1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 2592d5a6bSJiri Olsa #ifndef _GNU_SOURCE 3592d5a6bSJiri Olsa # define _GNU_SOURCE 4592d5a6bSJiri Olsa #endif 5592d5a6bSJiri Olsa 6592d5a6bSJiri Olsa #include <stdio.h> 7592d5a6bSJiri Olsa #include <stdlib.h> 8592d5a6bSJiri Olsa #include <string.h> 9b31e3e33SArnaldo Carvalho de Melo #include <linux/string.h> 10988bdb31SJiri Olsa #include <errno.h> 11988bdb31SJiri Olsa #include <unistd.h> 124605eab3SJiri Olsa #include "fs.h" 13592d5a6bSJiri Olsa 14592d5a6bSJiri Olsa #include "tracing_path.h" 15592d5a6bSJiri Olsa 1600a62703SArnaldo Carvalho de Melo static char tracing_mnt[PATH_MAX] = "/sys/kernel/debug"; 1717c257e8SArnaldo Carvalho de Melo static char tracing_path[PATH_MAX] = "/sys/kernel/debug/tracing"; 18789e4650SArnaldo Carvalho de Melo static char tracing_events_path[PATH_MAX] = "/sys/kernel/debug/tracing/events"; 19592d5a6bSJiri Olsa 20592d5a6bSJiri Olsa static void __tracing_path_set(const char *tracing, const char *mountpoint) 21592d5a6bSJiri Olsa { 22dc240c5dSJiri Olsa snprintf(tracing_mnt, sizeof(tracing_mnt), "%s", mountpoint); 23592d5a6bSJiri Olsa snprintf(tracing_path, sizeof(tracing_path), "%s/%s", 24592d5a6bSJiri Olsa mountpoint, tracing); 25592d5a6bSJiri Olsa snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s", 26592d5a6bSJiri Olsa mountpoint, tracing, "events"); 27592d5a6bSJiri Olsa } 28592d5a6bSJiri Olsa 29592d5a6bSJiri Olsa static const char *tracing_path_tracefs_mount(void) 30592d5a6bSJiri Olsa { 31592d5a6bSJiri Olsa const char *mnt; 32592d5a6bSJiri Olsa 334605eab3SJiri Olsa mnt = tracefs__mount(); 34592d5a6bSJiri Olsa if (!mnt) 35592d5a6bSJiri Olsa return NULL; 36592d5a6bSJiri Olsa 37592d5a6bSJiri Olsa __tracing_path_set("", mnt); 38592d5a6bSJiri Olsa 39c458a620SJiri Olsa return tracing_path; 40592d5a6bSJiri Olsa } 41592d5a6bSJiri Olsa 42592d5a6bSJiri Olsa static const char *tracing_path_debugfs_mount(void) 43592d5a6bSJiri Olsa { 44592d5a6bSJiri Olsa const char *mnt; 45592d5a6bSJiri Olsa 464605eab3SJiri Olsa mnt = debugfs__mount(); 47592d5a6bSJiri Olsa if (!mnt) 48592d5a6bSJiri Olsa return NULL; 49592d5a6bSJiri Olsa 50592d5a6bSJiri Olsa __tracing_path_set("tracing/", mnt); 51592d5a6bSJiri Olsa 52c458a620SJiri Olsa return tracing_path; 53592d5a6bSJiri Olsa } 54592d5a6bSJiri Olsa 55592d5a6bSJiri Olsa const char *tracing_path_mount(void) 56592d5a6bSJiri Olsa { 57592d5a6bSJiri Olsa const char *mnt; 58592d5a6bSJiri Olsa 59592d5a6bSJiri Olsa mnt = tracing_path_tracefs_mount(); 60592d5a6bSJiri Olsa if (mnt) 61592d5a6bSJiri Olsa return mnt; 62592d5a6bSJiri Olsa 63592d5a6bSJiri Olsa mnt = tracing_path_debugfs_mount(); 64592d5a6bSJiri Olsa 65592d5a6bSJiri Olsa return mnt; 66592d5a6bSJiri Olsa } 67592d5a6bSJiri Olsa 68592d5a6bSJiri Olsa void tracing_path_set(const char *mntpt) 69592d5a6bSJiri Olsa { 70592d5a6bSJiri Olsa __tracing_path_set("tracing/", mntpt); 71592d5a6bSJiri Olsa } 72592d5a6bSJiri Olsa 73592d5a6bSJiri Olsa char *get_tracing_file(const char *name) 74592d5a6bSJiri Olsa { 75592d5a6bSJiri Olsa char *file; 76592d5a6bSJiri Olsa 7717c257e8SArnaldo Carvalho de Melo if (asprintf(&file, "%s/%s", tracing_path_mount(), name) < 0) 78592d5a6bSJiri Olsa return NULL; 79592d5a6bSJiri Olsa 80592d5a6bSJiri Olsa return file; 81592d5a6bSJiri Olsa } 82592d5a6bSJiri Olsa 83592d5a6bSJiri Olsa void put_tracing_file(char *file) 84592d5a6bSJiri Olsa { 85592d5a6bSJiri Olsa free(file); 86592d5a6bSJiri Olsa } 87988bdb31SJiri Olsa 8840c3c0c9SArnaldo Carvalho de Melo char *get_events_file(const char *name) 8940c3c0c9SArnaldo Carvalho de Melo { 9040c3c0c9SArnaldo Carvalho de Melo char *file; 9140c3c0c9SArnaldo Carvalho de Melo 9240c3c0c9SArnaldo Carvalho de Melo if (asprintf(&file, "%s/events/%s", tracing_path_mount(), name) < 0) 9340c3c0c9SArnaldo Carvalho de Melo return NULL; 9440c3c0c9SArnaldo Carvalho de Melo 9540c3c0c9SArnaldo Carvalho de Melo return file; 9640c3c0c9SArnaldo Carvalho de Melo } 9740c3c0c9SArnaldo Carvalho de Melo 9840c3c0c9SArnaldo Carvalho de Melo void put_events_file(char *file) 9940c3c0c9SArnaldo Carvalho de Melo { 10040c3c0c9SArnaldo Carvalho de Melo free(file); 10140c3c0c9SArnaldo Carvalho de Melo } 10240c3c0c9SArnaldo Carvalho de Melo 1037014e0e3SArnaldo Carvalho de Melo DIR *tracing_events__opendir(void) 1047014e0e3SArnaldo Carvalho de Melo { 1057014e0e3SArnaldo Carvalho de Melo DIR *dir = NULL; 1067014e0e3SArnaldo Carvalho de Melo char *path = get_tracing_file("events"); 1077014e0e3SArnaldo Carvalho de Melo 1087014e0e3SArnaldo Carvalho de Melo if (path) { 1097014e0e3SArnaldo Carvalho de Melo dir = opendir(path); 1107014e0e3SArnaldo Carvalho de Melo put_events_file(path); 1117014e0e3SArnaldo Carvalho de Melo } 1127014e0e3SArnaldo Carvalho de Melo 1137014e0e3SArnaldo Carvalho de Melo return dir; 1147014e0e3SArnaldo Carvalho de Melo } 1157014e0e3SArnaldo Carvalho de Melo 116*1504b6f9SIan Rogers int tracing_events__scandir_alphasort(struct dirent ***namelist) 117*1504b6f9SIan Rogers { 118*1504b6f9SIan Rogers char *path = get_tracing_file("events"); 119*1504b6f9SIan Rogers int ret; 120*1504b6f9SIan Rogers 121*1504b6f9SIan Rogers if (!path) { 122*1504b6f9SIan Rogers *namelist = NULL; 123*1504b6f9SIan Rogers return 0; 124*1504b6f9SIan Rogers } 125*1504b6f9SIan Rogers 126*1504b6f9SIan Rogers ret = scandir(path, namelist, NULL, alphasort); 127*1504b6f9SIan Rogers put_events_file(path); 128*1504b6f9SIan Rogers 129*1504b6f9SIan Rogers return ret; 130*1504b6f9SIan Rogers } 131*1504b6f9SIan Rogers 13227cf5706SRavi Bangoria int tracing_path__strerror_open_tp(int err, char *buf, size_t size, 13327cf5706SRavi Bangoria const char *sys, const char *name) 134988bdb31SJiri Olsa { 135988bdb31SJiri Olsa char sbuf[128]; 13627cf5706SRavi Bangoria char filename[PATH_MAX]; 13727cf5706SRavi Bangoria 13827cf5706SRavi Bangoria snprintf(filename, PATH_MAX, "%s/%s", sys, name ?: "*"); 139988bdb31SJiri Olsa 140988bdb31SJiri Olsa switch (err) { 141988bdb31SJiri Olsa case ENOENT: 1424f234f06SJiri Olsa /* 1434f234f06SJiri Olsa * We will get here if we can't find the tracepoint, but one of 1444f234f06SJiri Olsa * debugfs or tracefs is configured, which means you probably 1454f234f06SJiri Olsa * want some tracepoint which wasn't compiled in your kernel. 1464f234f06SJiri Olsa * - jirka 1474f234f06SJiri Olsa */ 1484605eab3SJiri Olsa if (debugfs__configured() || tracefs__configured()) { 14927cf5706SRavi Bangoria /* sdt markers */ 15027cf5706SRavi Bangoria if (!strncmp(filename, "sdt_", 4)) { 15127cf5706SRavi Bangoria snprintf(buf, size, 15227cf5706SRavi Bangoria "Error:\tFile %s/%s not found.\n" 15327cf5706SRavi Bangoria "Hint:\tSDT event cannot be directly recorded on.\n" 15427cf5706SRavi Bangoria "\tPlease first use 'perf probe %s:%s' before recording it.\n", 15527cf5706SRavi Bangoria tracing_events_path, filename, sys, name); 15627cf5706SRavi Bangoria } else { 157988bdb31SJiri Olsa snprintf(buf, size, 158988bdb31SJiri Olsa "Error:\tFile %s/%s not found.\n" 159988bdb31SJiri Olsa "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", 1604f234f06SJiri Olsa tracing_events_path, filename); 16127cf5706SRavi Bangoria } 162988bdb31SJiri Olsa break; 163988bdb31SJiri Olsa } 164988bdb31SJiri Olsa snprintf(buf, size, "%s", 1654f234f06SJiri Olsa "Error:\tUnable to find debugfs/tracefs\n" 1664f234f06SJiri Olsa "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n" 1674f234f06SJiri Olsa "Hint:\tIs the debugfs/tracefs filesystem mounted?\n" 168988bdb31SJiri Olsa "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); 169988bdb31SJiri Olsa break; 170988bdb31SJiri Olsa case EACCES: { 171988bdb31SJiri Olsa snprintf(buf, size, 172988bdb31SJiri Olsa "Error:\tNo permissions to read %s/%s\n" 173988bdb31SJiri Olsa "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", 17400a62703SArnaldo Carvalho de Melo tracing_events_path, filename, tracing_path_mount()); 175988bdb31SJiri Olsa } 176988bdb31SJiri Olsa break; 177988bdb31SJiri Olsa default: 178b31e3e33SArnaldo Carvalho de Melo snprintf(buf, size, "%s", str_error_r(err, sbuf, sizeof(sbuf))); 179988bdb31SJiri Olsa break; 180988bdb31SJiri Olsa } 181988bdb31SJiri Olsa 182988bdb31SJiri Olsa return 0; 183988bdb31SJiri Olsa } 184