[PATCH v4 20/23] arm64: perf: Count EL2 events if the kernel is running in HYP
From: Will Deacon <hidden>
Date: 2016-02-15 17:22:44
Also in:
kvm, kvmarm, lkml
From: Will Deacon <hidden>
Date: 2016-02-15 17:22:44
Also in:
kvm, kvmarm, lkml
On Thu, Feb 11, 2016 at 06:40:01PM +0000, Marc Zyngier wrote:
When the kernel is running in HYP (with VHE), it is necessary to include EL2 events if the user requests counting kernel or hypervisor events. Reviewed-by: Christoffer Dall <redacted> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <redacted> --- arch/arm64/kernel/perf_event.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c index f7ab14c..6013a38 100644 --- a/arch/arm64/kernel/perf_event.c +++ b/arch/arm64/kernel/perf_event.c@@ -20,6 +20,7 @@ */ #include <asm/irq_regs.h> +#include <asm/virt.h> #include <linux/of.h> #include <linux/perf/arm_pmu.h>@@ -693,10 +694,15 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event, return -EPERM; if (attr->exclude_user) config_base |= ARMV8_EXCLUDE_EL0; - if (attr->exclude_kernel) - config_base |= ARMV8_EXCLUDE_EL1; - if (!attr->exclude_hv) - config_base |= ARMV8_INCLUDE_EL2; + if (is_kernel_in_hyp_mode()) { + if (!attr->exclude_kernel || !attr->exclude_hv) + config_base |= ARMV8_INCLUDE_EL2;
Hmm, so if userspace sets exclude_kernel but not exclude_user and exclude_hv, what should we do? I'm slightly tempted to reject the filter with -EINVAL... Will