diff options
Diffstat (limited to 'tools/perf/builtin-probe.c')
| -rw-r--r-- | tools/perf/builtin-probe.c | 738 |
1 files changed, 738 insertions, 0 deletions
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c new file mode 100644 index 000000000..6b1507566 --- /dev/null +++ b/tools/perf/builtin-probe.c @@ -0,0 +1,738 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * builtin-probe.c + * + * Builtin probe command: Set up probe events by C expression + * + * Written by Masami Hiramatsu <mhiramat@redhat.com> + */ +#include <sys/utsname.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> + +#include "builtin.h" +#include "namespaces.h" +#include "util/build-id.h" +#include "util/strlist.h" +#include "util/strfilter.h" +#include "util/symbol_conf.h" +#include "util/debug.h" +#include <subcmd/parse-options.h> +#include "util/probe-finder.h" +#include "util/probe-event.h" +#include "util/probe-file.h" +#include <linux/string.h> +#include <linux/zalloc.h> + +#define DEFAULT_VAR_FILTER "!__k???tab_* & !__crc_*" +#define DEFAULT_FUNC_FILTER "!_*" +#define DEFAULT_LIST_FILTER "*" + +/* Session management structure */ +static struct { + int command; /* Command short_name */ + bool list_events; + bool uprobes; + bool quiet; + bool target_used; + int nevents; + struct perf_probe_event events[MAX_PROBES]; + struct line_range line_range; + char *target; + struct strfilter *filter; + struct nsinfo *nsi; +} params; + +/* Parse an event definition. Note that any error must die. */ +static int parse_probe_event(const char *str) +{ + struct perf_probe_event *pev = ¶ms.events[params.nevents]; + int ret; + + pr_debug("probe-definition(%d): %s\n", params.nevents, str); + if (++params.nevents == MAX_PROBES) { + pr_err("Too many probes (> %d) were specified.", MAX_PROBES); + return -1; + } + + pev->uprobes = params.uprobes; + if (params.target) { + pev->target = strdup(params.target); + if (!pev->target) + return -ENOMEM; + params.target_used = true; + } + + pev->nsi = nsinfo__get(params.nsi); + + /* Parse a perf-probe command into event */ + ret = parse_perf_probe_command(str, pev); + pr_debug("%d arguments\n", pev->nargs); + + return ret; +} + +static int params_add_filter(const char *str) +{ + const char *err = NULL; + int ret = 0; + + pr_debug2("Add filter: %s\n", str); + if (!params.filter) { + params.filter = strfilter__new(str, &err); + if (!params.filter) + ret = err ? -EINVAL : -ENOMEM; + } else + ret = strfilter__or(params.filter, str, &err); + + if (ret == -EINVAL) { + pr_err("Filter parse error at %td.\n", err - str + 1); + pr_err("Source: \"%s\"\n", str); + pr_err(" %*c\n", (int)(err - str + 1), '^'); + } + + return ret; +} + +static int set_target(const char *ptr) +{ + int found = 0; + const char *buf; + + /* + * The first argument after options can be an absolute path + * to an executable / library or kernel module. + * + * TODO: Support relative path, and $PATH, $LD_LIBRARY_PATH, + * short module name. + */ + if (!params.target && ptr && *ptr == '/') { + params.target = strdup(ptr); + if (!params.target) + return -ENOMEM; + params.target_used = false; + + found = 1; + buf = ptr + (strlen(ptr) - 3); + + if (strcmp(buf, ".ko")) + params.uprobes = true; + + } + + return found; +} + +static int parse_probe_event_argv(int argc, const char **argv) +{ + int i, len, ret, found_target; + char *buf; + + found_target = set_target(argv[0]); + if (found_target < 0) + return found_target; + + if (found_target && argc == 1) + return 0; + + /* Bind up rest arguments */ + len = 0; + for (i = 0; i < argc; i++) { + if (i == 0 && found_target) + continue; + + len += strlen(argv[i]) + 1; + } + buf = zalloc(len + 1); + if (buf == NULL) + return -ENOMEM; + len = 0; + for (i = 0; i < argc; i++) { + if (i == 0 && found_target) + continue; + + len += sprintf(&buf[len], "%s ", argv[i]); + } + ret = parse_probe_event(buf); + free(buf); + return ret; +} + +static int opt_set_target(const struct option *opt, const char *str, + int unset __maybe_unused) +{ + int ret = -ENOENT; + char *tmp; + + if (str) { + if (!strcmp(opt->long_name, "exec")) + params.uprobes = true; + else if (!strcmp(opt->long_name, "module")) + params.uprobes = false; + else + return ret; + + /* Expand given path to absolute path, except for modulename */ + if (params.uprobes || strchr(str, '/')) { + tmp = nsinfo__realpath(str, params.nsi); + if (!tmp) { + pr_warning("Failed to get the absolute path of %s: %m\n", str); + return ret; + } + } else { + tmp = strdup(str); + if (!tmp) + return -ENOMEM; + } + free(params.target); + params.target = tmp; + params.target_used = false; + ret = 0; + } + + return ret; +} + +static int opt_set_target_ns(const struct option *opt __maybe_unused, + const char *str, int unset __maybe_unused) +{ + int ret = -ENOENT; + pid_t ns_pid; + struct nsinfo *nsip; + + if (str) { + errno = 0; + ns_pid = (pid_t)strtol(str, NULL, 10); + if (errno != 0) { + ret = -errno; + pr_warning("Failed to parse %s as a pid: %s\n", str, + strerror(errno)); + return ret; + } + nsip = nsinfo__new(ns_pid); + if (nsip && nsip->need_setns) + params.nsi = nsinfo__get(nsip); + nsinfo__put(nsip); + + ret = 0; + } + + return ret; +} + + +/* Command option callbacks */ + +#ifdef HAVE_DWARF_SUPPORT +static int opt_show_lines(const struct option *opt, + const char *str, int unset __maybe_unused) +{ + int ret = 0; + + if (!str) + return 0; + + if (params.command == 'L') { + pr_warning("Warning: more than one --line options are" + " detected. Only the first one is valid.\n"); + return 0; + } + + params.command = opt->short_name; + ret = parse_line_range_desc(str, ¶ms.line_range); + + return ret; +} + +static int opt_show_vars(const struct option *opt, + const char *str, int unset __maybe_unused) +{ + struct perf_probe_event *pev = ¶ms.events[params.nevents]; + int ret; + + if (!str) + return 0; + + ret = parse_probe_event(str); + if (!ret && pev->nargs != 0) { + pr_err(" Error: '--vars' doesn't accept arguments.\n"); + return -EINVAL; + } + params.command = opt->short_name; + + return ret; +} +#else +# define opt_show_lines NULL +# define opt_show_vars NULL +#endif +static int opt_add_probe_event(const struct option *opt, + const char *str, int unset __maybe_unused) +{ + if (str) { + params.command = opt->short_name; + return parse_probe_event(str); + } + + return 0; +} + +static int opt_set_filter_with_command(const struct option *opt, + const char *str, int unset) +{ + if (!unset) + params.command = opt->short_name; + + if (str) + return params_add_filter(str); + + return 0; +} + +static int opt_set_filter(const struct option *opt __maybe_unused, + const char *str, int unset __maybe_unused) +{ + if (str) + return params_add_filter(str); + + return 0; +} + +static int init_params(void) +{ + return line_range__init(¶ms.line_range); +} + +static void cleanup_params(void) +{ + int i; + + for (i = 0; i < params.nevents; i++) + clear_perf_probe_event(params.events + i); + line_range__clear(¶ms.line_range); + free(params.target); + strfilter__delete(params.filter); + nsinfo__put(params.nsi); + memset(¶ms, 0, sizeof(params)); +} + +static void pr_err_with_code(const char *msg, int err) +{ + char sbuf[STRERR_BUFSIZE]; + + pr_err("%s", msg); + pr_debug(" Reason: %s (Code: %d)", + str_error_r(-err, sbuf, sizeof(sbuf)), err); + pr_err("\n"); +} + +static int perf_add_probe_events(struct perf_probe_event *pevs, int npevs) +{ + int ret; + int i, k; + const char *event = NULL, *group = NULL; + + ret = init_probe_symbol_maps(pevs->uprobes); + if (ret < 0) + return ret; + + ret = convert_perf_probe_events(pevs, npevs); + if (ret < 0) + goto out_cleanup; + + if (params.command == 'D') { /* it shows definition */ + ret = show_probe_trace_events(pevs, npevs); + goto out_cleanup; + } + + ret = apply_perf_probe_events(pevs, npevs); + if (ret < 0) + goto out_cleanup; + + for (i = k = 0; i < npevs; i++) + k += pevs[i].ntevs; + + pr_info("Added new event%s\n", (k > 1) ? "s:" : ":"); + for (i = 0; i < npevs; i++) { + struct perf_probe_event *pev = &pevs[i]; + + for (k = 0; k < pev->ntevs; k++) { + struct probe_trace_event *tev = &pev->tevs[k]; + /* Skipped events have no event name */ + if (!tev->event) + continue; + + /* We use tev's name for showing new events */ + show_perf_probe_event(tev->group, tev->event, pev, + tev->point.module, false); + + /* Save the last valid name */ + event = tev->event; + group = tev->group; + } + } + + /* Note that it is possible to skip all events because of blacklist */ + if (event) { + /* Show how to use the event. */ + pr_info("\nYou can now use it in all perf tools, such as:\n\n"); + pr_info("\tperf record -e %s:%s -aR sleep 1\n\n", group, event); + } + +out_cleanup: + cleanup_perf_probe_events(pevs, npevs); + exit_probe_symbol_maps(); + return ret; +} + +static int del_perf_probe_caches(struct strfilter *filter) +{ + struct probe_cache *cache; + struct strlist *bidlist; + struct str_node *nd; + int ret; + + bidlist = build_id_cache__list_all(false); + if (!bidlist) { + ret = -errno; + pr_debug("Failed to get buildids: %d\n", ret); + return ret ?: -ENOMEM; + } + + strlist__for_each_entry(nd, bidlist) { + cache = probe_cache__new(nd->s, NULL); + if (!cache) + continue; + if (probe_cache__filter_purge(cache, filter) < 0 || + probe_cache__commit(cache) < 0) + pr_warning("Failed to remove entries for %s\n", nd->s); + probe_cache__delete(cache); + } + return 0; +} + +static int perf_del_probe_events(struct strfilter *filter) +{ + int ret, ret2, ufd = -1, kfd = -1; + char *str = strfilter__string(filter); + struct strlist *klist = NULL, *ulist = NULL; + struct str_node *ent; + + if (!str) + return -EINVAL; + + pr_debug("Delete filter: \'%s\'\n", str); + + if (probe_conf.cache) + return del_perf_probe_caches(filter); + + /* Get current event names */ + ret = probe_file__open_both(&kfd, &ufd, PF_FL_RW); + if (ret < 0) + goto out; + + klist = strlist__new(NULL, NULL); + ulist = strlist__new(NULL, NULL); + if (!klist || !ulist) { + ret = -ENOMEM; + goto out; + } + + ret = probe_file__get_events(kfd, filter, klist); + if (ret == 0) { + strlist__for_each_entry(ent, klist) + pr_info("Removed event: %s\n", ent->s); + + ret = probe_file__del_strlist(kfd, klist); + if (ret < 0) + goto error; + } else if (ret == -ENOMEM) + goto error; + + ret2 = probe_file__get_events(ufd, filter, ulist); + if (ret2 == 0) { + strlist__for_each_entry(ent, ulist) + pr_info("Removed event: %s\n", ent->s); + + ret2 = probe_file__del_strlist(ufd, ulist); + if (ret2 < 0) + goto error; + } else if (ret2 == -ENOMEM) + goto error; + + if (ret == -ENOENT && ret2 == -ENOENT) + pr_warning("\"%s\" does not hit any event.\n", str); + else + ret = 0; + +error: + if (kfd >= 0) + close(kfd); + if (ufd >= 0) + close(ufd); +out: + strlist__delete(klist); + strlist__delete(ulist); + free(str); + + return ret; +} + +#ifdef HAVE_DWARF_SUPPORT +#define PROBEDEF_STR \ + "[EVENT=]FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT [[NAME=]ARG ...]" +#else +#define PROBEDEF_STR "[EVENT=]FUNC[+OFF|%return] [[NAME=]ARG ...]" +#endif + + +static int +__cmd_probe(int argc, const char **argv) +{ + const char * const probe_usage[] = { + "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]", + "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]", + "perf probe [<options>] --del '[GROUP:]EVENT' ...", + "perf probe --list [GROUP:]EVENT ...", +#ifdef HAVE_DWARF_SUPPORT + "perf probe [<options>] --line 'LINEDESC'", + "perf probe [<options>] --vars 'PROBEPOINT'", +#endif + "perf probe [<options>] --funcs", + NULL + }; + struct option options[] = { + OPT_INCR('v', "verbose", &verbose, + "be more verbose (show parsed arguments, etc)"), + OPT_BOOLEAN('q', "quiet", ¶ms.quiet, + "be quiet (do not show any messages)"), + OPT_CALLBACK_DEFAULT('l', "list", NULL, "[GROUP:]EVENT", + "list up probe events", + opt_set_filter_with_command, DEFAULT_LIST_FILTER), + OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.", + opt_set_filter_with_command), + OPT_CALLBACK('a', "add", NULL, PROBEDEF_STR, + "probe point definition, where\n" + "\t\tGROUP:\tGroup name (optional)\n" + "\t\tEVENT:\tEvent name\n" + "\t\tFUNC:\tFunction name\n" + "\t\tOFF:\tOffset from function entry (in byte)\n" + "\t\t%return:\tPut the probe at function return\n" +#ifdef HAVE_DWARF_SUPPORT + "\t\tSRC:\tSource code path\n" + "\t\tRL:\tRelative line number from function entry.\n" + "\t\tAL:\tAbsolute line number in file.\n" + "\t\tPT:\tLazy expression of line code.\n" + "\t\tARG:\tProbe argument (local variable name or\n" + "\t\t\tkprobe-tracer argument format.)\n", +#else + "\t\tARG:\tProbe argument (kprobe-tracer argument format.)\n", +#endif + opt_add_probe_event), + OPT_CALLBACK('D', "definition", NULL, PROBEDEF_STR, + "Show trace event definition of given traceevent for k/uprobe_events.", + opt_add_probe_event), + OPT_BOOLEAN('f', "force", &probe_conf.force_add, "forcibly add events" + " with existing name"), + OPT_CALLBACK('L', "line", NULL, + "FUNC[:RLN[+NUM|-RLN2]]|SRC:ALN[+NUM|-ALN2]", + "Show source code lines.", opt_show_lines), + OPT_CALLBACK('V', "vars", NULL, + "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT", + "Show accessible variables on PROBEDEF", opt_show_vars), + OPT_BOOLEAN('\0', "externs", &probe_conf.show_ext_vars, + "Show external variables too (with --vars only)"), + OPT_BOOLEAN('\0', "range", &probe_conf.show_location_range, + "Show variables location range in scope (with --vars only)"), + OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name, + "file", "vmlinux pathname"), + OPT_STRING('s', "source", &symbol_conf.source_prefix, + "directory", "path to kernel source"), + OPT_BOOLEAN('\0', "no-inlines", &probe_conf.no_inlines, + "Don't search inlined functions"), + OPT__DRY_RUN(&probe_event_dry_run), + OPT_INTEGER('\0', "max-probes", &probe_conf.max_probes, + "Set how many probe points can be found for a probe."), + OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]", + "Show potential probe-able functions.", + opt_set_filter_with_command, DEFAULT_FUNC_FILTER), + OPT_CALLBACK('\0', "filter", NULL, + "[!]FILTER", "Set a filter (with --vars/funcs only)\n" + "\t\t\t(default: \"" DEFAULT_VAR_FILTER "\" for --vars,\n" + "\t\t\t \"" DEFAULT_FUNC_FILTER "\" for --funcs)", + opt_set_filter), + OPT_CALLBACK('x', "exec", NULL, "executable|path", + "target executable name or path", opt_set_target), + OPT_CALLBACK('m', "module", NULL, "modname|path", + "target module name (for online) or path (for offline)", + opt_set_target), + OPT_BOOLEAN(0, "demangle", &symbol_conf.demangle, + "Enable symbol demangling"), + OPT_BOOLEAN(0, "demangle-kernel", &symbol_conf.demangle_kernel, + "Enable kernel symbol demangling"), + OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"), + OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory", + "Look for files with symbols relative to this directory"), + OPT_CALLBACK(0, "target-ns", NULL, "pid", + "target pid for namespace contexts", opt_set_target_ns), + OPT_END() + }; + int ret; + + set_option_flag(options, 'a', "add", PARSE_OPT_EXCLUSIVE); + set_option_flag(options, 'd', "del", PARSE_OPT_EXCLUSIVE); + set_option_flag(options, 'D', "definition", PARSE_OPT_EXCLUSIVE); + set_option_flag(options, 'l', "list", PARSE_OPT_EXCLUSIVE); +#ifdef HAVE_DWARF_SUPPORT + set_option_flag(options, 'L', "line", PARSE_OPT_EXCLUSIVE); + set_option_flag(options, 'V', "vars", PARSE_OPT_EXCLUSIVE); +#else +# define set_nobuild(s, l, c) set_option_nobuild(options, s, l, "NO_DWARF=1", c) + set_nobuild('L', "line", false); + set_nobuild('V', "vars", false); + set_nobuild('\0', "externs", false); + set_nobuild('\0', "range", false); + set_nobuild('k', "vmlinux", true); + set_nobuild('s', "source", true); + set_nobuild('\0', "no-inlines", true); +# undef set_nobuild +#endif + set_option_flag(options, 'F', "funcs", PARSE_OPT_EXCLUSIVE); + + argc = parse_options(argc, argv, options, probe_usage, + PARSE_OPT_STOP_AT_NON_OPTION); + if (argc > 0) { + if (strcmp(argv[0], "-") == 0) { + usage_with_options_msg(probe_usage, options, + "'-' is not supported.\n"); + } + if (params.command && params.command != 'a') { + usage_with_options_msg(probe_usage, options, + "another command except --add is set.\n"); + } + ret = parse_probe_event_argv(argc, argv); + if (ret < 0) { + pr_err_with_code(" Error: Command Parse Error.", ret); + return ret; + } + params.command = 'a'; + } + + if (params.quiet) { + if (verbose != 0) { + pr_err(" Error: -v and -q are exclusive.\n"); + return -EINVAL; + } + verbose = -1; + } + + if (probe_conf.max_probes == 0) + probe_conf.max_probes = MAX_PROBES; + + /* + * Only consider the user's kernel image path if given. + */ + symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL); + + /* + * Except for --list, --del and --add, other command doesn't depend + * nor change running kernel. So if user gives offline vmlinux, + * ignore its buildid. + */ + if (!strchr("lda", params.command) && symbol_conf.vmlinux_name) + symbol_conf.ignore_vmlinux_buildid = true; + + switch (params.command) { + case 'l': + if (params.uprobes) { + pr_err(" Error: Don't use --list with --exec.\n"); + parse_options_usage(probe_usage, options, "l", true); + parse_options_usage(NULL, options, "x", true); + return -EINVAL; + } + ret = show_perf_probe_events(params.filter); + if (ret < 0) + pr_err_with_code(" Error: Failed to show event list.", ret); + return ret; + case 'F': + ret = show_available_funcs(params.target, params.nsi, + params.filter, params.uprobes); + if (ret < 0) + pr_err_with_code(" Error: Failed to show functions.", ret); + return ret; +#ifdef HAVE_DWARF_SUPPORT + case 'L': + ret = show_line_range(¶ms.line_range, params.target, + params.nsi, params.uprobes); + if (ret < 0) + pr_err_with_code(" Error: Failed to show lines.", ret); + return ret; + case 'V': + if (!params.filter) + params.filter = strfilter__new(DEFAULT_VAR_FILTER, + NULL); + + ret = show_available_vars(params.events, params.nevents, + params.filter); + if (ret < 0) + pr_err_with_code(" Error: Failed to show vars.", ret); + return ret; +#endif + case 'd': + ret = perf_del_probe_events(params.filter); + if (ret < 0) { + pr_err_with_code(" Error: Failed to delete events.", ret); + return ret; + } + break; + case 'D': + case 'a': + + /* Ensure the last given target is used */ + if (params.target && !params.target_used) { + pr_err(" Error: -x/-m must follow the probe definitions.\n"); + parse_options_usage(probe_usage, options, "m", true); + parse_options_usage(NULL, options, "x", true); + return -EINVAL; + } + + ret = perf_add_probe_events(params.events, params.nevents); + if (ret < 0) { + + /* + * When perf_add_probe_events() fails it calls + * cleanup_perf_probe_events(pevs, npevs), i.e. + * cleanup_perf_probe_events(params.events, params.nevents), which + * will call clear_perf_probe_event(), so set nevents to zero + * to avoid cleanup_params() to call clear_perf_probe_event() again + * on the same pevs. + */ + params.nevents = 0; + pr_err_with_code(" Error: Failed to add events.", ret); + return ret; + } + break; + default: + usage_with_options(probe_usage, options); + } + return 0; +} + +int cmd_probe(int argc, const char **argv) +{ + int ret; + + ret = init_params(); + if (!ret) { + ret = __cmd_probe(argc, argv); + cleanup_params(); + } + + return ret < 0 ? ret : 0; +} |