1 files changed, 309 insertions, 0 deletions
diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
new file mode 100644
index 000000000000..c1e6774fd3ed
--- /dev/null
+++ b/tools/perf/builtin-probe.c
@@ -0,0 +1,309 @@
+/*
+ * 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/strlist.h"
+#include "util/event.h"
+#include "util/debug.h"
+#include "util/debugfs.h"
+#include "util/symbol.h"
+#include "util/thread.h"
+#include "util/session.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"	/* For debugfs_path */
+#include "util/probe-finder.h"
+#include "util/probe-event.h"
+
+#define MAX_PATH_LEN 256
+#define MAX_PROBES 128
+
+/* Session management structure */
+static struct {
+	bool need_dwarf;
+	bool list_events;
+	bool force_add;
+	int nr_probe;
+	struct probe_point probes[MAX_PROBES];
+	struct strlist *dellist;
+	struct perf_session *psession;
+	struct map *kmap;
+} session;
+
+
+/* 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 */
+	parse_perf_probe_event(str, pp, &session.need_dwarf);
+
+	pr_debug("%d arguments\n", pp->nr_args);
+}
+
+static void parse_probe_event_argv(int argc, const char **argv)
+{
+	int i, len;
+	char *buf;
+
+	/* Bind up rest arguments */
+	len = 0;
+	for (i = 0; i < argc; i++)
+		len += strlen(argv[i]) + 1;
+	buf = zalloc(len + 1);
+	if (!buf)
+		die("Failed to allocate memory for binding arguments.");
+	len = 0;
+	for (i = 0; i < argc; i++)
+		len += sprintf(&buf[len], "%s ", argv[i]);
+	parse_probe_event(buf);
+	free(buf);
+}
+
+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;
+}
+
+static int opt_del_probe_event(const struct option *opt __used,
+			       const char *str, int unset __used)
+{
+	if (str) {
+		if (!session.dellist)
+			session.dellist = strlist__new(true, NULL);
+		strlist__add(session.dellist, str);
+	}
+	return 0;
+}
+
+/* Currently just checking function name from symbol map */
+static void evaluate_probe_point(struct probe_point *pp)
+{
+	struct symbol *sym;
+	sym = map__find_symbol_by_name(session.kmap, pp->function,
+				       session.psession, NULL);
+	if (!sym)
+		die("Kernel symbol \'%s\' not found - probe not added.",
+		    pp->function);
+}
+
+#ifndef NO_LIBDWARF
+static int open_vmlinux(void)
+{
+	if (map__load(session.kmap, session.psession, NULL) < 0) {
+		pr_debug("Failed to load kernel map.\n");
+		return -EINVAL;
+	}
+	pr_debug("Try to open %s\n", session.kmap->dso->long_name);
+	return open(session.kmap->dso->long_name, O_RDONLY);
+}
+#endif
+
+static 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",
+	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", &symbol_conf.vmlinux_name,
+		   "file", "vmlinux pathname"),
+#endif
+	OPT_BOOLEAN('l', "list", &session.list_events,
+		    "list up current probe events"),
+	OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
+		opt_del_probe_event),
+	OPT_CALLBACK('a', "add", NULL,
+#ifdef NO_LIBDWARF
+		"[EVENT=]FUNC[+OFFS|%return] [ARG ...]",
+#else
+		"[EVENT=]FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]",
+#endif
+		"probe point definition, where\n"
+		"\t\tGROUP:\tGroup name (optional)\n"
+		"\t\tEVENT:\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_BOOLEAN('f', "force", &session.force_add, "forcibly add events"
+		    " with existing name"),
+	OPT_END()
+};
+
+int cmd_probe(int argc, const char **argv, const char *prefix __used)
+{
+	int i, 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);
+	if (argc > 0) {
+		if (strcmp(argv[0], "-") == 0) {
+			pr_warning("  Error: '-' is not supported.\n");
+			usage_with_options(probe_usage, options);
+		}
+		parse_probe_event_argv(argc, argv);
+	}
+
+	if ((!session.nr_probe && !session.dellist && !session.list_events))
+		usage_with_options(probe_usage, options);
+
+	if (debugfs_valid_mountpoint(debugfs_path) < 0)
+		die("Failed to find debugfs path.");
+
+	if (session.list_events) {
+		if (session.nr_probe != 0 || session.dellist) {
+			pr_warning("  Error: Don't use --list with"
+				   " --add/--del.\n");
+			usage_with_options(probe_usage, options);
+		}
+		show_perf_probe_events();
+		return 0;
+	}
+
+	if (session.dellist) {
+		del_trace_kprobe_events(session.dellist);
+		strlist__delete(session.dellist);
+		if (session.nr_probe == 0)
+			return 0;
+	}
+
+	/* Initialize symbol maps for vmlinux */
+	symbol_conf.sort_by_name = true;
+	if (symbol_conf.vmlinux_name == NULL)
+		symbol_conf.try_vmlinux_path = true;
+	if (symbol__init() < 0)
+		die("Failed to init symbol map.");
+	session.psession = perf_session__new(NULL, O_WRONLY, false);
+	if (session.psession == NULL)
+		die("Failed to init perf_session.");
+	session.kmap = map_groups__find_by_name(&session.psession->kmaps,
+						MAP__FUNCTION,
+						"[kernel.kallsyms]");
+	if (!session.kmap)
+		die("Could not find kernel map.\n");
+
+	if (session.need_dwarf)
+#ifdef NO_LIBDWARF
+		die("Debuginfo-analysis is not supported");
+#else	/* !NO_LIBDWARF */
+		pr_debug("Some probes require debuginfo.\n");
+
+	fd = open_vmlinux();
+	if (fd < 0) {
+		if (session.need_dwarf)
+			die("Could not open debuginfo file.");
+
+		pr_debug("Could not open vmlinux/module file."
+			 " Try to use symbols.\n");
+		goto end_dwarf;
+	}
+
+	/* Searching probe points */
+	for (i = 0; i < session.nr_probe; i++) {
+		pp = &session.probes[i];
+		if (pp->found)
+			continue;
+
+		lseek(fd, SEEK_SET, 0);
+		ret = find_probepoint(fd, pp);
+		if (ret > 0)
+			continue;
+		if (ret == 0) {	/* No error but failed to find probe point. */
+			synthesize_perf_probe_point(pp);
+			die("Probe point '%s' not found. - probe not added.",
+			    pp->probes[0]);
+		}
+		/* Error path */
+		if (session.need_dwarf) {
+			if (ret == -ENOENT)
+				pr_warning("No dwarf info found in the vmlinux - please rebuild with CONFIG_DEBUG_INFO=y.\n");
+			die("Could not analyze debuginfo.");
+		}
+		pr_debug("An error occurred in debuginfo analysis."
+			 " Try to use symbols.\n");
+		break;
+	}
+	close(fd);
+
+end_dwarf:
+#endif /* !NO_LIBDWARF */
+
+	/* Synthesize probes without dwarf */
+	for (i = 0; i < session.nr_probe; i++) {
+		pp = &session.probes[i];
+		if (pp->found)	/* This probe is already found. */
+			continue;
+
+		evaluate_probe_point(pp);
+		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,
+				session.force_add);
+	return 0;
+}
+