On Mon, Oct 19, 2020 at 08:36:13AM +0800, Leo Yan wrote: > Some archs (e.g. x86 and Arm64) don't enable the configuration > CONFIG_MEMORY_HOTPLUG by default, if this configuration is not enabled > when build the kernel image, the SysFS for memory nodes will be missed. > This results in perf tool has no chance to catpure the memory nodes > information, when perf tool reports the result and detects no memory > nodes, it outputs "assertion failed at util/mem2node.c:99". > > The output log doesn't give out reason for the failure and users have no > clue for how to fix it. This patch changes to use explicit way for > warning: it tells user that detected no memory nodes and suggests to > enable CONFIG_MEMORY_HOTPLUG for kernel building. > > Signed-off-by: Leo Yan <leo....@linaro.org>
Acked-by: Jiri Olsa <jo...@redhat.com> thanks, jirka > --- > tools/perf/util/mem2node.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/mem2node.c b/tools/perf/util/mem2node.c > index c84f5841c7ab..03a7d7b27737 100644 > --- a/tools/perf/util/mem2node.c > +++ b/tools/perf/util/mem2node.c > @@ -96,7 +96,8 @@ int mem2node__init(struct mem2node *map, struct perf_env > *env) > > /* Cut unused entries, due to merging. */ > tmp_entries = realloc(entries, sizeof(*entries) * j); > - if (tmp_entries || WARN_ON_ONCE(j == 0)) > + if (tmp_entries || > + WARN_ONCE(j == 0, "No memory nodes, is CONFIG_MEMORY_HOTPLUG > enabled?\n")) > entries = tmp_entries; > > for (i = 0; i < j; i++) { > -- > 2.17.1 >