diff options
Diffstat (limited to 'tools/perf/util/evlist.c')
| -rw-r--r-- | tools/perf/util/evlist.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 68c1f9546650..b1cea711232b 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -812,6 +812,7 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx, int fd; int cpu; + mp->prot = PROT_READ | PROT_WRITE; if (evsel->attr.write_backward) { output = _output_backward; maps = evlist->backward_mmap; @@ -824,6 +825,7 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx, if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY) perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING); } + mp->prot &= ~PROT_WRITE; } if (evsel->system_wide && thread) @@ -1058,9 +1060,12 @@ int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages, struct perf_evsel *evsel; const struct cpu_map *cpus = evlist->cpus; const struct thread_map *threads = evlist->threads; - struct mmap_params mp = { - .prot = PROT_READ | PROT_WRITE, - }; + /* + * Delay setting mp.prot: set it before calling perf_mmap__mmap. + * Its value is decided by evsel's write_backward. + * So &mp should not be passed through const pointer. + */ + struct mmap_params mp; if (!evlist->mmap) evlist->mmap = perf_evlist__alloc_mmap(evlist); |