1 files changed, 78 insertions, 0 deletions

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 69374deeb4a8..63aad3109e34 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -20,6 +20,7 @@
 #include "symbol.h"
 #include "debug.h"
 #include "cpumap.h"
+#include "pmu.h"
 
 static bool no_buildid_cache = false;
 
@@ -1004,6 +1005,45 @@ done:
 }
 
 /*
+ * File format:
+ *
+ * struct pmu_mappings {
+ *	u32	pmu_num;
+ *	struct pmu_map {
+ *		u32	type;
+ *		char	name[];
+ *	}[pmu_num];
+ * };
+ */
+
+static int write_pmu_mappings(int fd, struct perf_header *h __used,
+			      struct perf_evlist *evlist __used)
+{
+	struct perf_pmu *pmu = NULL;
+	off_t offset = lseek(fd, 0, SEEK_CUR);
+	__u32 pmu_num = 0;
+
+	/* write real pmu_num later */
+	do_write(fd, &pmu_num, sizeof(pmu_num));
+
+	while ((pmu = perf_pmu__scan(pmu))) {
+		if (!pmu->name)
+			continue;
+		pmu_num++;
+		do_write(fd, &pmu->type, sizeof(pmu->type));
+		do_write_string(fd, pmu->name);
+	}
+
+	if (pwrite(fd, &pmu_num, sizeof(pmu_num), offset) != sizeof(pmu_num)) {
+		/* discard all */
+		lseek(fd, offset, SEEK_SET);
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
  * default get_cpuid(): nothing gets recorded
  * actual implementation must be in arch/$(ARCH)/util/header.c
  */
@@ -1389,6 +1429,43 @@ static void print_branch_stack(struct perf_header *ph __used, int fd __used,
 	fprintf(fp, "# contains samples with branch stack\n");
 }
 
+static void print_pmu_mappings(struct perf_header *ph, int fd, FILE *fp)
+{
+	const char *delimiter = "# pmu mappings: ";
+	char *name;
+	int ret;
+	u32 pmu_num;
+	u32 type;
+
+	ret = read(fd, &pmu_num, sizeof(pmu_num));
+	if (ret != sizeof(pmu_num))
+		goto error;
+
+	if (!pmu_num) {
+		fprintf(fp, "# pmu mappings: not available\n");
+		return;
+	}
+
+	while (pmu_num) {
+		if (read(fd, &type, sizeof(type)) != sizeof(type))
+			break;
+		name = do_read_string(fd, ph);
+		if (!name)
+			break;
+		pmu_num--;
+		fprintf(fp, "%s%s = %" PRIu32, delimiter, name, type);
+		free(name);
+		delimiter = ", ";
+	}
+
+	fprintf(fp, "\n");
+
+	if (!pmu_num)
+		return;
+error:
+	fprintf(fp, "# pmu mappings: unable to read\n");
+}
+
 static int __event_process_build_id(struct build_id_event *bev,
 				    char *filename,
 				    struct perf_session *session)
@@ -1644,6 +1721,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
 	FEAT_OPF(HEADER_CPU_TOPOLOGY,	cpu_topology),
 	FEAT_OPF(HEADER_NUMA_TOPOLOGY,	numa_topology),
 	FEAT_OPA(HEADER_BRANCH_STACK,	branch_stack),
+	FEAT_OPA(HEADER_PMU_MAPPINGS,	pmu_mappings),
 };
 
 struct header_print_data {