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

From: Adrian Hunter
Date: Fri May 06 2022 - 08:28:08 EST


Print an error message if the predetermined number of mmaps is
incorrect.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
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