diff options
Diffstat (limited to 'tools/perf/util/probe-event.c')
| -rw-r--r-- | tools/perf/util/probe-event.c | 231 |
1 files changed, 214 insertions, 17 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index e3a683ab976f..7f4f288c642e 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -29,10 +29,13 @@ #include <unistd.h> #include <stdlib.h> #include <string.h> +#include <stdarg.h> +#include <limits.h> #undef _GNU_SOURCE #include "event.h" #include "string.h" +#include "strlist.h" #include "debug.h" #include "parse-events.h" /* For debugfs_path */ #include "probe-event.h" @@ -43,6 +46,19 @@ #define semantic_error(msg ...) die("Semantic error :" msg) +/* If there is no space to write, returns -E2BIG. */ +static int e_snprintf(char *str, size_t size, const char *format, ...) +{ + int ret; + va_list ap; + va_start(ap, format); + ret = vsnprintf(str, size, format, ap); + va_end(ap); + if (ret >= (int)size) + ret = -E2BIG; + return ret; +} + /* Parse probepoint definition. */ static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp) { @@ -166,6 +182,103 @@ int parse_perf_probe_event(const char *str, struct probe_point *pp) return need_dwarf; } +/* Parse kprobe_events event into struct probe_point */ +void parse_trace_kprobe_event(const char *str, char **group, char **event, + struct probe_point *pp) +{ + char pr; + char *p; + int ret, i, argc; + char **argv; + + pr_debug("Parsing kprobe_events: %s\n", str); + argv = argv_split(str, &argc); + if (!argv) + die("argv_split failed."); + if (argc < 2) + semantic_error("Too less arguments."); + + /* Scan event and group name. */ + ret = sscanf(argv[0], "%c:%m[^/ \t]/%m[^ \t]", + &pr, group, event); + if (ret != 3) + semantic_error("Failed to parse event name: %s", argv[0]); + pr_debug("Group:%s Event:%s probe:%c\n", *group, *event, pr); + + if (!pp) + goto end; + + pp->retprobe = (pr == 'r'); + + /* Scan function name and offset */ + ret = sscanf(argv[1], "%m[^+]+%d", &pp->function, &pp->offset); + if (ret == 1) + pp->offset = 0; + + /* kprobe_events doesn't have this information */ + pp->line = 0; + pp->file = NULL; + + pp->nr_args = argc - 2; + pp->args = zalloc(sizeof(char *) * pp->nr_args); + for (i = 0; i < pp->nr_args; i++) { + p = strchr(argv[i + 2], '='); + if (p) /* We don't need which register is assigned. */ + *p = '\0'; + pp->args[i] = strdup(argv[i + 2]); + if (!pp->args[i]) + die("Failed to copy argument."); + } + +end: + argv_free(argv); +} + +int synthesize_perf_probe_event(struct probe_point *pp) +{ + char *buf; + char offs[64] = "", line[64] = ""; + int i, len, ret; + + pp->probes[0] = buf = zalloc(MAX_CMDLEN); + if (!buf) + die("Failed to allocate memory by zalloc."); + if (pp->offset) { + ret = e_snprintf(offs, 64, "+%d", pp->offset); + if (ret <= 0) + goto error; + } + if (pp->line) { + ret = e_snprintf(line, 64, ":%d", pp->line); + if (ret <= 0) + goto error; + } + + if (pp->function) + ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->function, + offs, pp->retprobe ? "%return" : "", line); + else + ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->file, line); + if (ret <= 0) + goto error; + len = ret; + + for (i = 0; i < pp->nr_args; i++) { + ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s", + pp->args[i]); + if (ret <= 0) + goto error; + len += ret; + } + pp->found = 1; + + return pp->found; +error: + free(pp->probes[0]); + + return ret; +} + int synthesize_trace_kprobe_event(struct probe_point *pp) { char *buf; @@ -174,15 +287,15 @@ int synthesize_trace_kprobe_event(struct probe_point *pp) pp->probes[0] = buf = zalloc(MAX_CMDLEN); if (!buf) die("Failed to allocate memory by zalloc."); - ret = snprintf(buf, MAX_CMDLEN, "%s+%d", pp->function, pp->offset); - if (ret <= 0 || ret >= MAX_CMDLEN) + ret = e_snprintf(buf, MAX_CMDLEN, "%s+%d", pp->function, pp->offset); + if (ret <= 0) goto error; len = ret; for (i = 0; i < pp->nr_args; i++) { - ret = snprintf(&buf[len], MAX_CMDLEN - len, " %s", - pp->args[i]); - if (ret <= 0 || ret >= MAX_CMDLEN - len) + ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s", + pp->args[i]); + if (ret <= 0) goto error; len += ret; } @@ -191,12 +304,105 @@ int synthesize_trace_kprobe_event(struct probe_point *pp) return pp->found; error: free(pp->probes[0]); - if (ret > 0) - ret = -E2BIG; return ret; } +static int open_kprobe_events(int flags, int mode) +{ + char buf[PATH_MAX]; + int ret; + + ret = e_snprintf(buf, PATH_MAX, "%s/../kprobe_events", debugfs_path); + if (ret < 0) + die("Failed to make kprobe_events path."); + + ret = open(buf, flags, mode); + if (ret < 0) { + if (errno == ENOENT) + die("kprobe_events file does not exist -" + " please rebuild with CONFIG_KPROBE_TRACER."); + else + die("Could not open kprobe_events file: %s", + strerror(errno)); + } + return ret; +} + +/* Get raw string list of current kprobe_events */ +static struct strlist *get_trace_kprobe_event_rawlist(int fd) +{ + int ret, idx; + FILE *fp; + char buf[MAX_CMDLEN]; + char *p; + struct strlist *sl; + + sl = strlist__new(true, 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) + die("strlist__add failed: %s", strerror(-ret)); + } + fclose(fp); + + return sl; +} + +/* Free and zero clear probe_point */ +static void clear_probe_point(struct probe_point *pp) +{ + int i; + + if (pp->function) + free(pp->function); + if (pp->file) + free(pp->file); + for (i = 0; i < pp->nr_args; i++) + free(pp->args[i]); + if (pp->args) + free(pp->args); + for (i = 0; i < pp->found; i++) + free(pp->probes[i]); + memset(pp, 0, sizeof(pp)); +} + +/* List up current perf-probe events */ +void show_perf_probe_events(void) +{ + unsigned int i; + int fd; + char *group, *event; + struct probe_point pp; + struct strlist *rawlist; + struct str_node *ent; + + fd = open_kprobe_events(O_RDONLY, 0); + rawlist = get_trace_kprobe_event_rawlist(fd); + close(fd); + + for (i = 0; i < strlist__nr_entries(rawlist); i++) { + ent = strlist__entry(rawlist, i); + parse_trace_kprobe_event(ent->s, &group, &event, &pp); + synthesize_perf_probe_event(&pp); + printf("[%s:%s]\t%s\n", group, event, pp.probes[0]); + free(group); + free(event); + clear_probe_point(&pp); + } + + strlist__delete(rawlist); +} + static int write_trace_kprobe_event(int fd, const char *buf) { int ret; @@ -216,16 +422,7 @@ void add_trace_kprobe_events(struct probe_point *probes, int nr_probes) struct probe_point *pp; char buf[MAX_CMDLEN]; - snprintf(buf, MAX_CMDLEN, "%s/../kprobe_events", debugfs_path); - fd = open(buf, O_WRONLY, O_APPEND); - if (fd < 0) { - if (errno == ENOENT) - die("kprobe_events file does not exist -" - " please rebuild with CONFIG_KPROBE_TRACER."); - else - die("Could not open kprobe_events file: %s", - strerror(errno)); - } + fd = open_kprobe_events(O_WRONLY, O_APPEND); for (j = 0; j < nr_probes; j++) { pp = probes + j; |