Em Wed, Apr 29, 2020 at 07:23:41PM +0300, Konstantin Khlebnikov escreveu: > SMT now could be disabled via "/sys/devices/system/cpu/smt/control". > Status shown in "/sys/devices/system/cpu/smt/active" simply as "0" / "1". > > If this knob isn't here then fallback to checking topology as before.
I've manually applied this one, thanks, please check my perf/core branch later before resending 2/3, thanks. - Arnaldo > Signed-off-by: Konstantin Khlebnikov <[email protected]> > --- > tools/perf/util/smt.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/tools/perf/util/smt.c b/tools/perf/util/smt.c > index dc37b5abd1c3..c398528d1006 100644 > --- a/tools/perf/util/smt.c > +++ b/tools/perf/util/smt.c > @@ -19,6 +19,9 @@ int smt_on(void) > if (cached) > return cached_result; > > + if (sysfs__read_int("devices/system/cpu/smt/active", &active) > 0) > + goto done; > + > ncpu = sysconf(_SC_NPROCESSORS_CONF); > for (cpu = 0; cpu < ncpu; cpu++) { > char fn[256]; > @@ -37,6 +40,7 @@ int smt_on(void) > active = str && (strchr(str, ',') != NULL || strchr(str, '-') != NULL); > free(str); > > +done: > if (!cached) { > cached_result = active; > cached = true; > -- - Arnaldo
