mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-30 07:34:12 +08:00
96b0eebcc6
Since the reset value of PMCNTENSET and PMCNTENCLR is UNKNOWN, use reset_unknown for its reset handler. Add a handler to emulate writing PMCNTENSET or PMCNTENCLR register. When writing to PMCNTENSET, call perf_event_enable to enable the perf event. When writing to PMCNTENCLR, call perf_event_disable to disable the perf event. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
130 lines
3.4 KiB
C
130 lines
3.4 KiB
C
/*
|
|
* 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>
|
|
#include <linux/kvm.h>
|
|
#include <linux/kvm_host.h>
|
|
#include <linux/perf_event.h>
|
|
#include <asm/kvm_emulate.h>
|
|
#include <kvm/arm_pmu.h>
|
|
|
|
/**
|
|
* 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, reg, enabled, running;
|
|
struct kvm_pmu *pmu = &vcpu->arch.pmu;
|
|
struct kvm_pmc *pmc = &pmu->pmc[select_idx];
|
|
|
|
reg = (select_idx == ARMV8_PMU_CYCLE_IDX)
|
|
? PMCCNTR_EL0 : PMEVCNTR0_EL0 + select_idx;
|
|
counter = vcpu_sys_reg(vcpu, reg);
|
|
|
|
/* 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;
|
|
}
|
|
|
|
/**
|
|
* kvm_pmu_set_counter_value - set PMU counter value
|
|
* @vcpu: The vcpu pointer
|
|
* @select_idx: The counter index
|
|
* @val: The counter value
|
|
*/
|
|
void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val)
|
|
{
|
|
u64 reg;
|
|
|
|
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);
|
|
}
|
|
|
|
u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu)
|
|
{
|
|
u64 val = vcpu_sys_reg(vcpu, PMCR_EL0) >> ARMV8_PMU_PMCR_N_SHIFT;
|
|
|
|
val &= ARMV8_PMU_PMCR_N_MASK;
|
|
if (val == 0)
|
|
return BIT(ARMV8_PMU_CYCLE_IDX);
|
|
else
|
|
return GENMASK(val - 1, 0) | BIT(ARMV8_PMU_CYCLE_IDX);
|
|
}
|
|
|
|
/**
|
|
* kvm_pmu_enable_counter - enable selected PMU counter
|
|
* @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)
|
|
{
|
|
int i;
|
|
struct kvm_pmu *pmu = &vcpu->arch.pmu;
|
|
struct kvm_pmc *pmc;
|
|
|
|
if (!(vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) || !val)
|
|
return;
|
|
|
|
for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) {
|
|
if (!(val & BIT(i)))
|
|
continue;
|
|
|
|
pmc = &pmu->pmc[i];
|
|
if (pmc->perf_event) {
|
|
perf_event_enable(pmc->perf_event);
|
|
if (pmc->perf_event->state != PERF_EVENT_STATE_ACTIVE)
|
|
kvm_debug("fail to enable perf event\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* kvm_pmu_disable_counter - disable selected PMU counter
|
|
* @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)
|
|
{
|
|
int i;
|
|
struct kvm_pmu *pmu = &vcpu->arch.pmu;
|
|
struct kvm_pmc *pmc;
|
|
|
|
if (!val)
|
|
return;
|
|
|
|
for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++) {
|
|
if (!(val & BIT(i)))
|
|
continue;
|
|
|
|
pmc = &pmu->pmc[i];
|
|
if (pmc->perf_event)
|
|
perf_event_disable(pmc->perf_event);
|
|
}
|
|
}
|