perf mem-events: Avoid uninitialized read

[ Upstream commit 85f73c377b2ac9988a204b119aebb33ca5c60083 ]

pmu should be initialized to NULL before perf_pmus__scan loop. Fix and
shrink the scope of pmu at the same time. Issue detected by clang-tidy.

Fixes: 5752c20f3787 ("perf mem: Scan all PMUs instead of just core ones")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: llvm@lists.linux.dev
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Tom Rix <trix@redhat.com>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20231009183920.200859-10-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index 39ffe8c..954b235 100644 (file)
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -185,7 +185,6 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
 {
        int i = *argv_nr, k = 0;
        struct perf_mem_event *e;
-       struct perf_pmu *pmu;
 
        for (int j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
                e = perf_mem_events__ptr(j);
@@ -202,6 +201,8 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
                        rec_argv[i++] = "-e";
                        rec_argv[i++] = perf_mem_events__name(j, NULL);
                } else {
+                       struct perf_pmu *pmu = NULL;
+
                        if (!e->supported) {
                                perf_mem_events__print_unsupport_hybrid(e, j);
                                return -1;