Jiri Olsa | 592d5a6 | 2015-09-02 09:56:34 +0200 | [diff] [blame] | 1 | #ifndef _GNU_SOURCE |
| 2 | # define _GNU_SOURCE |
| 3 | #endif |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <string.h> |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 8 | #include <errno.h> |
| 9 | #include <unistd.h> |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 10 | #include "fs.h" |
Jiri Olsa | 592d5a6 | 2015-09-02 09:56:34 +0200 | [diff] [blame] | 11 | |
| 12 | #include "tracing_path.h" |
| 13 | |
| 14 | |
| 15 | char tracing_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing"; |
| 16 | char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events"; |
| 17 | |
| 18 | |
| 19 | static void __tracing_path_set(const char *tracing, const char *mountpoint) |
| 20 | { |
| 21 | snprintf(tracing_path, sizeof(tracing_path), "%s/%s", |
| 22 | mountpoint, tracing); |
| 23 | snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s", |
| 24 | mountpoint, tracing, "events"); |
| 25 | } |
| 26 | |
| 27 | static const char *tracing_path_tracefs_mount(void) |
| 28 | { |
| 29 | const char *mnt; |
| 30 | |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 31 | mnt = tracefs__mount(); |
Jiri Olsa | 592d5a6 | 2015-09-02 09:56:34 +0200 | [diff] [blame] | 32 | if (!mnt) |
| 33 | return NULL; |
| 34 | |
| 35 | __tracing_path_set("", mnt); |
| 36 | |
| 37 | return mnt; |
| 38 | } |
| 39 | |
| 40 | static const char *tracing_path_debugfs_mount(void) |
| 41 | { |
| 42 | const char *mnt; |
| 43 | |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 44 | mnt = debugfs__mount(); |
Jiri Olsa | 592d5a6 | 2015-09-02 09:56:34 +0200 | [diff] [blame] | 45 | if (!mnt) |
| 46 | return NULL; |
| 47 | |
| 48 | __tracing_path_set("tracing/", mnt); |
| 49 | |
| 50 | return mnt; |
| 51 | } |
| 52 | |
| 53 | const char *tracing_path_mount(void) |
| 54 | { |
| 55 | const char *mnt; |
| 56 | |
| 57 | mnt = tracing_path_tracefs_mount(); |
| 58 | if (mnt) |
| 59 | return mnt; |
| 60 | |
| 61 | mnt = tracing_path_debugfs_mount(); |
| 62 | |
| 63 | return mnt; |
| 64 | } |
| 65 | |
| 66 | void tracing_path_set(const char *mntpt) |
| 67 | { |
| 68 | __tracing_path_set("tracing/", mntpt); |
| 69 | } |
| 70 | |
| 71 | char *get_tracing_file(const char *name) |
| 72 | { |
| 73 | char *file; |
| 74 | |
| 75 | if (asprintf(&file, "%s/%s", tracing_path, name) < 0) |
| 76 | return NULL; |
| 77 | |
| 78 | return file; |
| 79 | } |
| 80 | |
| 81 | void put_tracing_file(char *file) |
| 82 | { |
| 83 | free(file); |
| 84 | } |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 85 | |
| 86 | static int strerror_open(int err, char *buf, size_t size, const char *filename) |
| 87 | { |
| 88 | char sbuf[128]; |
| 89 | |
| 90 | switch (err) { |
| 91 | case ENOENT: |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 92 | /* |
| 93 | * We will get here if we can't find the tracepoint, but one of |
| 94 | * debugfs or tracefs is configured, which means you probably |
| 95 | * want some tracepoint which wasn't compiled in your kernel. |
| 96 | * - jirka |
| 97 | */ |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 98 | if (debugfs__configured() || tracefs__configured()) { |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 99 | snprintf(buf, size, |
| 100 | "Error:\tFile %s/%s not found.\n" |
| 101 | "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 102 | tracing_events_path, filename); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 103 | break; |
| 104 | } |
| 105 | snprintf(buf, size, "%s", |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 106 | "Error:\tUnable to find debugfs/tracefs\n" |
| 107 | "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n" |
| 108 | "Hint:\tIs the debugfs/tracefs filesystem mounted?\n" |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 109 | "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); |
| 110 | break; |
| 111 | case EACCES: { |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 112 | const char *mountpoint = debugfs__mountpoint(); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 113 | |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 114 | if (!access(mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) { |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 115 | const char *tracefs_mntpoint = tracefs__mountpoint(); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 116 | |
| 117 | if (tracefs_mntpoint) |
Jiri Olsa | 4605eab | 2015-09-02 09:56:43 +0200 | [diff] [blame^] | 118 | mountpoint = tracefs__mountpoint(); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 119 | } |
| 120 | |
| 121 | snprintf(buf, size, |
| 122 | "Error:\tNo permissions to read %s/%s\n" |
| 123 | "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 124 | tracing_events_path, filename, mountpoint); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 125 | } |
| 126 | break; |
| 127 | default: |
| 128 | snprintf(buf, size, "%s", strerror_r(err, sbuf, sizeof(sbuf))); |
| 129 | break; |
| 130 | } |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | int tracing_path__strerror_open_tp(int err, char *buf, size_t size, const char *sys, const char *name) |
| 136 | { |
| 137 | char path[PATH_MAX]; |
| 138 | |
Jiri Olsa | 4f234f0 | 2015-09-02 09:56:36 +0200 | [diff] [blame] | 139 | snprintf(path, PATH_MAX, "%s/%s", sys, name ?: "*"); |
Jiri Olsa | 988bdb3 | 2015-09-02 09:56:35 +0200 | [diff] [blame] | 140 | |
| 141 | return strerror_open(err, buf, size, path); |
| 142 | } |