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 <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091201001958.10235.90243.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
new file mode 100644
index 0000000..7335a3b
--- /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 <mhiramat@redhat.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.
+ *
+ * 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 <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>
+
+#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;
+ /*
+ * <Syntax>
+ * 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);
+}