perf tools: Probe non-deprecated sysfs path 1st

Following Documentation/ABI/stable/sysfs-devices-system-cpu the
/sys/devices/system/cpu/cpuX/topology/core_cpus is deprecated in favor
of thread_siblings, so probe thread_siblings before falling back on
core_cpus.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@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: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20211124001231.3277836-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/smt.c b/tools/perf/util/smt.c
index 2636be6..2b0a36e 100644 (file)
--- a/tools/perf/util/smt.c
+++ b/tools/perf/util/smt.c
@@ -79,11 +79,10 @@ int smt_on(void)
                char fn[256];
 
                snprintf(fn, sizeof fn,
-                       "devices/system/cpu/cpu%d/topology/core_cpus", cpu);
+                       "devices/system/cpu/cpu%d/topology/thread_siblings", cpu);
                if (sysfs__read_str(fn, &str, &strlen) < 0) {
                        snprintf(fn, sizeof fn,
-                               "devices/system/cpu/cpu%d/topology/thread_siblings",
-                               cpu);
+                               "devices/system/cpu/cpu%d/topology/core_cpus", cpu);
                        if (sysfs__read_str(fn, &str, &strlen) < 0)
                                continue;
                }