perf trace/scripting: List available scripts

Lists the available perf trace scripts, one per line e.g.:

root@tropicana:~# perf trace -l
List of available trace scripts:
  workqueue-stats                      workqueue stats (ins/exe/create/destroy)
  wakeup-latency                       system-wide min/max/avg wakeup latency
  rw-by-file <comm>                    r/w activity for a program, by file
  check-perf-trace                     useless but exhaustive test script
  rw-by-pid                            system-wide r/w activity

To be consistent with the other listing options in perf, the
current latency trace option was changed to '-L', and '-l' is
now used to access the script listing as:

To create the list, it searches each scripts/*/bin directory for
files ending with "-report" and reads information found in
certain comment lines contained in those shell scripts:

  - if the comment line starts with "description:", the rest of the
    line is used as a 'half-line' description.  To keep each line in
    the list to a single line, the description should be limited to 40
    characters (the rest of the line contains the script name and
    args)

  - if the comment line starts with "args:", the rest of the line
    names the args the script supports.  Required args should be
    surrounded by <> brackets, optional args by [] brackets.

The current scripts in scripts/perl/bin have also been updated
with description: and args: comments.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
LKML-Reference: <1260867220-15699-5-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 198 insertions, 1 deletions

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 88b0353d4019..7674153c4bbe 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -274,6 +274,201 @@ static int parse_scriptname(const struct option *opt __used,
         return 0;
 }
 
+#define for_each_lang(scripts_dir, lang_dirent, lang_next)              \
+        while (!readdir_r(scripts_dir, &lang_dirent, &lang_next) &&     \
+               lang_next)                                               \
+                if (lang_dirent.d_type == DT_DIR &&                     \
+                    (strcmp(lang_dirent.d_name, ".")) &&                \
+                    (strcmp(lang_dirent.d_name, "..")))
+
+#define for_each_script(lang_dir, script_dirent, script_next)           \
+        while (!readdir_r(lang_dir, &script_dirent, &script_next) &&    \
+               script_next)                                             \
+                if (script_dirent.d_type != DT_DIR)
+
+
+#define RECORD_SUFFIX                   "-record"
+#define REPORT_SUFFIX                   "-report"
+
+struct script_desc {
+        struct list_head        node;
+        char                    *name;
+        char                    *half_liner;
+        char                    *args;
+};
+
+LIST_HEAD(script_descs);
+
+static struct script_desc *script_desc__new(const char *name)
+{
+        struct script_desc *s = zalloc(sizeof(*s));
+
+        if (s != NULL)
+                s->name = strdup(name);
+
+        return s;
+}
+
+static void script_desc__delete(struct script_desc *s)
+{
+        free(s->name);
+        free(s);
+}
+
+static void script_desc__add(struct script_desc *s)
+{
+        list_add_tail(&s->node, &script_descs);
+}
+
+static struct script_desc *script_desc__find(const char *name)
+{
+        struct script_desc *s;
+
+        list_for_each_entry(s, &script_descs, node)
+                if (strcasecmp(s->name, name) == 0)
+                        return s;
+        return NULL;
+}
+
+static struct script_desc *script_desc__findnew(const char *name)
+{
+        struct script_desc *s = script_desc__find(name);
+
+        if (s)
+                return s;
+
+        s = script_desc__new(name);
+        if (!s)
+                goto out_delete_desc;
+
+        script_desc__add(s);
+
+        return s;
+
+out_delete_desc:
+        script_desc__delete(s);
+
+        return NULL;
+}
+
+static char *ends_with(char *str, const char *suffix)
+{
+        size_t suffix_len = strlen(suffix);
+        char *p = str;
+
+        if (strlen(str) > suffix_len) {
+                p = str + strlen(str) - suffix_len;
+                if (!strncmp(p, suffix, suffix_len))
+                        return p;
+        }
+
+        return NULL;
+}
+
+static char *ltrim(char *str)
+{
+        int len = strlen(str);
+
+        while (len && isspace(*str)) {
+                len--;
+                str++;
+        }
+
+        return str;
+}
+
+static int read_script_info(struct script_desc *desc, const char *filename)
+{
+        char line[BUFSIZ], *p;
+        FILE *fp;
+
+        fp = fopen(filename, "r");
+        if (!fp)
+                return -1;
+
+        while (fgets(line, sizeof(line), fp)) {
+                p = ltrim(line);
+                if (strlen(p) == 0)
+                        continue;
+                if (*p != '#')
+                        continue;
+                p++;
+                if (strlen(p) && *p == '!')
+                        continue;
+
+                p = ltrim(p);
+                if (strlen(p) && p[strlen(p) - 1] == '\n')
+                        p[strlen(p) - 1] = '\0';
+
+                if (!strncmp(p, "description:", strlen("description:"))) {
+                        p += strlen("description:");
+                        desc->half_liner = strdup(ltrim(p));
+                        continue;
+                }
+
+                if (!strncmp(p, "args:", strlen("args:"))) {
+                        p += strlen("args:");
+                        desc->args = strdup(ltrim(p));
+                        continue;
+                }
+        }
+
+        fclose(fp);
+
+        return 0;
+}
+
+static int list_available_scripts(const struct option *opt __used,
+                                  const char *s __used, int unset __used)
+{
+        struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
+        char scripts_path[MAXPATHLEN];
+        DIR *scripts_dir, *lang_dir;
+        char script_path[MAXPATHLEN];
+        char lang_path[MAXPATHLEN];
+        struct script_desc *desc;
+        char first_half[BUFSIZ];
+        char *script_root;
+        char *str;
+
+        snprintf(scripts_path, MAXPATHLEN, "%s/scripts", perf_exec_path());
+
+        scripts_dir = opendir(scripts_path);
+        if (!scripts_dir)
+                return -1;
+
+        for_each_lang(scripts_dir, lang_dirent, lang_next) {
+                snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
+                         lang_dirent.d_name);
+                lang_dir = opendir(lang_path);
+                if (!lang_dir)
+                        continue;
+
+                for_each_script(lang_dir, script_dirent, script_next) {
+                        script_root = strdup(script_dirent.d_name);
+                        str = ends_with(script_root, REPORT_SUFFIX);
+                        if (str) {
+                                *str = '\0';
+                                desc = script_desc__findnew(script_root);
+                                snprintf(script_path, MAXPATHLEN, "%s/%s",
+                                         lang_path, script_dirent.d_name);
+                                read_script_info(desc, script_path);
+                        }
+                        free(script_root);
+                }
+        }
+
+        fprintf(stdout, "List of available trace scripts:\n");
+        list_for_each_entry(desc, &script_descs, node) {
+                sprintf(first_half, "%s %s", desc->name,
+                        desc->args ? desc->args : "");
+                fprintf(stdout, "  %-36s %s\n", first_half,
+                        desc->half_liner ? desc->half_liner : "");
+        }
+
+        exit(0);
+}
+
 static const char * const annotate_usage[] = {
         "perf trace [<options>] <command>",
         NULL
@@ -284,8 +479,10 @@ static const struct option options[] = {
                     "dump raw trace in ASCII"),
         OPT_BOOLEAN('v', "verbose", &verbose,
                     "be more verbose (show symbol address, etc)"),
-        OPT_BOOLEAN('l', "latency", &latency_format,
+        OPT_BOOLEAN('L', "Latency", &latency_format,
                     "show latency attributes (irqs/preemption disabled, etc)"),
+        OPT_CALLBACK_NOOPT('l', "list", NULL, NULL, "list available scripts",
+                           list_available_scripts),
         OPT_CALLBACK('s', "script", NULL, "name",
                      "script file name (lang:script name, script name, or *)",
                      parse_scriptname),