1592d5a6bSJiri Olsa #ifndef _GNU_SOURCE 2592d5a6bSJiri Olsa # define _GNU_SOURCE 3592d5a6bSJiri Olsa #endif 4592d5a6bSJiri Olsa 5592d5a6bSJiri Olsa #include <stdio.h> 6592d5a6bSJiri Olsa #include <stdlib.h> 7592d5a6bSJiri Olsa #include <string.h> 8988bdb31SJiri Olsa #include <errno.h> 9988bdb31SJiri Olsa #include <unistd.h> 104605eab3SJiri Olsa #include "fs.h" 11592d5a6bSJiri Olsa 12592d5a6bSJiri Olsa #include "tracing_path.h" 13592d5a6bSJiri Olsa 14592d5a6bSJiri Olsa 15ccb5597fSJiri Olsa char tracing_mnt[PATH_MAX] = "/sys/kernel/debug"; 16ccb5597fSJiri Olsa char tracing_path[PATH_MAX] = "/sys/kernel/debug/tracing"; 17ccb5597fSJiri Olsa char tracing_events_path[PATH_MAX] = "/sys/kernel/debug/tracing/events"; 18592d5a6bSJiri Olsa 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 39592d5a6bSJiri Olsa return mnt; 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 52592d5a6bSJiri Olsa return mnt; 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 77592d5a6bSJiri Olsa if (asprintf(&file, "%s/%s", tracing_path, 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 88988bdb31SJiri Olsa static int strerror_open(int err, char *buf, size_t size, const char *filename) 89988bdb31SJiri Olsa { 90988bdb31SJiri Olsa char sbuf[128]; 91988bdb31SJiri Olsa 92988bdb31SJiri Olsa switch (err) { 93988bdb31SJiri Olsa case ENOENT: 944f234f06SJiri Olsa /* 954f234f06SJiri Olsa * We will get here if we can't find the tracepoint, but one of 964f234f06SJiri Olsa * debugfs or tracefs is configured, which means you probably 974f234f06SJiri Olsa * want some tracepoint which wasn't compiled in your kernel. 984f234f06SJiri Olsa * - jirka 994f234f06SJiri Olsa */ 1004605eab3SJiri Olsa if (debugfs__configured() || tracefs__configured()) { 101988bdb31SJiri Olsa snprintf(buf, size, 102988bdb31SJiri Olsa "Error:\tFile %s/%s not found.\n" 103988bdb31SJiri Olsa "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n", 1044f234f06SJiri Olsa tracing_events_path, filename); 105988bdb31SJiri Olsa break; 106988bdb31SJiri Olsa } 107988bdb31SJiri Olsa snprintf(buf, size, "%s", 1084f234f06SJiri Olsa "Error:\tUnable to find debugfs/tracefs\n" 1094f234f06SJiri Olsa "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n" 1104f234f06SJiri Olsa "Hint:\tIs the debugfs/tracefs filesystem mounted?\n" 111988bdb31SJiri Olsa "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'"); 112988bdb31SJiri Olsa break; 113988bdb31SJiri Olsa case EACCES: { 114988bdb31SJiri Olsa snprintf(buf, size, 115988bdb31SJiri Olsa "Error:\tNo permissions to read %s/%s\n" 116988bdb31SJiri Olsa "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n", 117dc240c5dSJiri Olsa tracing_events_path, filename, tracing_mnt); 118988bdb31SJiri Olsa } 119988bdb31SJiri Olsa break; 120988bdb31SJiri Olsa default: 121988bdb31SJiri Olsa snprintf(buf, size, "%s", strerror_r(err, sbuf, sizeof(sbuf))); 122988bdb31SJiri Olsa break; 123988bdb31SJiri Olsa } 124988bdb31SJiri Olsa 125988bdb31SJiri Olsa return 0; 126988bdb31SJiri Olsa } 127988bdb31SJiri Olsa 128988bdb31SJiri Olsa int tracing_path__strerror_open_tp(int err, char *buf, size_t size, const char *sys, const char *name) 129988bdb31SJiri Olsa { 130988bdb31SJiri Olsa char path[PATH_MAX]; 131988bdb31SJiri Olsa 1324f234f06SJiri Olsa snprintf(path, PATH_MAX, "%s/%s", sys, name ?: "*"); 133988bdb31SJiri Olsa 134988bdb31SJiri Olsa return strerror_open(err, buf, size, path); 135988bdb31SJiri Olsa } 136