4.19-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit e34c940245437f36d2c492edd1f8237eff391064 ] Ravi Bangoria reported that we fail with an empty NUMA node with the following message: $ lscpu NUMA node0 CPU(s): NUMA node1 CPU(s): 0-4 $ sudo ./perf c2c report node/cpu topology bugFailed setup nodes Fix this by detecting the empty node and keeping its CPU set empty. Reported-by: Nageswara R Sastry <nasastry@xxxxxxxxxx> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx> Tested-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Jonas Rabenstein <jonas.rabenstein@xxxxxxxxxxxxxxxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20190305152536.21035-2-jolsa@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/builtin-c2c.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c index f3aa9d02a5ab..763c2edf52e7 100644 --- a/tools/perf/builtin-c2c.c +++ b/tools/perf/builtin-c2c.c @@ -2055,6 +2055,12 @@ static int setup_nodes(struct perf_session *session) if (!set) return -ENOMEM; + nodes[node] = set; + + /* empty node, skip */ + if (cpu_map__empty(map)) + continue; + for (cpu = 0; cpu < map->nr; cpu++) { set_bit(map->map[cpu], set); @@ -2063,8 +2069,6 @@ static int setup_nodes(struct perf_session *session) cpu2node[map->map[cpu]] = node; } - - nodes[node] = set; } setup_nodes_header(); -- 2.19.1
