diff options
Diffstat (limited to 'tools/perf/builtin-report.c')
| -rw-r--r-- | tools/perf/builtin-report.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index 498c6f70a74..287a173523a 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -116,6 +116,9 @@ static int process_sample_event(union perf_event *event, if (al.filtered || (hide_unresolved && al.sym == NULL)) return 0; + if (al.map != NULL) + al.map->dso->hit = 1; + if (perf_session__add_hist_entry(session, &al, sample, evsel)) { pr_debug("problem incrementing symbol period, skipping event\n"); return -1; @@ -249,6 +252,8 @@ static int __cmd_report(void) u64 nr_samples; struct perf_session *session; struct perf_evsel *pos; + struct map *kernel_map; + struct kmap *kernel_kmap; const char *help = "For a higher level overview, try: perf report --sort comm,dso"; signal(SIGINT, sig_handler); @@ -268,6 +273,24 @@ static int __cmd_report(void) if (ret) goto out_delete; + kernel_map = session->host_machine.vmlinux_maps[MAP__FUNCTION]; + kernel_kmap = map__kmap(kernel_map); + if (kernel_map == NULL || + (kernel_map->dso->hit && + (kernel_kmap->ref_reloc_sym == NULL || + kernel_kmap->ref_reloc_sym->addr == 0))) { + const struct dso *kdso = kernel_map->dso; + + ui__warning( +"Kernel address maps (/proc/{kallsyms,modules}) were restricted.\n\n" +"Check /proc/sys/kernel/kptr_restrict before running 'perf record'.\n\n%s\n\n" +"Samples in kernel modules can't be resolved as well.\n\n", + RB_EMPTY_ROOT(&kdso->symbols[MAP__FUNCTION]) ? +"As no suitable kallsyms nor vmlinux was found, kernel samples\n" +"can't be resolved." : +"If some relocation was applied (e.g. kexec) symbols may be misresolved."); + } + if (dump_trace) { perf_session__fprintf_nr_events(session, stdout); goto out_delete; |