perf header: Add die information in CPU topology

With the new CPUID.1F, a new level type of CPU topology, 'die', is
introduced. The 'die' information in CPU topology should be added in
perf header.

To be compatible with old perf.data, the patch checks the section size
before reading the die information. The new info is added at the end of
the cpu_topology section, the old perf tool ignores the extra data.  It
never reads data crossing the section boundary.

The new perf tool with the patch can be used on legacy kernel. Add a new
function has_die_topology() to check if die topology information is
supported by kernel. The function only check X86 and CPU 0. Assuming
other CPUs have same topology.

Use similar method for core and socket to support die id and sibling
dies string.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1559688644-106558-2-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 88 insertions, 6 deletions

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 847ae51a524b..64976254431c 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -599,6 +599,27 @@ static int write_cpu_topology(struct feat_fd *ff,
 		if (ret < 0)
 			return ret;
 	}
+
+	if (!tp->die_sib)
+		goto done;
+
+	ret = do_write(ff, &tp->die_sib, sizeof(tp->die_sib));
+	if (ret < 0)
+		goto done;
+
+	for (i = 0; i < tp->die_sib; i++) {
+		ret = do_write_string(ff, tp->die_siblings[i]);
+		if (ret < 0)
+			goto done;
+	}
+
+	for (j = 0; j < perf_env.nr_cpus_avail; j++) {
+		ret = do_write(ff, &perf_env.cpu[j].die_id,
+			       sizeof(perf_env.cpu[j].die_id));
+		if (ret < 0)
+			return ret;
+	}
+
 done:
 	cpu_topology__delete(tp);
 	return ret;
@@ -1443,6 +1464,16 @@ static void print_cpu_topology(struct feat_fd *ff, FILE *fp)
 		str += strlen(str) + 1;
 	}
 
+	if (ph->env.nr_sibling_dies) {
+		nr = ph->env.nr_sibling_dies;
+		str = ph->env.sibling_dies;
+
+		for (i = 0; i < nr; i++) {
+			fprintf(fp, "# sibling dies    : %s\n", str);
+			str += strlen(str) + 1;
+		}
+	}
+
 	nr = ph->env.nr_sibling_threads;
 	str = ph->env.sibling_threads;
 
@@ -1451,12 +1482,28 @@ static void print_cpu_topology(struct feat_fd *ff, FILE *fp)
 		str += strlen(str) + 1;
 	}
 
-	if (ph->env.cpu != NULL) {
-		for (i = 0; i < cpu_nr; i++)
-			fprintf(fp, "# CPU %d: Core ID %d, Socket ID %d\n", i,
-				ph->env.cpu[i].core_id, ph->env.cpu[i].socket_id);
-	} else
-		fprintf(fp, "# Core ID and Socket ID information is not available\n");
+	if (ph->env.nr_sibling_dies) {
+		if (ph->env.cpu != NULL) {
+			for (i = 0; i < cpu_nr; i++)
+				fprintf(fp, "# CPU %d: Core ID %d, "
+					    "Die ID %d, Socket ID %d\n",
+					    i, ph->env.cpu[i].core_id,
+					    ph->env.cpu[i].die_id,
+					    ph->env.cpu[i].socket_id);
+		} else
+			fprintf(fp, "# Core ID, Die ID and Socket ID "
+				    "information is not available\n");
+	} else {
+		if (ph->env.cpu != NULL) {
+			for (i = 0; i < cpu_nr; i++)
+				fprintf(fp, "# CPU %d: Core ID %d, "
+					    "Socket ID %d\n",
+					    i, ph->env.cpu[i].core_id,
+					    ph->env.cpu[i].socket_id);
+		} else
+			fprintf(fp, "# Core ID and Socket ID "
+				    "information is not available\n");
+	}
 }
 
 static void print_clockid(struct feat_fd *ff, FILE *fp)
@@ -2214,6 +2261,7 @@ static int process_cpu_topology(struct feat_fd *ff, void *data __maybe_unused)
 			goto free_cpu;
 
 		ph->env.cpu[i].core_id = nr;
+		size += sizeof(u32);
 
 		if (do_read_u32(ff, &nr))
 			goto free_cpu;
@@ -2225,6 +2273,40 @@ static int process_cpu_topology(struct feat_fd *ff, void *data __maybe_unused)
 		}
 
 		ph->env.cpu[i].socket_id = nr;
+		size += sizeof(u32);
+	}
+
+	/*
+	 * The header may be from old perf,
+	 * which doesn't include die information.
+	 */
+	if (ff->size <= size)
+		return 0;
+
+	if (do_read_u32(ff, &nr))
+		return -1;
+
+	ph->env.nr_sibling_dies = nr;
+	size += sizeof(u32);
+
+	for (i = 0; i < nr; i++) {
+		str = do_read_string(ff);
+		if (!str)
+			goto error;
+
+		/* include a NULL character at the end */
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
+		size += string_size(str);
+		free(str);
+	}
+	ph->env.sibling_dies = strbuf_detach(&sb, NULL);
+
+	for (i = 0; i < (u32)cpu_nr; i++) {
+		if (do_read_u32(ff, &nr))
+			goto free_cpu;
+
+		ph->env.cpu[i].die_id = nr;
 	}
 
 	return 0;