From: Ian Rogers irogers@google.com
commit 4ffbe87e2d5b53bcb0213d8650bbe70bf942de6a upstream.
sysfs__read_int() returns 0 on success, and so the fast read path was always failing.
Fixes: bb629484d924118e ("perf tools: Simplify checking if SMT is active.") Signed-off-by: Ian Rogers irogers@google.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Andi Kleen ak@linux.intel.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: http://lore.kernel.org/lkml/20211124001231.3277836-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/util/smt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/perf/util/smt.c +++ b/tools/perf/util/smt.c @@ -15,7 +15,7 @@ int smt_on(void) if (cached) return cached_result;
- if (sysfs__read_int("devices/system/cpu/smt/active", &cached_result) > 0) + if (sysfs__read_int("devices/system/cpu/smt/active", &cached_result) >= 0) goto done;
ncpu = sysconf(_SC_NPROCESSORS_CONF);