[PATCH -tip v2 1/6] perf: Introduce perf sub command 'bts record'

[Akihiro Nagai <akihiro.nagai.hw@hitachi.com>]

Introduce the easy way to record bts log, 'perf bts record'.
This command can record the bts log while specified command is executing,
and save to the file "perf.data"

Usage:
  perf bts record <tracee command>

Example:
  # perf bts record ls -l
    (ls -l outputs)
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.007 MB perf.data (~320 samples) ]
  # ls
    perf.data

Changes in V2:
 - Update to the latest -tip tree
 - add bts explanation to the subcommand list

Signed-off-by: Akihiro Nagai <akihiro.nagai.hw@hitachi.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
---

 tools/perf/Documentation/perf-bts.txt |   24 +++++++++++++
 tools/perf/Makefile                   |    1 +
 tools/perf/builtin-bts.c              |   62 +++++++++++++++++++++++++++++++++
 tools/perf/builtin.h                  |    1 +
 tools/perf/command-list.txt           |    1 +
 tools/perf/perf.c                     |    1 +
 6 files changed, 90 insertions(+), 0 deletions(-)
 create mode 100644 tools/perf/Documentation/perf-bts.txt
 create mode 100644 tools/perf/builtin-bts.c

diff --git a/tools/perf/Documentation/perf-bts.txt b/tools/perf/Documentation/perf-bts.txt
new file mode 100644
index 0000000..55a2fe6
--- /dev/null
+++ b/tools/perf/Documentation/perf-bts.txt
@@ -0,0 +1,24 @@
+perf-bts(1)
+==============
+
+NAME
+----
+perf-bts - Record branch-trace-store log
+
+SYNOPSIS
+--------
+[verse]
+'perf bts' record <command>
+
+DESCRIPTION
+-----------
+This command can record branch-trace-store log.
+Branch-trace-store is a facility of processors. It can record
+address of branch to/from on every branch instruction and interrupt.
+
+'perf bts record <command>' records branch-trace-store log while specified
+command is executing. And, save to the file "perf.data".
+
+SEE ALSO
+--------
+linkperf:perf-record[1]
diff --git a/tools/perf/Makefile b/tools/perf/Makefile
index ac6692c..cd3a8df 100644
--- a/tools/perf/Makefile
+++ b/tools/perf/Makefile
@@ -502,6 +502,7 @@ BUILTIN_OBJS += $(OUTPUT)builtin-lock.o
 BUILTIN_OBJS += $(OUTPUT)builtin-kvm.o
 BUILTIN_OBJS += $(OUTPUT)builtin-test.o
 BUILTIN_OBJS += $(OUTPUT)builtin-inject.o
+BUILTIN_OBJS += $(OUTPUT)builtin-bts.o
 
 PERFLIBS = $(LIB_FILE)
 
diff --git a/tools/perf/builtin-bts.c b/tools/perf/builtin-bts.c
new file mode 100644
index 0000000..587cfad
--- /dev/null
+++ b/tools/perf/builtin-bts.c
@@ -0,0 +1,62 @@
+#include "builtin.h"
+#include "perf.h"
+#include "util/parse-options.h"
+
+static const char * const bts_usage[] = {
+	"perf bts record <command>",
+	NULL,
+};
+
+/* arguments to call 'perf record' */
+static const char * const record_args[] = {
+	"record",
+	"-f",
+	"-e", "branches:u",
+	"-c", "1",
+	"-d",
+};
+
+/* dummy struct option to call parse_options() */
+static const struct option bts_options[] = {
+	OPT_END()
+};
+
+static int __cmd_record(int argc, const char **argv)
+{
+	unsigned int rec_argc, i, j;
+	const char **rec_argv;
+	int rc;
+
+	/* prepare the arguments list to call 'perf record' */
+	rec_argc = ARRAY_SIZE(record_args) + argc - 1;
+	rec_argv = calloc(rec_argc + 1, sizeof(char *));
+
+	for (i = 0; i < ARRAY_SIZE(record_args); i++)
+		rec_argv[i] = record_args[i];
+
+	for (j = 1; j < (unsigned int)argc; j++, i++)
+		rec_argv[i] = argv[j];
+
+	BUG_ON(i != rec_argc);
+
+	/* call 'perf record' */
+	rc = cmd_record(i, rec_argv, NULL);
+
+	free(rec_argv);
+	return rc;
+}
+
+int cmd_bts(int argc, const char **argv, const char *prefix __used)
+{
+	argc = parse_options(argc, argv, bts_options, bts_usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+	if (!argc)
+		usage_with_options(bts_usage, bts_options);
+
+	if (!strncmp(argv[0], "record", 6))
+		return __cmd_record(argc, argv);
+	else
+		usage_with_options(bts_usage, bts_options);
+
+	return 0;
+}
diff --git a/tools/perf/builtin.h b/tools/perf/builtin.h
index c7798c7..11ed837 100644
--- a/tools/perf/builtin.h
+++ b/tools/perf/builtin.h
@@ -35,5 +35,6 @@ extern int cmd_lock(int argc, const char **argv, const char *prefix);
 extern int cmd_kvm(int argc, const char **argv, const char *prefix);
 extern int cmd_test(int argc, const char **argv, const char *prefix);
 extern int cmd_inject(int argc, const char **argv, const char *prefix);
+extern int cmd_bts(int argc, const char **argv, const char *prefix);
 
 #endif
diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt
index 16b5088..956acea 100644
--- a/tools/perf/command-list.txt
+++ b/tools/perf/command-list.txt
@@ -22,3 +22,4 @@ perf-kmem			mainporcelain common
 perf-lock			mainporcelain common
 perf-kvm			mainporcelain common
 perf-test			mainporcelain common
+perf-bts			mainporcelain common
diff --git a/tools/perf/perf.c b/tools/perf/perf.c
index 595d0f4..4f4a98a 100644
--- a/tools/perf/perf.c
+++ b/tools/perf/perf.c
@@ -331,6 +331,7 @@ static void handle_internal_command(int argc, const char **argv)
 		{ "kvm",	cmd_kvm,	0 },
 		{ "test",	cmd_test,	0 },
 		{ "inject",	cmd_inject,	0 },
+		{ "bts",	cmd_bts,	0 },
 	};
 	unsigned int i;
 	static const char ext[] = STRIP_EXTENSION;