From 50656eec82684d03add0f4f4b4875a20bd8f9755 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 30 Nov 2009 19:19:58 -0500 Subject: perf probe: Move probe event utility functions to probe-event.c Split probe event (kprobe-events and perf probe events) utility functions from builtin-probe.c to probe-event.c. Signed-off-by: Masami Hiramatsu Cc: systemtap Cc: DLE Cc: Steven Rostedt Cc: Jim Keniston Cc: Ananth N Mavinakayanahalli Cc: Christoph Hellwig Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Jason Baron Cc: K.Prasad Cc: Peter Zijlstra Cc: Srikar Dronamraju Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker LKML-Reference: <20091201001958.10235.90243.stgit@harusame> Signed-off-by: Ingo Molnar --- tools/perf/util/probe-event.c | 273 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 273 insertions(+) create mode 100644 tools/perf/util/probe-event.c (limited to 'tools/perf/util/probe-event.c') diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c new file mode 100644 index 000000000000..7335a3b5e494 --- /dev/null +++ b/tools/perf/util/probe-event.c @@ -0,0 +1,273 @@ +/* + * probe-event.c : perf-probe definition to kprobe_events format converter + * + * Written by Masami Hiramatsu + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#undef _GNU_SOURCE +#include "event.h" +#include "debug.h" +#include "parse-events.h" /* For debugfs_path */ +#include "probe-event.h" + +#define MAX_CMDLEN 256 +#define MAX_PROBE_ARGS 128 +#define PERFPROBE_GROUP "probe" + +#define semantic_error(msg ...) die("Semantic error :" msg) + +/* Parse probepoint definition. */ +static void parse_perf_probe_probepoint(char *arg, struct probe_point *pp) +{ + char *ptr, *tmp; + char c, nc = 0; + /* + * + * perf probe SRC:LN + * perf probe FUNC[+OFFS|%return][@SRC] + */ + + ptr = strpbrk(arg, ":+@%"); + if (ptr) { + nc = *ptr; + *ptr++ = '\0'; + } + + /* Check arg is function or file and copy it */ + if (strchr(arg, '.')) /* File */ + pp->file = strdup(arg); + else /* Function */ + pp->function = strdup(arg); + DIE_IF(pp->file == NULL && pp->function == NULL); + + /* Parse other options */ + while (ptr) { + arg = ptr; + c = nc; + ptr = strpbrk(arg, ":+@%"); + if (ptr) { + nc = *ptr; + *ptr++ = '\0'; + } + switch (c) { + case ':': /* Line number */ + pp->line = strtoul(arg, &tmp, 0); + if (*tmp != '\0') + semantic_error("There is non-digit charactor" + " in line number."); + break; + case '+': /* Byte offset from a symbol */ + pp->offset = strtoul(arg, &tmp, 0); + if (*tmp != '\0') + semantic_error("There is non-digit charactor" + " in offset."); + break; + case '@': /* File name */ + if (pp->file) + semantic_error("SRC@SRC is not allowed."); + pp->file = strdup(arg); + DIE_IF(pp->file == NULL); + if (ptr) + semantic_error("@SRC must be the last " + "option."); + break; + case '%': /* Probe places */ + if (strcmp(arg, "return") == 0) { + pp->retprobe = 1; + } else /* Others not supported yet */ + semantic_error("%%%s is not supported.", arg); + break; + default: + DIE_IF("Program has a bug."); + break; + } + } + + /* Exclusion check */ + if (pp->line && pp->offset) + semantic_error("Offset can't be used with line number."); + + if (!pp->line && pp->file && !pp->function) + semantic_error("File always requires line number."); + + if (pp->offset && !pp->function) + semantic_error("Offset requires an entry function."); + + if (pp->retprobe && !pp->function) + semantic_error("Return probe requires an entry function."); + + if ((pp->offset || pp->line) && pp->retprobe) + semantic_error("Offset/Line can't be used with return probe."); + + pr_debug("symbol:%s file:%s line:%d offset:%d, return:%d\n", + pp->function, pp->file, pp->line, pp->offset, pp->retprobe); +} + +/* Parse perf-probe event definition */ +int parse_perf_probe_event(const char *str, struct probe_point *pp) +{ + char *argv[MAX_PROBE_ARGS + 1]; /* probe + args */ + int argc, i, need_dwarf = 0; + + /* Separate arguments, similar to argv_split */ + argc = 0; + do { + /* Skip separators */ + while (isspace(*str)) + str++; + + /* Add an argument */ + if (*str != '\0') { + const char *s = str; + /* Check the limit number of arguments */ + if (argc == MAX_PROBE_ARGS + 1) + semantic_error("Too many arguments"); + + /* Skip the argument */ + while (!isspace(*str) && *str != '\0') + str++; + + /* Duplicate the argument */ + argv[argc] = strndup(s, str - s); + if (argv[argc] == NULL) + die("strndup"); + pr_debug("argv[%d]=%s\n", argc, argv[argc]); + argc++; + } + } while (*str != '\0'); + if (!argc) + semantic_error("An empty argument."); + + /* Parse probe point */ + parse_perf_probe_probepoint(argv[0], pp); + free(argv[0]); + if (pp->file || pp->line) + need_dwarf = 1; + + /* Copy arguments */ + pp->nr_args = argc - 1; + if (pp->nr_args > 0) { + pp->args = (char **)malloc(sizeof(char *) * pp->nr_args); + if (!pp->args) + die("malloc"); + memcpy(pp->args, &argv[1], sizeof(char *) * pp->nr_args); + } + + /* Ensure return probe has no C argument */ + for (i = 0; i < pp->nr_args; i++) + if (is_c_varname(pp->args[i])) { + if (pp->retprobe) + semantic_error("You can't specify local" + " variable for kretprobe"); + need_dwarf = 1; + } + + return need_dwarf; +} + +int synthesize_trace_kprobe_event(struct probe_point *pp) +{ + char *buf; + int i, len, ret; + + 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) + 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) + goto error; + len += ret; + } + pp->found = 1; + + return pp->found; +error: + free(pp->probes[0]); + if (ret > 0) + ret = -E2BIG; + + return ret; +} + +static int write_trace_kprobe_event(int fd, const char *buf) +{ + int ret; + + ret = write(fd, buf, strlen(buf)); + if (ret <= 0) + die("Failed to create event."); + else + printf("Added new event: %s\n", buf); + + return ret; +} + +void add_trace_kprobe_events(struct probe_point *probes, int nr_probes) +{ + int i, j, fd; + 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)); + } + + for (j = 0; j < nr_probes; j++) { + pp = probes + j; + if (pp->found == 1) { + snprintf(buf, MAX_CMDLEN, "%c:%s/%s_%x %s\n", + pp->retprobe ? 'r' : 'p', PERFPROBE_GROUP, + pp->function, pp->offset, pp->probes[0]); + write_trace_kprobe_event(fd, buf); + } else + for (i = 0; i < pp->found; i++) { + snprintf(buf, MAX_CMDLEN, "%c:%s/%s_%x_%d %s\n", + pp->retprobe ? 'r' : 'p', + PERFPROBE_GROUP, + pp->function, pp->offset, i, + pp->probes[i]); + write_trace_kprobe_event(fd, buf); + } + } + close(fd); +} -- cgit v1.2.2