0_EL0 + pmc->idx; - __vcpu_sys_reg(vcpu, reg) = counter; - perf_event_disable(pmc->perf_event); - perf_event_release_kernel(pmc->perf_event); - pmc->perf_event = NULL; + __vcpu_sys_reg(vcpu, reg) = lower_32_bits(counter); } + + kvm_pmu_release_perf_event(pmc); } /** @@ -98,8 +227,9 @@ void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) { kvm_pmu_stop_counter(vcpu, &pmu->pmc[i]); pmu->pmc[i].idx = i; - pmu->pmc[i].bitmask = 0xffffffffUL; } + + bitmap_zero(vcpu->arch.pmu.chained, ARMV8_PMU_MAX_COUNTER_PAIRS); } /** @@ -112,15 +242,8 @@ void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; - for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) { - struct kvm_pmc *pmc = &pmu->pmc[i]; - - if (pmc->perf_event) { - perf_event_disable(pmc->perf_event); - perf_event_release_kernel(pmc->perf_event); - pmc->perf_event = NULL; - } - } + for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) + kvm_pmu_release_perf_event(&pmu->pmc[i]); } u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) @@ -135,13 +258,13 @@ u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) } /** - * kvm_pmu_enable_counter - enable selected PMU counter + * kvm_pmu_enable_counter_mask - enable selected PMU counters * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENSET register * * Call perf_event_enable to start counting the perf event */ -void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) +void kvm_pmu_enable_counter_mask(struct kvm_vcpu *vcpu, u64 val) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; @@ -155,6 +278,18 @@ void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) continue; pmc = &pmu->pmc[i]; + + /* + * For high counters of chained events we must recreate the + * perf event with the long (64bit) attribute set. + */ + if (kvm_pmu_pmc_is_chained(pmc) && + kvm_pmu_idx_is_high_counter(i)) { + kvm_pmu_create_perf_event(vcpu, i); + continue; + } + + /* At this point, pmc must be the canonical */ if (pmc->perf_event) { perf_event_enable(pmc->perf_event); if (pmc->perf_event->state != PERF_EVENT_STATE_ACTIVE) @@ -164,13 +299,13 @@ void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val) } /** - * kvm_pmu_disable_counter - disable selected PMU counter + * kvm_pmu_disable_counter_mask - disable selected PMU counters * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENCLR register * * Call perf_event_disable to stop counting the perf event */ -void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) +void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val) { int i; struct kvm_pmu *pmu = &vcpu->arch.pmu; @@ -184,6 +319,18 @@ void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val) continue; pmc = &pmu->pmc[i]; + + /* + * For high counters of chained events we must recreate the + * perf event with the long (64bit) attribute unset. + */ + if (kvm_pmu_pmc_is_chained(pmc) && + kvm_pmu_idx_is_high_counter(i)) { + kvm_pmu_create_perf_event(vcpu, i); + continue; + } + + /* At this point, pmc must be the canonical */ if (pmc->perf_event) perf_event_disable(pmc->perf_event); } @@ -273,17 +420,6 @@ void kvm_pmu_sync_hwstate(struct kvm_vcpu *vcpu) kvm_pmu_update_state(vcpu); } -static inline struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc) -{ - struct kvm_pmu *pmu; - struct kvm_vcpu_arch *vcpu_arch; - - pmc -= pmc->idx; - pmu = container_of(pmc, struct kvm_pmu, pmc[0]); - vcpu_arch = container_of(pmu, struct kvm_vcpu_arch, pmu); - return container_of(vcpu_arch, struct kvm_vcpu, arch); -} - /** * When the perf event overflows, set the overflow status and inform the vcpu. */ @@ -340,17 +476,15 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) */ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) { - struct kvm_pmu *pmu = &vcpu->arch.pmu; - struct kvm_pmc *pmc; u64 mask; int i; mask = kvm_pmu_valid_counter_mask(vcpu); if (val & ARMV8_PMU_PMCR_E) { - kvm_pmu_enable_counter(vcpu, + kvm_pmu_enable_counter_mask(vcpu, __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask); } else { - kvm_pmu_disable_counter(vcpu, mask); + kvm_pmu_disable_counter_mask(vcpu, mask); } if (val & ARMV8_PMU_PMCR_C) @@ -360,11 +494,6 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val) for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++) kvm_pmu_set_counter_value(vcpu, i, 0); } - - if (val & ARMV8_PMU_PMCR_LC) { - pmc = &pmu->pmc[ARMV8_PMU_CYCLE_IDX]; - pmc->bitmask = 0xffffffffffffffffUL; - } } static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx) @@ -374,50 +503,75 @@ static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx) } /** - * kvm_pmu_set_counter_event_type - set selected counter to monitor some event + * kvm_pmu_create_perf_event - create a perf event for a counter * @vcpu: The vcpu pointer - * @data: The data guest writes to PMXEVTYPER_EL0 * @select_idx: The number of selected counter - * - * When OS accesses PMXEVTYPER_EL0, that means it wants to set a PMC to count an - * event with given hardware event number. Here we call perf_event API to - * emulate this action and create a kernel perf event for it. */ -void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, - u64 select_idx) +static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) { struct kvm_pmu *pmu = &vcpu->arch.pmu; - struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + struct kvm_pmc *pmc; struct perf_event *event; struct perf_event_attr attr; - u64 eventsel, counter; + u64 eventsel, counter, reg, data; + + /* + * For chained counters the event type and filtering attributes are + * obtained from the low/even counter. We also use this counter to + * determine if the event is enabled/disabled. + */ + pmc = kvm_pmu_get_canonical_pmc(&pmu->pmc[select_idx]); + + reg = (pmc->idx == ARMV8_PMU_CYCLE_IDX) + ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + pmc->idx; + data = __vcpu_sys_reg(vcpu, reg); kvm_pmu_stop_counter(vcpu, pmc); eventsel = data & ARMV8_PMU_EVTYPE_EVENT; /* Software increment event does't need to be backed by a perf event */ if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR && - select_idx != ARMV8_PMU_CYCLE_IDX) + pmc->idx != ARMV8_PMU_CYCLE_IDX) return; memset(&attr, 0, sizeof(struct perf_event_attr)); attr.type = PERF_TYPE_RAW; attr.size = sizeof(attr); attr.pinned = 1; - attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, select_idx); + attr.disabled = !kvm_pmu_counter_is_enabled(vcpu, pmc->idx); attr.exclude_user = data & ARMV8_PMU_EXCLUDE_EL0 ? 1 : 0; attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0; attr.exclude_hv = 1; /* Don't count EL2 events */ attr.exclude_host = 1; /* Don't count host events */ - attr.config = (select_idx == ARMV8_PMU_CYCLE_IDX) ? + attr.config = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ? ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel; - counter = kvm_pmu_get_counter_value(vcpu, select_idx); - /* The initial sample period (overflow count) of an event. */ - attr.sample_period = (-counter) & pmc->bitmask; + counter = kvm_pmu_get_pair_counter_value(vcpu, pmc); + + if (kvm_pmu_idx_has_chain_evtype(vcpu, pmc->idx)) { + /** + * The initial sample period (overflow count) of an event. For + * chained counters we only support overflow interrupts on the + * high counter. + */ + attr.sample_period = (-counter) & GENMASK(63, 0); + event = perf_event_create_kernel_counter(&attr, -1, current, + kvm_pmu_perf_overflow, + pmc + 1); + + if (kvm_pmu_counter_is_enabled(vcpu, pmc->idx + 1)) + attr.config1 |= PERF_ATTR_CFG1_KVM_PMU_CHAINED; + } else { + /* The initial sample period (overflow count) of an event. */ + if (kvm_pmu_idx_is_64bit(vcpu, pmc->idx)) + attr.sample_period = (-counter) & GENMASK(63, 0); + else + attr.sample_period = (-counter) & GENMASK(31, 0); - event = perf_event_create_kernel_counter(&attr, -1, current, + event = perf_event_create_kernel_counter(&attr, -1, current, kvm_pmu_perf_overflow, pmc); + } + if (IS_ERR(event)) { pr_err_once("kvm: pmu event creation failed %ld\n", PTR_ERR(event)); @@ -427,6 +581,57 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, pmc->perf_event = event; } +/** + * kvm_pmu_update_pmc_chained - update chained bitmap + * @vcpu: The vcpu pointer + * @select_idx: The number of selected counter + * + * Update the chained bitmap based on the event type written in the + * typer register. + */ +static void kvm_pmu_update_pmc_chained(struct kvm_vcpu *vcpu, u64 select_idx) +{ + struct kvm_pmu *pmu = &vcpu->arch.pmu; + struct kvm_pmc *pmc = &pmu->pmc[select_idx]; + + if (kvm_pmu_idx_has_chain_evtype(vcpu, pmc->idx)) { + /* + * During promotion from !chained to chained we must ensure + * the adjacent counter is stopped and its event destroyed + */ + if (!kvm_pmu_pmc_is_chained(pmc)) + kvm_pmu_stop_counter(vcpu, pmc); + + set_bit(pmc->idx >> 1, vcpu->arch.pmu.chained); + } else { + clear_bit(pmc->idx >> 1, vcpu->arch.pmu.chained); + } +} + +/** + * kvm_pmu_set_counter_event_type - set selected counter to monitor some event + * @vcpu: The vcpu pointer + * @data: The data guest writes to PMXEVTYPER_EL0 + * @select_idx: The number of selected counter + * + * When OS accesses PMXEVTYPER_EL0, that means it wants to set a PMC to count an + * event with given hardware event number. Here we call perf_event API to + * emulate this action and create a kernel perf event for it. + */ +void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, + u64 select_idx) +{ + u64 reg, event_type = data & ARMV8_PMU_EVTYPE_MASK; + + reg = (select_idx == ARMV8_PMU_CYCLE_IDX) + ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx; + + __vcpu_sys_reg(vcpu, reg) = event_type; + + kvm_pmu_update_pmc_chained(vcpu, select_idx); + kvm_pmu_create_perf_event(vcpu, select_idx); +} + bool kvm_arm_support_pmu_v3(void) { /* |