diff options
| -rw-r--r-- | tools/bpf/bpftool/common.c | 25 | ||||
| -rw-r--r-- | tools/bpf/bpftool/main.h | 2 | ||||
| -rw-r--r-- | tools/bpf/bpftool/tracelog.c | 20 |
3 files changed, 35 insertions, 12 deletions
diff --git a/tools/bpf/bpftool/common.c b/tools/bpf/bpftool/common.c index 24582e8a96fb..1bad6602a282 100644 --- a/tools/bpf/bpftool/common.c +++ b/tools/bpf/bpftool/common.c @@ -76,7 +76,8 @@ void set_max_rlimit(void) setrlimit(RLIMIT_MEMLOCK, &rinf); } -static int mnt_bpffs(const char *target, char *buff, size_t bufflen) +static int +mnt_fs(const char *target, const char *type, char *buff, size_t bufflen) { bool bind_done = false; @@ -98,15 +99,29 @@ static int mnt_bpffs(const char *target, char *buff, size_t bufflen) bind_done = true; } - if (mount("bpf", target, "bpf", 0, "mode=0700")) { - snprintf(buff, bufflen, "mount -t bpf bpf %s failed: %s", - target, strerror(errno)); + if (mount(type, target, type, 0, "mode=0700")) { + snprintf(buff, bufflen, "mount -t %s %s %s failed: %s", + type, type, target, strerror(errno)); return -1; } return 0; } +int mount_tracefs(const char *target) +{ + char err_str[ERR_MAX_LEN]; + int err; + + err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN); + if (err) { + err_str[ERR_MAX_LEN - 1] = '\0'; + p_err("can't mount tracefs: %s", err_str); + } + + return err; +} + int open_obj_pinned(char *path, bool quiet) { int fd; @@ -162,7 +177,7 @@ int mount_bpffs_for_pin(const char *name) /* nothing to do if already mounted */ goto out_free; - err = mnt_bpffs(dir, err_str, ERR_MAX_LEN); + err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN); if (err) { err_str[ERR_MAX_LEN - 1] = '\0'; p_err("can't mount BPF file system to pin the object (%s): %s", diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h index 9487345b04a7..9e4499c926fa 100644 --- a/tools/bpf/bpftool/main.h +++ b/tools/bpf/bpftool/main.h @@ -98,6 +98,8 @@ void usage(void) __noreturn; void set_max_rlimit(void); +int mount_tracefs(const char *target); + struct pinned_obj_table { DECLARE_HASHTABLE(table, 16); }; diff --git a/tools/bpf/bpftool/tracelog.c b/tools/bpf/bpftool/tracelog.c index 1fa8e513f590..2dc36dfa0896 100644 --- a/tools/bpf/bpftool/tracelog.c +++ b/tools/bpf/bpftool/tracelog.c @@ -54,7 +54,7 @@ find_tracefs_mnt_single(unsigned long magic, char *mnt, const char *mntpt) return true; } -static bool find_tracefs_pipe(char *mnt) +static bool get_tracefs_pipe(char *mnt) { static const char * const known_mnts[] = { "/sys/kernel/debug/tracing", @@ -88,7 +88,17 @@ static bool find_tracefs_pipe(char *mnt) fclose(fp); /* The string from fscanf() might be truncated, check mnt is valid */ - if (!found || validate_tracefs_mnt(mnt, TRACEFS_MAGIC)) + if (found && validate_tracefs_mnt(mnt, TRACEFS_MAGIC)) + goto exit_found; + + p_info("could not find tracefs, attempting to mount it now"); + /* Most of the time, tracefs is automatically mounted by debugfs at + * /sys/kernel/debug/tracing when we try to access it. If we could not + * find it, it is likely that debugfs is not mounted. Let's give one + * attempt at mounting just tracefs at /sys/kernel/tracing. + */ + strcpy(mnt, known_mnts[1]); + if (mount_tracefs(mnt)) return false; exit_found: @@ -115,17 +125,13 @@ int do_tracelog(int argc, char **argv) .sa_handler = exit_tracelog }; char trace_pipe[PATH_MAX]; - bool found_trace_pipe; size_t buff_len = 0; if (json_output) jsonw_start_array(json_wtr); - found_trace_pipe = find_tracefs_pipe(trace_pipe); - if (!found_trace_pipe) { - p_err("could not find trace pipe, tracefs not mounted?"); + if (!get_tracefs_pipe(trace_pipe)) return -1; - } trace_pipe_fd = fopen(trace_pipe, "r"); if (!trace_pipe_fd) { |