perf cputopo: Match thread_siblings to topology ABI name

The topology name for thread_siblings is core_cpus_list, use this for
consistency and add documentation.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul A . Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <song@kernel.org>
Cc: Wan Jiabing <wanjiabing@vivo.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20211111002109.194172-5-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/cputopo.c

@@ -20,10 +20,10 @@
 	"%s/devices/system/cpu/cpu%d/topology/core_siblings_list"
 #define DIE_CPUS_FMT \
 	"%s/devices/system/cpu/cpu%d/topology/die_cpus_list"
-#define THRD_SIB_FMT \
-	"%s/devices/system/cpu/cpu%d/topology/thread_siblings_list"
-#define THRD_SIB_FMT_NEW \
+#define CORE_CPUS_FMT \
 	"%s/devices/system/cpu/cpu%d/topology/core_cpus_list"
+#define CORE_CPUS_FMT_OLD \
+	"%s/devices/system/cpu/cpu%d/topology/thread_siblings_list"
 #define NODE_ONLINE_FMT \
 	"%s/devices/system/node/online"
 #define NODE_MEMINFO_FMT \
@@ -104,10 +104,10 @@ try_dies:
 	ret = 0;
 
 try_threads:
-	scnprintf(filename, MAXPATHLEN, THRD_SIB_FMT_NEW,
+	scnprintf(filename, MAXPATHLEN, CORE_CPUS_FMT,
 		  sysfs__mountpoint(), cpu);
 	if (access(filename, F_OK) == -1) {
-		scnprintf(filename, MAXPATHLEN, THRD_SIB_FMT,
+		scnprintf(filename, MAXPATHLEN, CORE_CPUS_FMT_OLD,
 			  sysfs__mountpoint(), cpu);
 	}
 	fp = fopen(filename, "r");
@@ -121,13 +121,13 @@ try_threads:
 	if (p)
 		*p = '\0';
 
-	for (i = 0; i < tp->thread_sib; i++) {
-		if (!strcmp(buf, tp->thread_siblings[i]))
+	for (i = 0; i < tp->core_cpus_lists; i++) {
+		if (!strcmp(buf, tp->core_cpus_list[i]))
 			break;
 	}
-	if (i == tp->thread_sib) {
-		tp->thread_siblings[i] = buf;
-		tp->thread_sib++;
+	if (i == tp->core_cpus_lists) {
+		tp->core_cpus_list[i] = buf;
+		tp->core_cpus_lists++;
 		buf = NULL;
 	}
 	ret = 0;
@@ -151,8 +151,8 @@ void cpu_topology__delete(struct cpu_topology *tp)
 	for (i = 0 ; i < tp->die_cpus_lists; i++)
 		zfree(&tp->die_cpus_list[i]);
 
-	for (i = 0 ; i < tp->thread_sib; i++)
-		zfree(&tp->thread_siblings[i]);
+	for (i = 0 ; i < tp->core_cpus_lists; i++)
+		zfree(&tp->core_cpus_list[i]);
 
 	free(tp);
 }
@@ -215,7 +215,7 @@ struct cpu_topology *cpu_topology__new(void)
 		tp->die_cpus_list = addr;
 		addr += sz;
 	}
-	tp->thread_siblings = addr;
+	tp->core_cpus_list = addr;
 
 	for (i = 0; i < nr; i++) {
 		if (!cpu_map__has(map, i))

tools/perf/util/cputopo.h

@@ -9,7 +9,8 @@ struct cpu_topology {
 	u32	  package_cpus_lists;
 	/* The number of unique die_cpu_lists below. */
 	u32	  die_cpus_lists;
-	u32	  thread_sib;
+	/* The number of unique core_cpu_lists below. */
+	u32	  core_cpus_lists;
 	/*
 	 * An array of strings where each string is unique and read from
 	 * /sys/devices/system/cpu/cpuX/topology/package_cpus_list. From the ABI
@@ -24,7 +25,13 @@ struct cpu_topology {
 	 * The format is like 0-3, 8-11, 14,17.
 	 */
 	const char **die_cpus_list;
-	char	**thread_siblings;
+	/*
+	 * An array of string where each string is unique and from
+	 * /sys/devices/system/cpu/cpuX/topology/core_cpus_list. From the ABI
+	 * each of these is a human-readable list of CPUs within the same
+	 * core. The format is like 0-3, 8-11, 14,17.
+	 */
+	const char **core_cpus_list;
 };
 
 struct numa_topology_node {

tools/perf/util/header.c

@@ -592,12 +592,12 @@ static int write_cpu_topology(struct feat_fd *ff,
 		if (ret < 0)
 			goto done;
 	}
-	ret = do_write(ff, &tp->thread_sib, sizeof(tp->thread_sib));
+	ret = do_write(ff, &tp->core_cpus_lists, sizeof(tp->core_cpus_lists));
 	if (ret < 0)
 		goto done;
 
-	for (i = 0; i < tp->thread_sib; i++) {
-		ret = do_write_string(ff, tp->thread_siblings[i]);
+	for (i = 0; i < tp->core_cpus_lists; i++) {
+		ret = do_write_string(ff, tp->core_cpus_list[i]);
 		if (ret < 0)
 			break;
 	}