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authorKyle Meyer <meyerk@hpe.com>2019-08-27 23:43:52 +0200
committerArnaldo Carvalho de Melo <acme@redhat.com>2019-08-29 22:38:32 +0200
commitdf552793493ff83b2b7289389d29d417b3ef6d6d (patch)
tree10cfc2367dad619e22ca34864980a70a28e0d557 /tools/perf/lib/cpumap.c
parentperf header: Replace MAX_NR_CPUS with cpu__max_cpu() (diff)
downloadlinux-df552793493ff83b2b7289389d29d417b3ef6d6d.tar.xz
linux-df552793493ff83b2b7289389d29d417b3ef6d6d.zip
libperf: Warn when exceeding MAX_NR_CPUS in cpumap
Display a warning when attempting to profile more than MAX_NR_CPU CPUs. This patch should not change any behavior. Signed-off-by: Kyle Meyer <kyle.meyer@hpe.com> Reviewed-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <russ.anderson@hpe.com> Link: http://lore.kernel.org/lkml/20190827214352.94272-8-meyerk@stormcage.eag.rdlabs.hpecorp.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to '')
-rw-r--r--tools/perf/lib/cpumap.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/tools/perf/lib/cpumap.c b/tools/perf/lib/cpumap.c
index 2834753576b2..1f0e6f334237 100644
--- a/tools/perf/lib/cpumap.c
+++ b/tools/perf/lib/cpumap.c
@@ -100,6 +100,9 @@ struct perf_cpu_map *perf_cpu_map__read(FILE *file)
if (prev >= 0) {
int new_max = nr_cpus + cpu - prev - 1;
+ WARN_ONCE(new_max >= MAX_NR_CPUS, "Perf can support %d CPUs. "
+ "Consider raising MAX_NR_CPUS\n", MAX_NR_CPUS);
+
if (new_max >= max_entries) {
max_entries = new_max + MAX_NR_CPUS / 2;
tmp = realloc(tmp_cpus, max_entries * sizeof(int));
@@ -192,6 +195,9 @@ struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list)
end_cpu = start_cpu;
}
+ WARN_ONCE(end_cpu >= MAX_NR_CPUS, "Perf can support %d CPUs. "
+ "Consider raising MAX_NR_CPUS\n", MAX_NR_CPUS);
+
for (; start_cpu <= end_cpu; start_cpu++) {
/* check for duplicates */
for (i = 0; i < nr_cpus; i++)