bthread: remove thread exit codes

Follow-up commit will replace blocking bthread_stop with non-blocking
bthread_cancel. Prepare for this by dropping exit codes. This is not
much of a loss, because most users of bthreads will only call
bthread_stop at cleanup time. bthread command is an exception, so have
it take manual care of passing around exit codes.

As we touch the bthread_stop prototype anyway, rename it to
__bthread_stop. This will make it clearer in the future, that it's not
meant for driver use.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20210628070732.16812-1-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 30 insertions, 18 deletions

diff --git a/commands/bthread.c b/commands/bthread.c
index 0c9c221884..446fe9c37a 100644
--- a/commands/bthread.c
+++ b/commands/bthread.c
@@ -33,12 +33,10 @@ static int bthread_time(void)
 	return i;
 }
 
-static int bthread_infinite(void *data)
+static void bthread_infinite(void *data)
 {
 	while (!bthread_should_stop())
 		;
-
-	return 0;
 }
 
 static int bthread_isolated_time(void)
@@ -62,14 +60,20 @@ static int bthread_isolated_time(void)
 		i += 2;
 	}
 
-	bthread_stop(bthread);
+	__bthread_stop(bthread);
 	bthread_free(bthread);
 
 	return i;
 }
 
-static int bthread_printer(void *arg)
+struct arg {
+	unsigned long in;
+	long out;
+};
+
+static void bthread_printer(void *_arg)
 {
+	struct arg *arg = _arg;
 	volatile u64 start;
 	volatile unsigned long i = 0;
 	start = get_time_ns();
@@ -78,28 +82,30 @@ static int bthread_printer(void *arg)
 		if (!is_timeout_non_interruptible(start, 225 * MSECOND))
 			continue;
 
-		if ((unsigned long)arg == i++)
+		if (arg->in == i++)
 			printf("%s yield #%lu\n", bthread_name(current), i);
 		start = get_time_ns();
 	}
 
-	return i;
+	arg->out = i;
 }
 
 static int yields;
 
-static int bthread_spawner(void *arg)
+static void bthread_spawner(void *_spawner_arg)
 {
+	struct arg *arg, *spawner_arg = _spawner_arg;
 	struct bthread *bthread[4];
 	volatile u64 start;
 	volatile unsigned long i = 0;
 	int ret = 0;
-	int ecode;
 
 	start = get_time_ns();
 
 	for (i = 0; i < ARRAY_SIZE(bthread); i++) {
-		bthread[i] = bthread_run(bthread_printer, (void *)(long)i,
+		arg = malloc(sizeof(*arg));
+		arg->in = i;
+		bthread[i] = bthread_run(bthread_printer, arg,
 					 "%s-bthread%u", bthread_name(current), i+1);
 		if (!bthread[i]) {
 			ret = -ENOMEM;
@@ -112,14 +118,16 @@ static int bthread_spawner(void *arg)
 
 cleanup:
 	while (i--) {
-		ecode = bthread_stop(bthread[i]);
+		arg = bthread_data(bthread[i]);
+		__bthread_stop(bthread[i]);
 		bthread_free(bthread[i]);
 
-		if (!ret && (ecode != 4 || yields < ecode))
+		if (!ret && (arg->out != 4 || yields < arg->out))
 			ret = -EIO;
+		free(arg);
 	}
 
-	return ret;
+	spawner_arg->out = ret;
 }
 
 struct spawn {
@@ -132,8 +140,9 @@ static int do_bthread(int argc, char *argv[])
 	LIST_HEAD(spawners);
 	struct spawn *spawner, *tmp;
 	int ret = 0;
-	int ecode, opt, i = 0;
+	int opt, i = 0;
 	bool time = false;
+	struct arg *arg;
 
 	while ((opt = getopt(argc, argv, "itcv")) > 0) {
 		switch (opt) {
@@ -146,7 +155,8 @@ static int do_bthread(int argc, char *argv[])
 			break;
 		case 'v':
 			spawner = xzalloc(sizeof(*spawner));
-			spawner->bthread = bthread_run(bthread_spawner, NULL,
+			arg = malloc(sizeof(*arg));
+			spawner->bthread = bthread_run(bthread_spawner, arg,
 						       "spawner%u", ++i);
 			if (!spawner->bthread) {
 				free(spawner);
@@ -172,10 +182,12 @@ static int do_bthread(int argc, char *argv[])
 
 cleanup:
 	list_for_each_entry_safe(spawner, tmp, &spawners, list) {
-		ecode = bthread_stop(spawner->bthread);
+		arg = bthread_data(spawner->bthread);
+		__bthread_stop(spawner->bthread);
 		bthread_free(spawner->bthread);
-		if (!ret && ecode)
-			ret = ecode;
+		if (!ret && arg->out)
+			ret = arg->out;
+		free(arg);
 		free(spawner);
 	}