[PATCH V1 19/23] libperf evlist: Check nr_mmaps is correct

From: Adrian Hunter <adrian.hunter@intel.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>, Ian Rogers <irogers@google.com>,
	Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>,
	Namhyung Kim <namhyung@kernel.org>, Leo Yan <leo.yan@linaro.org>,
	linux-kernel@vger.kernel.org
Subject: [PATCH V1 19/23] libperf evlist: Check nr_mmaps is correct
Date: Thu,  5 May 2022 19:56:35 +0300	[thread overview]
Message-ID: <20220505165639.361733-20-adrian.hunter@intel.com> (raw)
In-Reply-To: <20220505165639.361733-1-adrian.hunter@intel.com>

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

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 tools/lib/perf/evlist.c                | 11 +++++++++--
 tools/lib/perf/include/internal/mmap.h |  5 +++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
index 0acf43946479..8a82b4b94b99 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)
 {
@@ -424,7 +425,7 @@ 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;
@@ -480,6 +481,8 @@ 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 {
@@ -514,6 +517,7 @@ 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++) {
@@ -522,11 +526,14 @@ 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:
diff --git a/tools/lib/perf/include/internal/mmap.h b/tools/lib/perf/include/internal/mmap.h
index 5a062af8e9d8..9b00828e70ef 100644
--- a/tools/lib/perf/include/internal/mmap.h
+++ b/tools/lib/perf/include/internal/mmap.h
@@ -56,4 +56,9 @@ u64 perf_mmap__read_head(struct perf_mmap *map);
 
 int perf_mmap__read_self(struct perf_mmap *map, struct perf_counts_values *count);
 
+static inline bool perf_mmap__is_mmapped(struct perf_mmap *map)
+{
+	return map->base;
+}
+
 #endif /* __LIBPERF_INTERNAL_MMAP_H */
-- 
2.25.1

