4.9-stable review patch. If anyone has any objections, please let me know.
------------------ [ Upstream commit 1497e804d1a6e2bd9107ddf64b0310449f4673eb ] This patch fixes an issue in cpumap.c when used with the TOPOLOGY header. In some configurations, some NUMA nodes may have no CPU (empty cpulist). Yet a cpumap map must be created otherwise perf abort with an error. This patch handles this case by creating a dummy map. Before: $ perf record -o - -e cycles noploop 2 | perf script -i - 0x6e8 [0x6c]: failed to process type: 80 After: $ perf record -o - -e cycles noploop 2 | perf script -i - noploop for 2 seconds Signed-off-by: Stephane Eranian <eran...@google.com> Acked-by: Jiri Olsa <jo...@kernel.org> Cc: Andi Kleen <a...@linux.intel.com> Cc: Kan Liang <kan.li...@linux.intel.com> Cc: Peter Zijlstra <pet...@infradead.org> Link: http://lkml.kernel.org/r/1547885559-1657-1-git-send-email-eran...@google.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> Signed-off-by: Sasha Levin <sas...@kernel.org> --- tools/perf/util/cpumap.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c index 2c0b52264a46..a625cb1500f9 100644 --- a/tools/perf/util/cpumap.c +++ b/tools/perf/util/cpumap.c @@ -129,7 +129,12 @@ struct cpu_map *cpu_map__new(const char *cpu_list) if (!cpu_list) return cpu_map__read_all_cpu_map(); - if (!isdigit(*cpu_list)) + /* + * must handle the case of empty cpumap to cover + * TOPOLOGY header for NUMA nodes with no CPU + * ( e.g., because of CPU hotplug) + */ + if (!isdigit(*cpu_list) && *cpu_list != '\0') goto out; while (isdigit(*cpu_list)) { @@ -176,8 +181,10 @@ struct cpu_map *cpu_map__new(const char *cpu_list) if (nr_cpus > 0) cpus = cpu_map__trim_new(nr_cpus, tmp_cpus); - else + else if (*cpu_list != '\0') cpus = cpu_map__default_new(); + else + cpus = cpu_map__dummy_new(); invalid: free(tmp_cpus); out: -- 2.19.1
