diff options
Diffstat (limited to 'tools/perf/util/probe-file.c')
| -rw-r--r-- | tools/perf/util/probe-file.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c new file mode 100644 index 000000000000..bbb243717ec8 --- /dev/null +++ b/tools/perf/util/probe-file.c @@ -0,0 +1,301 @@ +/* + * probe-file.c : operate ftrace k/uprobe events files + * + * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include "util.h" +#include "event.h" +#include "strlist.h" +#include "debug.h" +#include "cache.h" +#include "color.h" +#include "symbol.h" +#include "thread.h" +#include <api/fs/debugfs.h> +#include <api/fs/tracefs.h> +#include "probe-event.h" +#include "probe-file.h" +#include "session.h" + +#define MAX_CMDLEN 256 + +static void print_open_warning(int err, bool uprobe) +{ + char sbuf[STRERR_BUFSIZE]; + + if (err == -ENOENT) { + const char *config; + + if (uprobe) + config = "CONFIG_UPROBE_EVENTS"; + else + config = "CONFIG_KPROBE_EVENTS"; + + pr_warning("%cprobe_events file does not exist" + " - please rebuild kernel with %s.\n", + uprobe ? 'u' : 'k', config); + } else if (err == -ENOTSUP) + pr_warning("Tracefs or debugfs is not mounted.\n"); + else + pr_warning("Failed to open %cprobe_events: %s\n", + uprobe ? 'u' : 'k', + strerror_r(-err, sbuf, sizeof(sbuf))); +} + +static void print_both_open_warning(int kerr, int uerr) +{ + /* Both kprobes and uprobes are disabled, warn it. */ + if (kerr == -ENOTSUP && uerr == -ENOTSUP) + pr_warning("Tracefs or debugfs is not mounted.\n"); + else if (kerr == -ENOENT && uerr == -ENOENT) + pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS " + "or/and CONFIG_UPROBE_EVENTS.\n"); + else { + char sbuf[STRERR_BUFSIZE]; + pr_warning("Failed to open kprobe events: %s.\n", + strerror_r(-kerr, sbuf, sizeof(sbuf))); + pr_warning("Failed to open uprobe events: %s.\n", + strerror_r(-uerr, sbuf, sizeof(sbuf))); + } +} + +static int open_probe_events(const char *trace_file, bool readwrite) +{ + char buf[PATH_MAX]; + const char *__debugfs; + const char *tracing_dir = ""; + int ret; + + __debugfs = tracefs_find_mountpoint(); + if (__debugfs == NULL) { + tracing_dir = "tracing/"; + + __debugfs = debugfs_find_mountpoint(); + if (__debugfs == NULL) + return -ENOTSUP; + } + + ret = e_snprintf(buf, PATH_MAX, "%s/%s%s", + __debugfs, tracing_dir, trace_file); + if (ret >= 0) { + pr_debug("Opening %s write=%d\n", buf, readwrite); + if (readwrite && !probe_event_dry_run) + ret = open(buf, O_RDWR | O_APPEND, 0); + else + ret = open(buf, O_RDONLY, 0); + + if (ret < 0) + ret = -errno; + } + return ret; +} + +static int open_kprobe_events(bool readwrite) +{ + return open_probe_events("kprobe_events", readwrite); +} + +static int open_uprobe_events(bool readwrite) +{ + return open_probe_events("uprobe_events", readwrite); +} + +int probe_file__open(int flag) +{ + int fd; + + if (flag & PF_FL_UPROBE) + fd = open_uprobe_events(flag & PF_FL_RW); + else + fd = open_kprobe_events(flag & PF_FL_RW); + if (fd < 0) + print_open_warning(fd, flag & PF_FL_UPROBE); + + return fd; +} + +int probe_file__open_both(int *kfd, int *ufd, int flag) +{ + if (!kfd || !ufd) + return -EINVAL; + + *kfd = open_kprobe_events(flag & PF_FL_RW); + *ufd = open_uprobe_events(flag & PF_FL_RW); + if (*kfd < 0 && *ufd < 0) { + print_both_open_warning(*kfd, *ufd); + return *kfd; + } + + return 0; +} + +/* Get raw string list of current kprobe_events or uprobe_events */ +struct strlist *probe_file__get_rawlist(int fd) +{ + int ret, idx; + FILE *fp; + char buf[MAX_CMDLEN]; + char *p; + struct strlist *sl; + + sl = strlist__new(NULL, NULL); + + fp = fdopen(dup(fd), "r"); + while (!feof(fp)) { + p = fgets(buf, MAX_CMDLEN, fp); + if (!p) + break; + + idx = strlen(p) - 1; + if (p[idx] == '\n') + p[idx] = '\0'; + ret = strlist__add(sl, buf); + if (ret < 0) { + pr_debug("strlist__add failed (%d)\n", ret); + strlist__delete(sl); + return NULL; + } + } + fclose(fp); + + return sl; +} + +static struct strlist *__probe_file__get_namelist(int fd, bool include_group) +{ + char buf[128]; + struct strlist *sl, *rawlist; + struct str_node *ent; + struct probe_trace_event tev; + int ret = 0; + + memset(&tev, 0, sizeof(tev)); + rawlist = probe_file__get_rawlist(fd); + if (!rawlist) + return NULL; + sl = strlist__new(NULL, NULL); + strlist__for_each(ent, rawlist) { + ret = parse_probe_trace_command(ent->s, &tev); + if (ret < 0) + break; + if (include_group) { + ret = e_snprintf(buf, 128, "%s:%s", tev.group, + tev.event); + if (ret >= 0) + ret = strlist__add(sl, buf); + } else + ret = strlist__add(sl, tev.event); + clear_probe_trace_event(&tev); + if (ret < 0) + break; + } + strlist__delete(rawlist); + + if (ret < 0) { + strlist__delete(sl); + return NULL; + } + return sl; +} + +/* Get current perf-probe event names */ +struct strlist *probe_file__get_namelist(int fd) +{ + return __probe_file__get_namelist(fd, false); +} + +int probe_file__add_event(int fd, struct probe_trace_event *tev) +{ + int ret = 0; + char *buf = synthesize_probe_trace_command(tev); + char sbuf[STRERR_BUFSIZE]; + + if (!buf) { + pr_debug("Failed to synthesize probe trace event.\n"); + return -EINVAL; + } + + pr_debug("Writing event: %s\n", buf); + if (!probe_event_dry_run) { + ret = write(fd, buf, strlen(buf)); + if (ret <= 0) { + ret = -errno; + pr_warning("Failed to write event: %s\n", + strerror_r(errno, sbuf, sizeof(sbuf))); + } + } + free(buf); + + return ret; +} + +static int __del_trace_probe_event(int fd, struct str_node *ent) +{ + char *p; + char buf[128]; + int ret; + + /* Convert from perf-probe event to trace-probe event */ + ret = e_snprintf(buf, 128, "-:%s", ent->s); + if (ret < 0) + goto error; + + p = strchr(buf + 2, ':'); + if (!p) { + pr_debug("Internal error: %s should have ':' but not.\n", + ent->s); + ret = -ENOTSUP; + goto error; + } + *p = '/'; + + pr_debug("Writing event: %s\n", buf); + ret = write(fd, buf, strlen(buf)); + if (ret < 0) { + ret = -errno; + goto error; + } + + pr_info("Removed event: %s\n", ent->s); + return 0; +error: + pr_warning("Failed to delete event: %s\n", + strerror_r(-ret, buf, sizeof(buf))); + return ret; +} + +int probe_file__del_events(int fd, struct strfilter *filter) +{ + struct strlist *namelist; + struct str_node *ent; + const char *p; + int ret = -ENOENT; + + namelist = __probe_file__get_namelist(fd, true); + if (!namelist) + return -ENOENT; + + strlist__for_each(ent, namelist) { + p = strchr(ent->s, ':'); + if ((p && strfilter__compare(filter, p + 1)) || + strfilter__compare(filter, ent->s)) { + ret = __del_trace_probe_event(fd, ent); + if (ret < 0) + break; + } + } + strlist__delete(namelist); + + return ret; +} |