1 files changed, 45 insertions, 0 deletions

diff --git a/tools/perf/arch/powerpc/util/kvm-stat.c b/tools/perf/arch/powerpc/util/kvm-stat.c
index f0dbf7b075c8..9cc1c4a9dec4 100644
--- a/tools/perf/arch/powerpc/util/kvm-stat.c
+++ b/tools/perf/arch/powerpc/util/kvm-stat.c
@@ -5,9 +5,11 @@
 #include "util/debug.h"
 #include "util/evsel.h"
 #include "util/evlist.h"
+#include "util/pmu.h"
 
 #include "book3s_hv_exits.h"
 #include "book3s_hcalls.h"
+#include <subcmd/parse-options.h>
 
 #define NR_TPS 4
 
@@ -172,3 +174,46 @@ int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused)
 
         return ret;
 }
+
+/*
+ * Incase of powerpc architecture, pmu registers are programmable
+ * by guest kernel. So monitoring guest via host may not provide
+ * valid samples with default 'cycles' event. It is better to use
+ * 'trace_imc/trace_cycles' event for guest profiling, since it
+ * can track the guest instruction pointer in the trace-record.
+ *
+ * Function to parse the arguments and return appropriate values.
+ */
+int kvm_add_default_arch_event(int *argc, const char **argv)
+{
+        const char **tmp;
+        bool event = false;
+        int i, j = *argc;
+
+        const struct option event_options[] = {
+                OPT_BOOLEAN('e', "event", &event, NULL),
+                OPT_END()
+        };
+
+        tmp = calloc(j + 1, sizeof(char *));
+        if (!tmp)
+                return -EINVAL;
+
+        for (i = 0; i < j; i++)
+                tmp[i] = argv[i];
+
+        parse_options(j, tmp, event_options, NULL, PARSE_OPT_KEEP_UNKNOWN);
+        if (!event) {
+                if (pmu_have_event("trace_imc", "trace_cycles")) {
+                        argv[j++] = strdup("-e");
+                        argv[j++] = strdup("trace_imc/trace_cycles/");
+                        *argc += 2;
+                } else {
+                        free(tmp);
+                        return -EINVAL;
+                }
+        }
+
+        free(tmp);
+        return 0;
+}