1 files changed, 39 insertions, 51 deletions

diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index af4b0573b37f..5ea8973ad331 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -20,6 +20,7 @@
  */
 #define _GNU_SOURCE
 #include <dirent.h>
+#include <mntent.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -33,10 +34,11 @@
 #include <ctype.h>
 #include <errno.h>
 #include <stdbool.h>
+#include <linux/kernel.h>
 
 #include "../perf.h"
 #include "trace-event.h"
-
+#include "debugfs.h"
 
 #define VERSION "0.5"
 
@@ -101,32 +103,12 @@ void *malloc_or_die(unsigned int size)
 
 static const char *find_debugfs(void)
 {
-        static char debugfs[MAX_PATH+1];
-        static int debugfs_found;
-        char type[100];
-        FILE *fp;
-
-        if (debugfs_found)
-                return debugfs;
-
-        if ((fp = fopen("/proc/mounts","r")) == NULL)
-                die("Can't open /proc/mounts for read");
-
-        while (fscanf(fp, "%*s %"
-                      STR(MAX_PATH)
-                      "s %99s %*s %*d %*d\n",
-                      debugfs, type) == 2) {
-                if (strcmp(type, "debugfs") == 0)
-                        break;
-        }
-        fclose(fp);
-
-        if (strcmp(type, "debugfs") != 0)
-                die("debugfs not mounted, please mount");
+        const char *path = debugfs_mount(NULL);
 
-        debugfs_found = 1;
+        if (!path)
+                die("Your kernel not support debugfs filesystem");
 
-        return debugfs;
+        return path;
 }
 
 /*
@@ -271,6 +253,8 @@ static void read_header_files(void)
         write_or_die("header_page", 12);
         write_or_die(&size, 8);
         check_size = copy_file_fd(fd);
+        close(fd);
+
         if (size != check_size)
                 die("wrong size for '%s' size=%lld read=%lld",
                     path, size, check_size);
@@ -289,6 +273,7 @@ static void read_header_files(void)
         if (size != check_size)
                 die("wrong size for '%s'", path);
         put_tracing_file(path);
+        close(fd);
 }
 
 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
@@ -317,7 +302,8 @@ static void copy_event_system(const char *sys, struct tracepoint_path *tps)
                 die("can't read directory '%s'", sys);
 
         while ((dent = readdir(dir))) {
-                if (strcmp(dent->d_name, ".") == 0 ||
+                if (dent->d_type != DT_DIR ||
+                    strcmp(dent->d_name, ".") == 0 ||
                     strcmp(dent->d_name, "..") == 0 ||
                     !name_in_tp_list(dent->d_name, tps))
                         continue;
@@ -334,7 +320,8 @@ static void copy_event_system(const char *sys, struct tracepoint_path *tps)
 
         rewinddir(dir);
         while ((dent = readdir(dir))) {
-                if (strcmp(dent->d_name, ".") == 0 ||
+                if (dent->d_type != DT_DIR ||
+                    strcmp(dent->d_name, ".") == 0 ||
                     strcmp(dent->d_name, "..") == 0 ||
                     !name_in_tp_list(dent->d_name, tps))
                         continue;
@@ -353,6 +340,7 @@ static void copy_event_system(const char *sys, struct tracepoint_path *tps)
 
                 free(format);
         }
+        closedir(dir);
 }
 
 static void read_ftrace_files(struct tracepoint_path *tps)
@@ -394,26 +382,21 @@ static void read_event_files(struct tracepoint_path *tps)
                 die("can't read directory '%s'", path);
 
         while ((dent = readdir(dir))) {
-                if (strcmp(dent->d_name, ".") == 0 ||
+                if (dent->d_type != DT_DIR ||
+                    strcmp(dent->d_name, ".") == 0 ||
                     strcmp(dent->d_name, "..") == 0 ||
                     strcmp(dent->d_name, "ftrace") == 0 ||
                     !system_in_tp_list(dent->d_name, tps))
                         continue;
-                sys = malloc_or_die(strlen(path) + strlen(dent->d_name) + 2);
-                sprintf(sys, "%s/%s", path, dent->d_name);
-                ret = stat(sys, &st);
-                free(sys);
-                if (ret < 0)
-                        continue;
-                if (S_ISDIR(st.st_mode))
-                        count++;
+                count++;
         }
 
         write_or_die(&count, 4);
 
         rewinddir(dir);
         while ((dent = readdir(dir))) {
-                if (strcmp(dent->d_name, ".") == 0 ||
+                if (dent->d_type != DT_DIR ||
+                    strcmp(dent->d_name, ".") == 0 ||
                     strcmp(dent->d_name, "..") == 0 ||
                     strcmp(dent->d_name, "ftrace") == 0 ||
                     !system_in_tp_list(dent->d_name, tps))
@@ -422,14 +405,13 @@ static void read_event_files(struct tracepoint_path *tps)
                 sprintf(sys, "%s/%s", path, dent->d_name);
                 ret = stat(sys, &st);
                 if (ret >= 0) {
-                        if (S_ISDIR(st.st_mode)) {
-                                write_or_die(dent->d_name, strlen(dent->d_name) + 1);
-                                copy_event_system(sys, tps);
-                        }
+                        write_or_die(dent->d_name, strlen(dent->d_name) + 1);
+                        copy_event_system(sys, tps);
                 }
                 free(sys);
         }
 
+        closedir(dir);
         put_tracing_file(path);
 }
 
@@ -483,27 +465,33 @@ static struct tracepoint_path *
 get_tracepoints_path(struct perf_event_attr *pattrs, int nb_events)
 {
         struct tracepoint_path path, *ppath = &path;
-        int i;
+        int i, nr_tracepoints = 0;
 
         for (i = 0; i < nb_events; i++) {
                 if (pattrs[i].type != PERF_TYPE_TRACEPOINT)
                         continue;
+                ++nr_tracepoints;
                 ppath->next = tracepoint_id_to_path(pattrs[i].config);
                 if (!ppath->next)
                         die("%s\n", "No memory to alloc tracepoints list");
                 ppath = ppath->next;
         }
 
-        return path.next;
+        return nr_tracepoints > 0 ? path.next : NULL;
 }
-void read_tracing_data(struct perf_event_attr *pattrs, int nb_events)
+
+int read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events)
 {
         char buf[BUFSIZ];
-        struct tracepoint_path *tps;
+        struct tracepoint_path *tps = get_tracepoints_path(pattrs, nb_events);
+
+        /*
+         * What? No tracepoints? No sense writing anything here, bail out.
+         */
+        if (tps == NULL)
+                return -1;
 
-        output_fd = open(output_file, O_WRONLY | O_CREAT | O_TRUNC | O_LARGEFILE, 0644);
-        if (output_fd < 0)
-                die("creating file '%s'", output_file);
+        output_fd = fd;
 
         buf[0] = 23;
         buf[1] = 8;
@@ -527,14 +515,14 @@ void read_tracing_data(struct perf_event_attr *pattrs, int nb_events)
         write_or_die(buf, 1);
 
         /* save page_size */
-        page_size = getpagesize();
+        page_size = sysconf(_SC_PAGESIZE);
         write_or_die(&page_size, 4);
 
-        tps = get_tracepoints_path(pattrs, nb_events);
-
         read_header_files();
         read_ftrace_files(tps);
         read_event_files(tps);
         read_proc_kallsyms();
         read_ftrace_printk();
+
+        return 0;
 }