1 files changed, 242 insertions, 0 deletions
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
new file mode 100644
index 0000000..a58e11b
--- /dev/null
+++ b/tools/perf/builtin-probe.c
@@ -0,0 +1,242 @@
+/*
+ * builtin-probe.c
+ *
+ * Builtin probe command: Set up probe events by C expression
+ *
+ * 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 "perf.h"
+#include "builtin.h"
+#include "util/util.h"
+#include "util/event.h"
+#include "util/debug.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"	/* For debugfs_path */
+#include "util/probe-finder.h"
+#include "util/probe-event.h"
+
+/* Default vmlinux search paths */
+#define NR_SEARCH_PATH 3
+const char *default_search_path[NR_SEARCH_PATH] = {
+"/lib/modules/%s/build/vmlinux",		/* Custom build kernel */
+"/usr/lib/debug/lib/modules/%s/vmlinux",	/* Red Hat debuginfo */
+"/boot/vmlinux-debug-%s",			/* Ubuntu */
+};
+
+#define MAX_PATH_LEN 256
+#define MAX_PROBES 128
+
+/* Session management structure */
+static struct {
+	char *vmlinux;
+	char *release;
+	int need_dwarf;
+	int nr_probe;
+	struct probe_point probes[MAX_PROBES];
+} session;
+
+static bool listing;
+
+/* Parse an event definition. Note that any error must die. */
+static void parse_probe_event(const char *str)
+{
+	struct probe_point *pp = &session.probes[session.nr_probe];
+
+	pr_debug("probe-definition(%d): %s\n", session.nr_probe, str);
+	if (++session.nr_probe == MAX_PROBES)
+		die("Too many probes (> %d) are specified.", MAX_PROBES);
+
+	/* Parse perf-probe event into probe_point */
+	session.need_dwarf = parse_perf_probe_event(str, pp);
+
+	pr_debug("%d arguments\n", pp->nr_args);
+}
+
+static int opt_add_probe_event(const struct option *opt __used,
+			      const char *str, int unset __used)
+{
+	if (str)
+		parse_probe_event(str);
+	return 0;
+}
+
+#ifndef NO_LIBDWARF
+static int open_default_vmlinux(void)
+{
+	struct utsname uts;
+	char fname[MAX_PATH_LEN];
+	int fd, ret, i;
+
+	ret = uname(&uts);
+	if (ret) {
+		pr_debug("uname() failed.\n");
+		return -errno;
+	}
+	session.release = uts.release;
+	for (i = 0; i < NR_SEARCH_PATH; i++) {
+		ret = snprintf(fname, MAX_PATH_LEN,
+			       default_search_path[i], session.release);
+		if (ret >= MAX_PATH_LEN || ret < 0) {
+			pr_debug("Filename(%d,%s) is too long.\n", i,
+				uts.release);
+			errno = E2BIG;
+			return -E2BIG;
+		}
+		pr_debug("try to open %s\n", fname);
+		fd = open(fname, O_RDONLY);
+		if (fd >= 0)
+			break;
+	}
+	return fd;
+}
+#endif
+
+static const char * const probe_usage[] = {
+	"perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
+	"perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
+	"perf probe --list",
+	NULL
+};
+
+static const struct option options[] = {
+	OPT_BOOLEAN('v', "verbose", &verbose,
+		    "be more verbose (show parsed arguments, etc)"),
+#ifndef NO_LIBDWARF
+	OPT_STRING('k', "vmlinux", &session.vmlinux, "file",
+		"vmlinux/module pathname"),
+#endif
+	OPT_BOOLEAN('l', "list", &listing, "list up current probes"),
+	OPT_CALLBACK('a', "add", NULL,
+#ifdef NO_LIBDWARF
+		"FUNC[+OFFS|%return] [ARG ...]",
+#else
+		"FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]",
+#endif
+		"probe point definition, where\n"
+		"\t\tGRP:\tGroup name (optional)\n"
+		"\t\tNAME:\tEvent name\n"
+		"\t\tFUNC:\tFunction name\n"
+		"\t\tOFFS:\tOffset from function entry (in byte)\n"
+		"\t\t%return:\tPut the probe at function return\n"
+#ifdef NO_LIBDWARF
+		"\t\tARG:\tProbe argument (only \n"
+#else
+		"\t\tSRC:\tSource code path\n"
+		"\t\tRLN:\tRelative line number from function entry.\n"
+		"\t\tALN:\tAbsolute line number in file.\n"
+		"\t\tARG:\tProbe argument (local variable name or\n"
+#endif
+		"\t\t\tkprobe-tracer argument format.)\n",
+		opt_add_probe_event),
+	OPT_END()
+};
+
+int cmd_probe(int argc, const char **argv, const char *prefix __used)
+{
+	int i, j, ret;
+#ifndef NO_LIBDWARF
+	int fd;
+#endif
+	struct probe_point *pp;
+
+	argc = parse_options(argc, argv, options, probe_usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+	for (i = 0; i < argc; i++)
+		parse_probe_event(argv[i]);
+
+	if ((session.nr_probe == 0 && !listing) ||
+	    (session.nr_probe != 0 && listing))
+		usage_with_options(probe_usage, options);
+
+	if (listing) {
+		show_perf_probe_events();
+		return 0;
+	}
+
+	if (session.need_dwarf)
+#ifdef NO_LIBDWARF
+		die("Debuginfo-analysis is not supported");
+#else	/* !NO_LIBDWARF */
+		pr_debug("Some probes require debuginfo.\n");
+
+	if (session.vmlinux)
+		fd = open(session.vmlinux, O_RDONLY);
+	else
+		fd = open_default_vmlinux();
+	if (fd < 0) {
+		if (session.need_dwarf)
+			die("Could not open vmlinux/module file.");
+
+		pr_warning("Could not open vmlinux/module file."
+			   " Try to use symbols.\n");
+		goto end_dwarf;
+	}
+
+	/* Searching probe points */
+	for (j = 0; j < session.nr_probe; j++) {
+		pp = &session.probes[j];
+		if (pp->found)
+			continue;
+
+		lseek(fd, SEEK_SET, 0);
+		ret = find_probepoint(fd, pp);
+		if (ret < 0) {
+			if (session.need_dwarf)
+				die("Could not analyze debuginfo.");
+
+			pr_warning("An error occurred in debuginfo analysis. Try to use symbols.\n");
+			break;
+		}
+		if (ret == 0)	/* No error but failed to find probe point. */
+			die("No probe point found.");
+	}
+	close(fd);
+
+end_dwarf:
+#endif /* !NO_LIBDWARF */
+
+	/* Synthesize probes without dwarf */
+	for (j = 0; j < session.nr_probe; j++) {
+		pp = &session.probes[j];
+		if (pp->found)	/* This probe is already found. */
+			continue;
+
+		ret = synthesize_trace_kprobe_event(pp);
+		if (ret == -E2BIG)
+			die("probe point definition becomes too long.");
+		else if (ret < 0)
+			die("Failed to synthesize a probe point.");
+	}
+
+	/* Settng up probe points */
+	add_trace_kprobe_events(session.probes, session.nr_probe);
+	return 0;
+}
+