[PATCH V4 2/3] perf,tools: store cpu socket_id and core_id in perf.date

[Kan Liang <kan.liang@intel.com>]

From: Kan Liang <kan.liang@intel.com>

This patch stores cpu socket_id and core_id in perf.date, and read them
to perf_env in header process.
The changes modify the CPU_TOPOLOGY section, but it still keeps backward
compatibility. The patch checks the section size before reading core id
and socket id. It never read data cross the section.
The old perf without this patch can also correctly read the perf.data
from the new perf with this patch. Because the new codes are added at
the end of the cpu_topology section. The old perf can ignore the extra
data.

Examples:

1. New perf with this patch read perf.data from old perf without the
patch.

 $ perf_new report -i perf_old.data --header-only -I
 ......
 # sibling threads : 33
 # sibling threads : 34
 # sibling threads : 35
 # Core ID and Socket ID information is not available
 # node0 meminfo  : total = 32823872 kB, free = 29315548 kB
 # node0 cpu list : 0-17,36-53
 ......

2. Old perf without the patch read perf.data from new perf with the
patch.
 $ perf_old report -i perf_new.data --header-only -I
 ......
 # sibling threads : 33
 # sibling threads : 34
 # sibling threads : 35
 # node0 meminfo  : total = 32823872 kB, free = 29190932 kB
 # node0 cpu list : 0-17,36-53
 ......

3. new perf read the new perf.data

 $ perf_new report -i perf_new.data --header-only -I
 ......
 # sibling threads : 33
 # sibling threads : 34
 # sibling threads : 35
 # CPU 0: Core ID 0, Socket ID 0
 # CPU 1: Core ID 1, Socket ID 0
 ......
 # CPU 61: Core ID 10, Socket ID 1
 # CPU 62: Core ID 11, Socket ID 1
 # CPU 63: Core ID 16, Socket ID 1
 # node0 meminfo  : total = 32823872 kB, free = 29190932 kB
 # node0 cpu list : 0-17,36-53

Signed-off-by: Kan Liang <kan.liang@intel.com>
---
Changes since V1:
 - Store core_id and socket_id in perf.date

Changes since V2:
 - Use funcitons in cpumap.c to get core_id and socket_id
 - Modify changelog

Changes since V3:
 - Improve backward compatibility by checking section size
 - Modify changelog and add some examples

 tools/perf/util/header.c  | 94 ++++++++++++++++++++++++++++++++++++++++++++---
 tools/perf/util/header.h  |  6 +++
 tools/perf/util/session.c |  1 +
 3 files changed, 96 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 4181454..8fd7b7d 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -88,6 +88,9 @@ int write_padded(int fd, const void *bf, size_t count, size_t count_aligned)
 	return err;
 }
 
+#define string_size(str)						\
+	(PERF_ALIGN((strlen(str) + 1), NAME_ALIGN) + sizeof(u32))
+
 static int do_write_string(int fd, const char *str)
 {
 	u32 len, olen;
@@ -441,10 +444,13 @@ static int write_cmdline(int fd, struct perf_header *h __maybe_unused,
 	"/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list"
 
 struct cpu_topo {
+	u32 cpu_nr;
 	u32 core_sib;
 	u32 thread_sib;
 	char **core_siblings;
 	char **thread_siblings;
+	int *core_id;
+	int *phy_pkg_id;
 };
 
 static int build_cpu_topo(struct cpu_topo *tp, int cpu)
@@ -507,6 +513,9 @@ try_threads:
 	}
 	ret = 0;
 done:
+	tp->core_id[cpu] = cpu_map__get_core_id(cpu);
+	tp->phy_pkg_id[cpu] = cpu_map__get_socket_id(cpu);
+
 	if(fp)
 		fclose(fp);
 	free(buf);
@@ -534,7 +543,7 @@ static struct cpu_topo *build_cpu_topology(void)
 	struct cpu_topo *tp;
 	void *addr;
 	u32 nr, i;
-	size_t sz;
+	size_t sz, sz_id;
 	long ncpus;
 	int ret = -1;
 
@@ -545,17 +554,22 @@ static struct cpu_topo *build_cpu_topology(void)
 	nr = (u32)(ncpus & UINT_MAX);
 
 	sz = nr * sizeof(char *);
+	sz_id = nr * sizeof(int);
 
-	addr = calloc(1, sizeof(*tp) + 2 * sz);
+	addr = calloc(1, sizeof(*tp) + 2 * sz + 2 * sz_id);
 	if (!addr)
 		return NULL;
 
 	tp = addr;
-
+	tp->cpu_nr = nr;
 	addr += sizeof(*tp);
 	tp->core_siblings = addr;
 	addr += sz;
 	tp->thread_siblings = addr;
+	addr += sz;
+	tp->core_id = addr;
+	addr += sz_id;
+	tp->phy_pkg_id = addr;
 
 	for (i = 0; i < nr; i++) {
 		ret = build_cpu_topo(tp, i);
@@ -598,6 +612,15 @@ static int write_cpu_topology(int fd, struct perf_header *h __maybe_unused,
 		if (ret < 0)
 			break;
 	}
+
+	for (i = 0; i < tp->cpu_nr; i++) {
+		ret = do_write(fd, &tp->core_id[i], sizeof(int));
+		if (ret < 0)
+			return ret;
+		ret = do_write(fd, &tp->phy_pkg_id[i], sizeof(int));
+		if (ret < 0)
+			return ret;
+	}
 done:
 	free_cpu_topo(tp);
 	return ret;
@@ -938,6 +961,7 @@ static void print_cpu_topology(struct perf_header *ph, int fd __maybe_unused,
 {
 	int nr, i;
 	char *str;
+	int cpu_nr = ph->env.nr_cpus_online;
 
 	nr = ph->env.nr_sibling_cores;
 	str = ph->env.sibling_cores;
@@ -954,6 +978,13 @@ static void print_cpu_topology(struct perf_header *ph, int fd __maybe_unused,
 		fprintf(fp, "# sibling threads : %s\n", str);
 		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");
 }
 
 static void free_event_desc(struct perf_evsel *events)
@@ -1582,7 +1613,7 @@ error:
 	return -1;
 }
 
-static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
+static int process_cpu_topology(struct perf_file_section *section,
 				struct perf_header *ph, int fd,
 				void *data __maybe_unused)
 {
@@ -1590,15 +1621,22 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 	u32 nr, i;
 	char *str;
 	struct strbuf sb;
+	int cpu_nr = ph->env.nr_cpus_online;
+	u64 size = 0;
+
+	ph->env.cpu = calloc(cpu_nr, sizeof(*ph->env.cpu));
+	if (!ph->env.cpu)
+		return -1;
 
 	ret = readn(fd, &nr, sizeof(nr));
 	if (ret != sizeof(nr))
-		return -1;
+		goto free_cpu;
 
 	if (ph->needs_swap)
 		nr = bswap_32(nr);
 
 	ph->env.nr_sibling_cores = nr;
+	size += sizeof(u32);
 	strbuf_init(&sb, 128);
 
 	for (i = 0; i < nr; i++) {
@@ -1608,6 +1646,7 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 
 		/* include a NULL character at the end */
 		strbuf_add(&sb, str, strlen(str) + 1);
+		size += string_size(str);
 		free(str);
 	}
 	ph->env.sibling_cores = strbuf_detach(&sb, NULL);
@@ -1620,6 +1659,7 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 		nr = bswap_32(nr);
 
 	ph->env.nr_sibling_threads = nr;
+	size += sizeof(u32);
 
 	for (i = 0; i < nr; i++) {
 		str = do_read_string(fd, ph);
@@ -1628,13 +1668,57 @@ static int process_cpu_topology(struct perf_file_section *section __maybe_unused
 
 		/* include a NULL character at the end */
 		strbuf_add(&sb, str, strlen(str) + 1);
+		size += string_size(str);
 		free(str);
 	}
 	ph->env.sibling_threads = strbuf_detach(&sb, NULL);
+
+	/*
+	 * The header may be from old perf,
+	 * which doesn't include core id and socket id information.
+	 */
+	if (section->size <= size) {
+		zfree(&ph->env.cpu);
+		return 0;
+	}
+
+	for (i = 0; i < (u32)cpu_nr; i++) {
+		ret = readn(fd, &nr, sizeof(nr));
+		if (ret != sizeof(nr))
+			goto free_cpu;
+
+		if (ph->needs_swap)
+			nr = bswap_32(nr);
+
+		if (nr > (u32)cpu_nr) {
+			pr_debug("core_id number is too big."
+				 "You may need to upgrade the perf tool.\n");
+			goto free_cpu;
+		}
+		ph->env.cpu[i].core_id = nr;
+
+		ret = readn(fd, &nr, sizeof(nr));
+		if (ret != sizeof(nr))
+			goto free_cpu;
+
+		if (ph->needs_swap)
+			nr = bswap_32(nr);
+
+		if (nr > (u32)cpu_nr) {
+			pr_debug("socket_id number is too big."
+				 "You may need to upgrade the perf tool.\n");
+			goto free_cpu;
+		}
+
+		ph->env.cpu[i].socket_id = nr;
+	}
+
 	return 0;
 
 error:
 	strbuf_release(&sb);
+free_cpu:
+	zfree(&ph->env.cpu);
 	return -1;
 }
 
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 396e496..975d803 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -66,6 +66,11 @@ struct perf_header;
 int perf_file_header__read(struct perf_file_header *header,
 			   struct perf_header *ph, int fd);
 
+struct cpu_topology_map {
+	int	socket_id;
+	int	core_id;
+};
+
 struct perf_env {
 	char			*hostname;
 	char			*os_release;
@@ -89,6 +94,7 @@ struct perf_env {
 	char			*sibling_threads;
 	char			*numa_nodes;
 	char			*pmu_mappings;
+	struct cpu_topology_map	*cpu;
 };
 
 struct perf_header {
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 8a4537e..61669be 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -185,6 +185,7 @@ static void perf_session_env__exit(struct perf_env *env)
 	zfree(&env->sibling_threads);
 	zfree(&env->numa_nodes);
 	zfree(&env->pmu_mappings);
+	zfree(&env->cpu);
 }
 
 void perf_session__delete(struct perf_session *session)
-- 
1.8.3.1