diff options
Diffstat (limited to 'drivers/perf/arm_pmuv3.c')
| -rw-r--r-- | drivers/perf/arm_pmuv3.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c index c98e4039386d..93b7edb5f1e7 100644 --- a/drivers/perf/arm_pmuv3.c +++ b/drivers/perf/arm_pmuv3.c @@ -677,9 +677,25 @@ static inline u32 armv8pmu_getreset_flags(void) return value; } +static void update_pmuserenr(u64 val) +{ + lockdep_assert_irqs_disabled(); + + /* + * The current PMUSERENR_EL0 value might be the value for the guest. + * If that's the case, have KVM keep tracking of the register value + * for the host EL0 so that KVM can restore it before returning to + * the host EL0. Otherwise, update the register now. + */ + if (kvm_set_pmuserenr(val)) + return; + + write_pmuserenr(val); +} + static void armv8pmu_disable_user_access(void) { - write_pmuserenr(0); + update_pmuserenr(0); } static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu) @@ -695,8 +711,7 @@ static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu) armv8pmu_write_evcntr(i, 0); } - write_pmuserenr(0); - write_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR); + update_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR); } static void armv8pmu_enable_event(struct perf_event *event) |