diff options
Diffstat (limited to 'src/cpu')
| -rw-r--r-- | src/cpu/kvm/base.cc | 12 | ||||
| -rw-r--r-- | src/cpu/kvm/perfevent.hh | 35 |
2 files changed, 47 insertions, 0 deletions
diff --git a/src/cpu/kvm/base.cc b/src/cpu/kvm/base.cc index a8e115da7..d25e145a5 100644 --- a/src/cpu/kvm/base.cc +++ b/src/cpu/kvm/base.cc @@ -1133,6 +1133,12 @@ BaseKvmCPU::setupCounters() cfgCycles.disabled(true) .pinned(true); + // Try to exclude the host. We set both exclude_hv and + // exclude_host since different architectures use slightly + // different APIs in the kernel. + cfgCycles.exclude_hv(true) + .exclude_host(true); + if (perfControlledByTimer) { // We need to configure the cycles counter to send overflows // since we are going to use it to trigger timer signals that @@ -1206,6 +1212,12 @@ BaseKvmCPU::setupInstCounter(uint64_t period) PerfKvmCounterConfig cfgInstructions(PERF_TYPE_HARDWARE, PERF_COUNT_HW_INSTRUCTIONS); + // Try to exclude the host. We set both exclude_hv and + // exclude_host since different architectures use slightly + // different APIs in the kernel. + cfgInstructions.exclude_hv(true) + .exclude_host(true); + if (period) { // Setup a sampling counter if that has been requested. cfgInstructions.wakeupEvents(1) diff --git a/src/cpu/kvm/perfevent.hh b/src/cpu/kvm/perfevent.hh index eed900994..b1b0da283 100644 --- a/src/cpu/kvm/perfevent.hh +++ b/src/cpu/kvm/perfevent.hh @@ -45,6 +45,8 @@ #include <inttypes.h> +#include "config/have_perf_attr_exclude_host.hh" + /** * PerfEvent counter configuration. */ @@ -125,6 +127,39 @@ class PerfKvmCounterConfig return *this; } + /** + * Exclude the events from the host (i.e., only include events + * from the guest system). + * + * Intel CPUs seem to support this attribute from Linux 3.2 and + * onwards. Non-x86 architectures currently ignore this attribute + * (Linux 3.12-rc5). + * + * @warn This attribute is ignored if it isn't present in the + * kernel headers or if the kernel doesn't support it. + * + * @param val true to exclude host events + */ + PerfKvmCounterConfig &exclude_host(bool val) { +#if HAVE_PERF_ATTR_EXCLUDE_HOST == 1 + attr.exclude_host = val; +#endif + return *this; + } + + /** + * Exclude the hyper visor (i.e., only include events from the + * guest system). + * + * @warn This is attribute only seems to be ignored on Intel. + * + * @param val true to exclude host events + */ + PerfKvmCounterConfig &exclude_hv(bool val) { + attr.exclude_hv = val; + return *this; + } + /** Underlying perf_event_attr structure describing the counter */ struct perf_event_attr attr; }; |