[PATCH v2 2/8] perf cputopo: Update to use pakage_cpus

From: Ian Rogers
Date: Wed Nov 10 2021 - 19:21:26 EST


core_siblings_list is the deprecated topology name for
package_cpus_list, update the code to try the non-deprecated path first.
Adjust variable names to match topology name.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/cputopo.c | 26 ++++++++++++++++----------
tools/perf/util/cputopo.h | 11 +++++++++--
tools/perf/util/header.c | 6 +++---
3 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/tools/perf/util/cputopo.c b/tools/perf/util/cputopo.c
index ec77e2a7b3ca..f72a7de19e02 100644
--- a/tools/perf/util/cputopo.c
+++ b/tools/perf/util/cputopo.c
@@ -14,7 +14,9 @@
#include "env.h"
#include "pmu-hybrid.h"

-#define CORE_SIB_FMT \
+#define PACKAGE_CPUS_FMT \
+ "%s/devices/system/cpu/cpu%d/topology/package_cpus_list"
+#define PACKAGE_CPUS_FMT_OLD \
"%s/devices/system/cpu/cpu%d/topology/core_siblings_list"
#define DIE_SIB_FMT \
"%s/devices/system/cpu/cpu%d/topology/die_cpus_list"
@@ -39,8 +41,12 @@ static int build_cpu_topology(struct cpu_topology *tp, int cpu)
u32 i = 0;
int ret = -1;

- scnprintf(filename, MAXPATHLEN, CORE_SIB_FMT,
+ scnprintf(filename, MAXPATHLEN, PACKAGE_CPUS_FMT,
sysfs__mountpoint(), cpu);
+ if (access(filename, F_OK) == -1) {
+ scnprintf(filename, MAXPATHLEN, PACKAGE_CPUS_FMT_OLD,
+ sysfs__mountpoint(), cpu);
+ }
fp = fopen(filename, "r");
if (!fp)
goto try_dies;
@@ -54,13 +60,13 @@ static int build_cpu_topology(struct cpu_topology *tp, int cpu)
if (p)
*p = '\0';

- for (i = 0; i < tp->core_sib; i++) {
- if (!strcmp(buf, tp->core_siblings[i]))
+ for (i = 0; i < tp->package_cpus_lists; i++) {
+ if (!strcmp(buf, tp->package_cpus_list[i]))
break;
}
- if (i == tp->core_sib) {
- tp->core_siblings[i] = buf;
- tp->core_sib++;
+ if (i == tp->package_cpus_lists) {
+ tp->package_cpus_list[i] = buf;
+ tp->package_cpus_lists++;
buf = NULL;
len = 0;
}
@@ -139,8 +145,8 @@ void cpu_topology__delete(struct cpu_topology *tp)
if (!tp)
return;

- for (i = 0 ; i < tp->core_sib; i++)
- zfree(&tp->core_siblings[i]);
+ for (i = 0 ; i < tp->package_cpus_lists; i++)
+ zfree(&tp->package_cpus_list[i]);

if (tp->die_sib) {
for (i = 0 ; i < tp->die_sib; i++)
@@ -205,7 +211,7 @@ struct cpu_topology *cpu_topology__new(void)

tp = addr;
addr += sizeof(*tp);
- tp->core_siblings = addr;
+ tp->package_cpus_list = addr;
addr += sz;
if (has_die) {
tp->die_siblings = addr;
diff --git a/tools/perf/util/cputopo.h b/tools/perf/util/cputopo.h
index d9af97177068..4ec9cb192c3d 100644
--- a/tools/perf/util/cputopo.h
+++ b/tools/perf/util/cputopo.h
@@ -5,10 +5,17 @@
#include <linux/types.h>

struct cpu_topology {
- u32 core_sib;
+ /* The number of unique package_cpus_lists below. */
+ u32 package_cpus_lists;
u32 die_sib;
u32 thread_sib;
- char **core_siblings;
+ /*
+ * An array of strings where each string is unique and read from
+ * /sys/devices/system/cpu/cpuX/topology/package_cpus_list. From the ABI
+ * each of these is a human-readable list of CPUs sharing the same
+ * physical_package_id. The format is like 0-3, 8-11, 14,17.
+ */
+ const char **package_cpus_list;
char **die_siblings;
char **thread_siblings;
};
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 56511db8fa03..4e89cd35345b 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -583,12 +583,12 @@ static int write_cpu_topology(struct feat_fd *ff,
if (!tp)
return -1;

- ret = do_write(ff, &tp->core_sib, sizeof(tp->core_sib));
+ ret = do_write(ff, &tp->package_cpus_lists, sizeof(tp->package_cpus_lists));
if (ret < 0)
goto done;

- for (i = 0; i < tp->core_sib; i++) {
- ret = do_write_string(ff, tp->core_siblings[i]);
+ for (i = 0; i < tp->package_cpus_lists; i++) {
+ ret = do_write_string(ff, tp->package_cpus_list[i]);
if (ret < 0)
goto done;
}
--
2.34.0.rc1.387.gb447b232ab-goog