1 files changed, 18 insertions, 15 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4e75583ddd6d..564491fa18b2 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -197,7 +197,7 @@ static void sig_atexit(void)
         if (child_pid > 0)
                 kill(child_pid, SIGTERM);
 
-        if (signr == -1)
+        if (signr == -1 || signr == SIGUSR1)
                 return;
 
         signal(signr, SIG_DFL);
@@ -515,6 +515,7 @@ static int __cmd_record(int argc, const char **argv)
         atexit(sig_atexit);
         signal(SIGCHLD, sig_handler);
         signal(SIGINT, sig_handler);
+        signal(SIGUSR1, sig_handler);
 
         if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) {
                 perror("failed to create pipes");
@@ -606,6 +607,7 @@ static int __cmd_record(int argc, const char **argv)
                         execvp(argv[0], (char **)argv);
 
                         perror(argv[0]);
+                        kill(getppid(), SIGUSR1);
                         exit(-1);
                 }
 
@@ -697,17 +699,18 @@ static int __cmd_record(int argc, const char **argv)
         if (err < 0)
                 err = event__synthesize_kernel_mmap(process_synthesized_event,
                                                     session, machine, "_stext");
-        if (err < 0) {
-                pr_err("Couldn't record kernel reference relocation symbol.\n");
-                return err;
-        }
+        if (err < 0)
+                pr_err("Couldn't record kernel reference relocation symbol\n"
+                       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
+                       "Check /proc/kallsyms permission or run as root.\n");
 
         err = event__synthesize_modules(process_synthesized_event,
                                         session, machine);
-        if (err < 0) {
-                pr_err("Couldn't record kernel reference relocation symbol.\n");
-                return err;
-        }
+        if (err < 0)
+                pr_err("Couldn't record kernel module information.\n"
+                       "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
+                       "Check /proc/modules permission or run as root.\n");
+
         if (perf_guest)
                 perf_session__process_machines(session, event__synthesize_guest_os);
 
@@ -761,7 +764,7 @@ static int __cmd_record(int argc, const char **argv)
                 }
         }
 
-        if (quiet)
+        if (quiet || signr == SIGUSR1)
                 return 0;
 
         fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
@@ -790,7 +793,7 @@ static const char * const record_usage[] = {
 
 static bool force, append_file;
 
-static const struct option options[] = {
+const struct option record_options[] = {
         OPT_CALLBACK('e', "event", NULL, "event",
                      "event selector. use 'perf list' to list available events",
                      parse_events),
@@ -839,16 +842,16 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
 {
         int i, j, err = -ENOMEM;
 
-        argc = parse_options(argc, argv, options, record_usage,
+        argc = parse_options(argc, argv, record_options, record_usage,
                             PARSE_OPT_STOP_AT_NON_OPTION);
         if (!argc && target_pid == -1 && target_tid == -1 &&
                 !system_wide && !cpu_list)
-                usage_with_options(record_usage, options);
+                usage_with_options(record_usage, record_options);
 
         if (force && append_file) {
                 fprintf(stderr, "Can't overwrite and append at the same time."
                                 " You need to choose between -f and -A");
-                usage_with_options(record_usage, options);
+                usage_with_options(record_usage, record_options);
         } else if (append_file) {
                 write_mode = WRITE_APPEND;
         } else {
@@ -871,7 +874,7 @@ int cmd_record(int argc, const char **argv, const char *prefix __used)
                 if (thread_num <= 0) {
                         fprintf(stderr, "Can't find all threads of pid %d\n",
                                         target_pid);
-                        usage_with_options(record_usage, options);
+                        usage_with_options(record_usage, record_options);
                 }
         } else {
                 all_tids=malloc(sizeof(pid_t));