perf tools: Use __maybe_used for unused variables

perf defines both __used and __unused variables to use for marking
unused variables. The variable __used is defined to
__attribute__((__unused__)), which contradicts the kernel definition to
__attribute__((__used__)) for new gcc versions. On Android, __used is
also defined in system headers and this leads to warnings like: warning:
'__used__' attribute ignored

__unused is not defined in the kernel and is not a standard definition.
If __unused is included everywhere instead of __used, this leads to
conflicts with glibc headers, since glibc has a variables with this name
in its headers.

The best approach is to use __maybe_unused, the definition used in the
kernel for __attribute__((unused)). In this way there is only one
definition in perf sources (instead of 2 definitions that point to the
same thing: __used and __unused) and it works on both Linux and Android.
This patch simply replaces all instances of __used and __unused with
__maybe_unused.

Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1347315303-29906-7-git-send-email-irina.tirdea@intel.com
[ committer note: fixed up conflict with a116e05 in builtin-sched.c ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/traceevent/event-parse.c

@@ -1824,7 +1824,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
 }
 
 static enum event_type
-process_entry(struct event_format *event __unused, struct print_arg *arg,
+process_entry(struct event_format *event __maybe_unused, struct print_arg *arg,
 	      char **tok)
 {
 	enum event_type type;
@@ -2458,7 +2458,8 @@ process_paren(struct event_format *event, struct print_arg *arg, char **tok)
 
 
 static enum event_type
-process_str(struct event_format *event __unused, struct print_arg *arg, char **tok)
+process_str(struct event_format *event __maybe_unused, struct print_arg *arg,
+	    char **tok)
 {
 	enum event_type type;
 	char *token;
@@ -3653,7 +3654,8 @@ static void free_args(struct print_arg *args)
 }
 
 static char *
-get_bprint_format(void *data, int size __unused, struct event_format *event)
+get_bprint_format(void *data, int size __maybe_unused,
+		  struct event_format *event)
 {
 	struct pevent *pevent = event->pevent;
 	unsigned long long addr;

tools/lib/traceevent/event-parse.h

@@ -24,8 +24,8 @@
 #include <stdarg.h>
 #include <regex.h>
 
-#ifndef __unused
-#define __unused __attribute__ ((unused))
+#ifndef __maybe_unused
+#define __maybe_unused __attribute__((unused))
 #endif
 
 /* ----------------------- trace_seq ----------------------- */

tools/perf/bench/bench.h

@@ -3,7 +3,8 @@
 
 extern int bench_sched_messaging(int argc, const char **argv, const char *prefix);
 extern int bench_sched_pipe(int argc, const char **argv, const char *prefix);
-extern int bench_mem_memcpy(int argc, const char **argv, const char *prefix __used);
+extern int bench_mem_memcpy(int argc, const char **argv,
+			    const char *prefix __maybe_unused);
 extern int bench_mem_memset(int argc, const char **argv, const char *prefix);
 
 #define BENCH_FORMAT_DEFAULT_STR	"default"

tools/perf/bench/mem-memcpy.c

@@ -177,7 +177,7 @@ static double do_memcpy_gettimeofday(memcpy_t fn, size_t len, bool prefault)
 	} while (0)
 
 int bench_mem_memcpy(int argc, const char **argv,
-		     const char *prefix __used)
+		     const char *prefix __maybe_unused)
 {
 	int i;
 	size_t len;

tools/perf/bench/mem-memset.c

@@ -171,7 +171,7 @@ static double do_memset_gettimeofday(memset_t fn, size_t len, bool prefault)
 	} while (0)
 
 int bench_mem_memset(int argc, const char **argv,
-		     const char *prefix __used)
+		     const char *prefix __maybe_unused)
 {
 	int i;
 	size_t len;

tools/perf/bench/sched-messaging.c

@@ -267,7 +267,7 @@ static const char * const bench_sched_message_usage[] = {
 };
 
 int bench_sched_messaging(int argc, const char **argv,
-		    const char *prefix __used)
+		    const char *prefix __maybe_unused)
 {
 	unsigned int i, total_children;
 	struct timeval start, stop, diff;

tools/perf/bench/sched-pipe.c

@@ -43,7 +43,7 @@ static const char * const bench_sched_pipe_usage[] = {
 };
 
 int bench_sched_pipe(int argc, const char **argv,
-		     const char *prefix __used)
+		     const char *prefix __maybe_unused)
 {
 	int pipe_1[2], pipe_2[2];
 	int m = 0, i;
@@ -55,8 +55,8 @@ int bench_sched_pipe(int argc, const char **argv,
 	 * discarding returned value of read(), write()
 	 * causes error in building environment for perf
 	 */
-	int __used ret, wait_stat;
-	pid_t pid, retpid __used;
+	int __maybe_unused ret, wait_stat;
+	pid_t pid, retpid __maybe_unused;
 
 	argc = parse_options(argc, argv, options,
 			     bench_sched_pipe_usage, 0);

tools/perf/builtin-annotate.c

@@ -239,7 +239,7 @@ static const char * const annotate_usage[] = {
 	NULL
 };
 
-int cmd_annotate(int argc, const char **argv, const char *prefix __used)
+int cmd_annotate(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	struct perf_annotate annotate = {
 		.tool = {

tools/perf/builtin-bench.c

@@ -173,7 +173,7 @@ static void all_subsystem(void)
 		all_suite(&subsystems[i]);
 }
 
-int cmd_bench(int argc, const char **argv, const char *prefix __used)
+int cmd_bench(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	int i, j, status = 0;
 

tools/perf/builtin-buildid-cache.c

@@ -51,8 +51,8 @@ static int build_id_cache__add_file(const char *filename, const char *debugdir)
 	return err;
 }
 
-static int build_id_cache__remove_file(const char *filename __used,
-				       const char *debugdir __used)
+static int build_id_cache__remove_file(const char *filename __maybe_unused,
+				       const char *debugdir __maybe_unused)
 {
 	u8 build_id[BUILD_ID_SIZE];
 	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
@@ -120,7 +120,8 @@ static int __cmd_buildid_cache(void)
 	return 0;
 }
 
-int cmd_buildid_cache(int argc, const char **argv, const char *prefix __used)
+int cmd_buildid_cache(int argc, const char **argv,
+		      const char *prefix __maybe_unused)
 {
 	argc = parse_options(argc, argv, buildid_cache_options,
 			     buildid_cache_usage, 0);

tools/perf/builtin-buildid-list.c

@@ -103,7 +103,8 @@ static int __cmd_buildid_list(void)
 	return perf_session__list_build_ids();
 }
 
-int cmd_buildid_list(int argc, const char **argv, const char *prefix __used)
+int cmd_buildid_list(int argc, const char **argv,
+		     const char *prefix __maybe_unused)
 {
 	argc = parse_options(argc, argv, options, buildid_list_usage, 0);
 	setup_pager();

tools/perf/builtin-diff.c

@@ -33,7 +33,7 @@ static int hists__add_entry(struct hists *self,
 	return -ENOMEM;
 }
 
-static int diff__process_sample_event(struct perf_tool *tool __used,
+static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
 				      union perf_event *event,
 				      struct perf_sample *sample,
 				      struct perf_evsel *evsel,
@@ -242,7 +242,7 @@ static const struct option options[] = {
 	OPT_END()
 };
 
-int cmd_diff(int argc, const char **argv, const char *prefix __used)
+int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	sort_order = diff__default_sort_order;
 	argc = parse_options(argc, argv, options, diff_usage, 0);

tools/perf/builtin-evlist.c

@@ -113,7 +113,7 @@ static const char * const evlist_usage[] = {
 	NULL
 };
 
-int cmd_evlist(int argc, const char **argv, const char *prefix __used)
+int cmd_evlist(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	struct perf_attr_details details = { .verbose = false, };
 	const char *input_name = NULL;

tools/perf/builtin-help.c

@@ -426,7 +426,7 @@ static int show_html_page(const char *perf_cmd)
 	return 0;
 }
 
-int cmd_help(int argc, const char **argv, const char *prefix __used)
+int cmd_help(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	const char *alias;
 	int rc = 0;

tools/perf/builtin-inject.c

@@ -17,9 +17,9 @@
 static char		const *input_name = "-";
 static bool		inject_build_ids;
 
-static int perf_event__repipe_synth(struct perf_tool *tool __used,
+static int perf_event__repipe_synth(struct perf_tool *tool __maybe_unused,
 				    union perf_event *event,
-				    struct machine *machine __used)
+				    struct machine *machine __maybe_unused)
 {
 	uint32_t size;
 	void *buf = event;
@@ -40,7 +40,8 @@ static int perf_event__repipe_synth(struct perf_tool *tool __used,
 
 static int perf_event__repipe_op2_synth(struct perf_tool *tool,
 					union perf_event *event,
-					struct perf_session *session __used)
+					struct perf_session *session
+					__maybe_unused)
 {
 	return perf_event__repipe_synth(tool, event, NULL);
 }
@@ -52,13 +53,14 @@ static int perf_event__repipe_event_type_synth(struct perf_tool *tool,
 }
 
 static int perf_event__repipe_tracing_data_synth(union perf_event *event,
-						 struct perf_session *session __used)
+						 struct perf_session *session
+						 __maybe_unused)
 {
 	return perf_event__repipe_synth(NULL, event, NULL);
 }
 
 static int perf_event__repipe_attr(union perf_event *event,
-				   struct perf_evlist **pevlist __used)
+				   struct perf_evlist **pevlist __maybe_unused)
 {
 	int ret;
 	ret = perf_event__process_attr(event, pevlist);
@@ -70,16 +72,16 @@ static int perf_event__repipe_attr(union perf_event *event,
 
 static int perf_event__repipe(struct perf_tool *tool,
 			      union perf_event *event,
-			      struct perf_sample *sample __used,
+			      struct perf_sample *sample __maybe_unused,
 			      struct machine *machine)
 {
 	return perf_event__repipe_synth(tool, event, machine);
 }
 
 static int perf_event__repipe_sample(struct perf_tool *tool,
 				     union perf_event *event,
-			      struct perf_sample *sample __used,
-			      struct perf_evsel *evsel __used,
+			      struct perf_sample *sample __maybe_unused,
+			      struct perf_evsel *evsel __maybe_unused,
 			      struct machine *machine)
 {
 	return perf_event__repipe_synth(tool, event, machine);
@@ -163,7 +165,7 @@ static int dso__inject_build_id(struct dso *self, struct perf_tool *tool,
 static int perf_event__inject_buildid(struct perf_tool *tool,
 				      union perf_event *event,
 				      struct perf_sample *sample,
-				      struct perf_evsel *evsel __used,
+				      struct perf_evsel *evsel __maybe_unused,
 				      struct machine *machine)
 {
 	struct addr_location al;
@@ -224,7 +226,7 @@ struct perf_tool perf_inject = {
 
 extern volatile int session_done;
 
-static void sig_handler(int sig __attribute__((__unused__)))
+static void sig_handler(int sig __maybe_unused)
 {
 	session_done = 1;
 }
@@ -267,7 +269,7 @@ static const struct option options[] = {
 	OPT_END()
 };
 
-int cmd_inject(int argc, const char **argv, const char *prefix __used)
+int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	argc = parse_options(argc, argv, options, report_usage, 0);
 

tools/perf/builtin-kmem.c

@@ -320,7 +320,7 @@ static int perf_evsel__process_kmem_event(struct perf_evsel *evsel,
 	return 0;
 }
 
-static int process_sample_event(struct perf_tool *tool __used,
+static int process_sample_event(struct perf_tool *tool __maybe_unused,
 				union perf_event *event,
 				struct perf_sample *sample,
 				struct perf_evsel *evsel,
@@ -672,8 +672,8 @@ static int setup_sorting(struct list_head *sort_list, const char *arg)
 	return 0;
 }
 
-static int parse_sort_opt(const struct option *opt __used,
-			  const char *arg, int unset __used)
+static int parse_sort_opt(const struct option *opt __maybe_unused,
+			  const char *arg, int unset __maybe_unused)
 {
 	if (!arg)
 		return -1;
@@ -686,22 +686,24 @@ static int parse_sort_opt(const struct option *opt __used,
 	return 0;
 }
 
-static int parse_caller_opt(const struct option *opt __used,
-			  const char *arg __used, int unset __used)
+static int parse_caller_opt(const struct option *opt __maybe_unused,
+			    const char *arg __maybe_unused,
+			    int unset __maybe_unused)
 {
 	caller_flag = (alloc_flag + 1);
 	return 0;
 }
 
-static int parse_alloc_opt(const struct option *opt __used,
-			  const char *arg __used, int unset __used)
+static int parse_alloc_opt(const struct option *opt __maybe_unused,
+			   const char *arg __maybe_unused,
+			   int unset __maybe_unused)
 {
 	alloc_flag = (caller_flag + 1);
 	return 0;
 }
 
-static int parse_line_opt(const struct option *opt __used,
-			  const char *arg, int unset __used)
+static int parse_line_opt(const struct option *opt __maybe_unused,
+			  const char *arg, int unset __maybe_unused)
 {
 	int lines;
 
@@ -771,7 +773,7 @@ static int __cmd_record(int argc, const char **argv)
 	return cmd_record(i, rec_argv, NULL);
 }
 
-int cmd_kmem(int argc, const char **argv, const char *prefix __used)
+int cmd_kmem(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	argc = parse_options(argc, argv, kmem_options, kmem_usage, 0);
 

tools/perf/builtin-kvm.c

@@ -102,7 +102,7 @@ static int __cmd_buildid_list(int argc, const char **argv)
 	return cmd_buildid_list(i, rec_argv, NULL);
 }
 
-int cmd_kvm(int argc, const char **argv, const char *prefix __used)
+int cmd_kvm(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	perf_host  = 0;
 	perf_guest = 1;

tools/perf/builtin-list.c

@@ -14,7 +14,7 @@
 #include "util/parse-events.h"
 #include "util/cache.h"
 
-int cmd_list(int argc, const char **argv, const char *prefix __used)
+int cmd_list(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	setup_pager();
 

tools/perf/builtin-lock.c

@@ -870,7 +870,7 @@ static int dump_info(void)
 	return rc;
 }
 
-static int process_sample_event(struct perf_tool *tool __used,
+static int process_sample_event(struct perf_tool *tool __maybe_unused,
 				union perf_event *event,
 				struct perf_sample *sample,
 				struct perf_evsel *evsel,
@@ -1020,7 +1020,7 @@ static int __cmd_record(int argc, const char **argv)
 	return cmd_record(i, rec_argv, NULL);
 }
 
-int cmd_lock(int argc, const char **argv, const char *prefix __used)
+int cmd_lock(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	unsigned int i;
 	int rc = 0;