diff options
Diffstat (limited to 'tools/perf/arch/x86/util/kvm-stat.c')
| -rw-r--r-- | tools/perf/arch/x86/util/kvm-stat.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/tools/perf/arch/x86/util/kvm-stat.c b/tools/perf/arch/x86/util/kvm-stat.c index 424716518b75..bff36f9345ea 100644 --- a/tools/perf/arch/x86/util/kvm-stat.c +++ b/tools/perf/arch/x86/util/kvm-stat.c @@ -3,9 +3,11 @@ #include <string.h> #include "../../../util/kvm-stat.h" #include "../../../util/evsel.h" +#include "../../../util/env.h" #include <asm/svm.h> #include <asm/vmx.h> #include <asm/kvm.h> +#include <subcmd/parse-options.h> define_exit_reasons_table(vmx_exit_reasons, VMX_EXIT_REASONS); define_exit_reasons_table(svm_exit_reasons, SVM_EXIT_REASONS); @@ -211,3 +213,52 @@ int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid) return 0; } + +/* + * After KVM supports PEBS for guest on Intel platforms + * (https://lore.kernel.org/all/20220411101946.20262-1-likexu@tencent.com/), + * host loses the capability to sample guest with PEBS since all PEBS related + * MSRs are switched to guest value after vm-entry, like IA32_DS_AREA MSR is + * switched to guest GVA at vm-entry. This would lead to "perf kvm record" + * fails to sample guest on Intel platforms since "cycles:P" event is used to + * sample guest by default. + * + * So, to avoid this issue explicitly use "cycles" instead of "cycles:P" event + * by default to sample guest on Intel platforms. + */ +int kvm_add_default_arch_event(int *argc, const char **argv) +{ + const char **tmp; + bool event = false; + int ret = 0, i, j = *argc; + + const struct option event_options[] = { + OPT_BOOLEAN('e', "event", &event, NULL), + OPT_BOOLEAN(0, "pfm-events", &event, NULL), + OPT_END() + }; + + if (!x86__is_intel_cpu()) + return 0; + + tmp = calloc(j + 1, sizeof(char *)); + if (!tmp) + return -ENOMEM; + + for (i = 0; i < j; i++) + tmp[i] = argv[i]; + + parse_options(j, tmp, event_options, NULL, PARSE_OPT_KEEP_UNKNOWN); + if (!event) { + argv[j++] = STRDUP_FAIL_EXIT("-e"); + argv[j++] = STRDUP_FAIL_EXIT("cycles"); + *argc += 2; + } + + free(tmp); + return 0; + +EXIT: + free(tmp); + return ret; +} |