perf report: Relax -g option parsing not to limit the option order

Current perf report -g/--call-graph option parser requires for option
argument having following order:

  type,min_percent[,print_limit],order,key

But sometimes it's annoying to type all even if one just wants to change
the "order" or "key" setting.

This patch fixes it to remove the ordering restriction so that one can
use just "-g caller", for instance.  The only remaining restriction is
that the "print_limit" always comes after the "min_percent".

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rodrigo Campos <rodrigo@sdfg.com.ar>
Link: http://lkml.kernel.org/r/1407996100-6359-2-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/callchain.c

@@ -28,74 +28,55 @@ __thread struct callchain_cursor callchain_cursor;
 int
 parse_callchain_report_opt(const char *arg)
 {
-	char *tok, *tok2;
+	char *tok;
 	char *endptr;
+	bool minpcnt_set = false;
 
 	symbol_conf.use_callchain = true;
 
 	if (!arg)
 		return 0;
 
-	tok = strtok((char *)arg, ",");
-	if (!tok)
-		return -1;
+	while ((tok = strtok((char *)arg, ",")) != NULL) {
+		if (!strncmp(tok, "none", strlen(tok))) {
+			callchain_param.mode = CHAIN_NONE;
+			symbol_conf.use_callchain = false;
+			return 0;
+		}
 
-	/* get the output mode */
-	if (!strncmp(tok, "graph", strlen(arg))) {
-		callchain_param.mode = CHAIN_GRAPH_ABS;
+		/* try to get the output mode */
+		if (!strncmp(tok, "graph", strlen(tok)))
+			callchain_param.mode = CHAIN_GRAPH_ABS;
+		else if (!strncmp(tok, "flat", strlen(tok)))
+			callchain_param.mode = CHAIN_FLAT;
+		else if (!strncmp(tok, "fractal", strlen(tok)))
+			callchain_param.mode = CHAIN_GRAPH_REL;
+		/* try to get the call chain order */
+		else if (!strncmp(tok, "caller", strlen(tok)))
+			callchain_param.order = ORDER_CALLER;
+		else if (!strncmp(tok, "callee", strlen(tok)))
+			callchain_param.order = ORDER_CALLEE;
+		/* try to get the sort key */
+		else if (!strncmp(tok, "function", strlen(tok)))
+			callchain_param.key = CCKEY_FUNCTION;
+		else if (!strncmp(tok, "address", strlen(tok)))
+			callchain_param.key = CCKEY_ADDRESS;
+		/* try to get the min percent */
+		else if (!minpcnt_set) {
+			callchain_param.min_percent = strtod(tok, &endptr);
+			if (tok == endptr)
+				return -1;
+			minpcnt_set = true;
+		} else {
+			/* try print limit at last */
+			callchain_param.print_limit = strtoul(tok, &endptr, 0);
+			if (tok == endptr)
+				return -1;
+		}
 
-	} else if (!strncmp(tok, "flat", strlen(arg))) {
-		callchain_param.mode = CHAIN_FLAT;
-	} else if (!strncmp(tok, "fractal", strlen(arg))) {
-		callchain_param.mode = CHAIN_GRAPH_REL;
-	} else if (!strncmp(tok, "none", strlen(arg))) {
-		callchain_param.mode = CHAIN_NONE;
-		symbol_conf.use_callchain = false;
-		return 0;
-	} else {
-		return -1;
+		arg = NULL;
 	}
 
-	/* get the min percentage */
-	tok = strtok(NULL, ",");
-	if (!tok)
-		goto setup;
-
-	callchain_param.min_percent = strtod(tok, &endptr);
-	if (tok == endptr)
-		return -1;
-
-	/* get the print limit */
-	tok2 = strtok(NULL, ",");
-	if (!tok2)
-		goto setup;
-
-	if (tok2[0] != 'c') {
-		callchain_param.print_limit = strtoul(tok2, &endptr, 0);
-		tok2 = strtok(NULL, ",");
-		if (!tok2)
-			goto setup;
-	}
-
-	/* get the call chain order */
-	if (!strncmp(tok2, "caller", strlen("caller")))
-		callchain_param.order = ORDER_CALLER;
-	else if (!strncmp(tok2, "callee", strlen("callee")))
-		callchain_param.order = ORDER_CALLEE;
-	else
-		return -1;
-
-	/* Get the sort key */
-	tok2 = strtok(NULL, ",");
-	if (!tok2)
-		goto setup;
-	if (!strncmp(tok2, "function", strlen("function")))
-		callchain_param.key = CCKEY_FUNCTION;
-	else if (!strncmp(tok2, "address", strlen("address")))
-		callchain_param.key = CCKEY_ADDRESS;
-	else
-		return -1;
-setup:
 	if (callchain_register_param(&callchain_param) < 0) {
 		pr_err("Can't register callchain params\n");
 		return -1;