perf trace: Add alignment spaces after the closing parens

To use strace's style, helping in comparing the output of 'perf trace'
with the one from 'strace', to help in upcoming regression tests.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-mw6peotz4n84rga0fk78buff@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-trace.c

@@ -1741,7 +1741,7 @@ static int trace__printf_interrupted_entry(struct trace *trace)
 		return 0;
 
 	printed  = trace__fprintf_entry_head(trace, trace->current, 0, false, ttrace->entry_time, trace->output);
-	printed += fprintf(trace->output, "%-*s) ...\n", trace->args_alignment, ttrace->entry_str);
+	printed += fprintf(trace->output, ")%-*s ...\n", trace->args_alignment, ttrace->entry_str);
 	ttrace->entry_pending = false;
 
 	++trace->nr_events_printed;
@@ -1798,7 +1798,7 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
 {
 	char *msg;
 	void *args;
-	size_t printed = 0;
+	int printed = 0;
 	struct thread *thread;
 	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1;
 	int augmented_args_size = 0;
@@ -1847,8 +1847,13 @@ static int trace__sys_enter(struct trace *trace, struct perf_evsel *evsel,
 
 	if (sc->is_exit) {
 		if (!(trace->duration_filter || trace->summary_only || trace->failure_only || trace->min_stack)) {
+			int alignment = 0;
+
 			trace__fprintf_entry_head(trace, thread, 0, false, ttrace->entry_time, trace->output);
-			fprintf(trace->output, "%-*s)\n", trace->args_alignment, ttrace->entry_str);
+			printed = fprintf(trace->output, "%s)", ttrace->entry_str);
+			if (trace->args_alignment > printed)
+				alignment = trace->args_alignment - printed;
+			fprintf(trace->output, "%*s= ?\n", alignment, " ");
 		}
 	} else {
 		ttrace->entry_pending = true;
@@ -1943,7 +1948,8 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
 	u64 duration = 0;
 	bool duration_calculated = false;
 	struct thread *thread;
-	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1, callchain_ret = 0;
+	int id = perf_evsel__sc_tp_uint(evsel, id, sample), err = -1, callchain_ret = 0, printed = 0;
+	int alignment = trace->args_alignment;
 	struct syscall *sc = trace__syscall_info(trace, evsel, id);
 	struct thread_trace *ttrace;
 
@@ -1991,28 +1997,37 @@ static int trace__sys_exit(struct trace *trace, struct perf_evsel *evsel,
 	trace__fprintf_entry_head(trace, thread, duration, duration_calculated, ttrace->entry_time, trace->output);
 
 	if (ttrace->entry_pending) {
-		fprintf(trace->output, "%-*s", trace->args_alignment, ttrace->entry_str);
+		printed = fprintf(trace->output, "%s", ttrace->entry_str);
 	} else {
 		fprintf(trace->output, " ... [");
 		color_fprintf(trace->output, PERF_COLOR_YELLOW, "continued");
 		fprintf(trace->output, "]: %s()", sc->name);
 	}
 
+	printed++; /* the closing ')' */
+
+	if (alignment > printed)
+		alignment -= printed;
+	else
+		alignment = 0;
+
+	fprintf(trace->output, ")%*s= ", alignment, " ");
+
 	if (sc->fmt == NULL) {
 		if (ret < 0)
 			goto errno_print;
 signed_print:
-		fprintf(trace->output, ") = %ld", ret);
+		fprintf(trace->output, "%ld", ret);
 	} else if (ret < 0) {
 errno_print: {
 		char bf[STRERR_BUFSIZE];
 		const char *emsg = str_error_r(-ret, bf, sizeof(bf)),
 			   *e = errno_to_name(evsel, -ret);
 
-		fprintf(trace->output, ") = -1 %s %s", e, emsg);
+		fprintf(trace->output, "-1 %s %s", e, emsg);
 	}
 	} else if (ret == 0 && sc->fmt->timeout)
-		fprintf(trace->output, ") = 0 Timeout");
+		fprintf(trace->output, "0 Timeout");
 	else if (ttrace->ret_scnprintf) {
 		char bf[1024];
 		struct syscall_arg arg = {
@@ -2022,14 +2037,14 @@ errno_print: {
 		};
 		ttrace->ret_scnprintf(bf, sizeof(bf), &arg);
 		ttrace->ret_scnprintf = NULL;
-		fprintf(trace->output, ") = %s", bf);
+		fprintf(trace->output, "%s", bf);
 	} else if (sc->fmt->hexret)
-		fprintf(trace->output, ") = %#lx", ret);
+		fprintf(trace->output, "%#lx", ret);
 	else if (sc->fmt->errpid) {
 		struct thread *child = machine__find_thread(trace->host, ret, ret);
 
 		if (child != NULL) {
-			fprintf(trace->output, ") = %ld", ret);
+			fprintf(trace->output, "%ld", ret);
 			if (child->comm_set)
 				fprintf(trace->output, " (%s)", thread__comm_str(child));
 			thread__put(child);