trace-cmd/report: Add --kallsyms to insert function list

If for some reason a trace.dat file is missing the function list
(sometimes happens when creating a trace.dat from restore), add
away to allow trace-cmd report to pull in a kallsyms file to
use instead.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 44 insertions, 0 deletions

diff --git a/trace-read.c b/trace-read.c
index 15284f5..326054e 100644
--- a/trace-read.c
+++ b/trace-read.c
@@ -679,10 +679,47 @@ static void add_cpu(const char *cpu_str)
                 __add_cpu(cpu);
 }
 
+static void read_file_fd(int fd, char *dst, int len)
+{
+        size_t size = 0;
+        int r;
+
+        do {
+                r = read(fd, dst+size, len);
+                if (r > 0) {
+                        size += r;
+                        len -= r;
+                }
+        } while (r > 0);
+}
+
+static void add_functions(struct pevent *pevent, const char *file)
+{
+        struct stat st;
+        char *buf;
+        int ret;
+        int fd;
+
+        fd = open(file, O_RDONLY);
+        if (fd < 0)
+                die("Can't read file %s", file);
+
+        ret = fstat(fd, &st);
+        if (ret < 0)
+                die("Can't stat file %s", file);
+
+        buf = malloc_or_die(st.st_size);
+        read_file_fd(fd, buf, st.st_size);
+        close(fd);
+        parse_proc_kallsyms(pevent, buf, st.st_size);
+        free(buf);
+}
+
 void trace_report (int argc, char **argv)
 {
         struct tracecmd_input *handle;
         struct pevent *pevent;
+        const char *functions = NULL;
         int show_funcs = 0;
         int show_endian = 0;
         int show_page_size = 0;
@@ -709,6 +746,7 @@ void trace_report (int argc, char **argv)
                         {"cpu", required_argument, NULL, 0},
                         {"events", no_argument, NULL, 0},
                         {"filter-test", no_argument, NULL, 'T'},
+                        {"kallsyms", required_argument, NULL, 0},
                         {"help", no_argument, NULL, '?'},
                         {NULL, 0, NULL, 0}
                 };
@@ -785,6 +823,9 @@ void trace_report (int argc, char **argv)
                         case 2: /* filter-test */
                                 test_filters = 1;
                                 break;
+                        case 3: /* kallsyms */
+                                functions = optarg;
+                                break;
                         default:
                                 usage(argv);
                         }
@@ -824,6 +865,9 @@ void trace_report (int argc, char **argv)
         if (test_filters)
                 pevent->test_filters = 1;
 
+        if (functions)
+                add_functions(pevent, functions);
+
         if (show_endian) {
                 printf("file is %s endian and host is %s endian\n",
                        pevent_is_file_bigendian(pevent) ? "big" : "little",