[PATCH 08/47] libperf: Warn when exceeding MAX_NR_CPUS in cpumap
From: Arnaldo Carvalho de Melo <acme@kernel.org>
Date: 2019-09-01 12:24:08
Also in:
lkml
Subsystem:
performance events subsystem, the rest · Maintainers:
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Namhyung Kim, Linus Torvalds
From: Kyle Meyer <redacted> 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 <redacted> 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 (local) Signed-off-by: Arnaldo Carvalho de Melo <redacted> --- tools/perf/lib/cpumap.c | 6 ++++++ 1 file changed, 6 insertions(+)
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++)
--
2.21.0