Re: [PATCH V2 19/23] libperf evlist: Check nr_mmaps is correct

Ian Rogers
2022-05-06T20:20:48Z

On Fri, May 6, 2022 at 5:26 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> Print an error message if the predetermined number of mmaps is
> incorrect.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>

Acked-by: Ian Rogers <irogers@google.com>

Thanks,
Ian

> ---
> tools/lib/perf/evlist.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
> index eae1f6179dad..f51fdb899d19 100644
> --- a/tools/lib/perf/evlist.c
> +++ b/tools/lib/perf/evlist.c
> @@ -23,6 +23,7 @@
> #include <perf/cpumap.h>
> #include <perf/threadmap.h>
> #include <api/fd/array.h>
> +#include "internal.h"
>
> void perf_evlist__init(struct perf_evlist *evlist)
> {
> @@ -428,7 +429,7 @@ static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_
> static int
> mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
> int idx, struct perf_mmap_param *mp, int cpu_idx,
> - int thread, int *_output, int *_output_overwrite)
> + int thread, int *_output, int *_output_overwrite, int *nr_mmaps)
> {
> struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->all_cpus, cpu_idx);
> struct perf_evsel *evsel;
> @@ -484,6 +485,8 @@ mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
> if (ops->mmap(map, mp, *output, evlist_cpu) < 0)
> return -1;
>
> + *nr_mmaps += 1;
> +
> if (!idx)
> perf_evlist__set_mmap_first(evlist, map, overwrite);
> } else {
> @@ -518,6 +521,7 @@ mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
> {
> int nr_threads = perf_thread_map__nr(evlist->threads);
> int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);
> + int nr_mmaps = 0;
> int cpu, thread;
>
> for (cpu = 0; cpu < nr_cpus; cpu++) {
> @@ -526,11 +530,14 @@ mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
>
> for (thread = 0; thread < nr_threads; thread++) {
> if (mmap_per_evsel(evlist, ops, cpu, mp, cpu,
> - thread, &output, &output_overwrite))
> + thread, &output, &output_overwrite, &nr_mmaps))
> goto out_unmap;
> }
> }
>
> + if (nr_mmaps != evlist->nr_mmaps)
> + pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);
> +
> return 0;
>
> out_unmap:
> --
> 2.25.1
>