[PATCH v4 23/40] usb: cdc-acm: optimize acm_softint()

[Yury Norov]

acm_softint() uses for-loop to traverse urbs_in_error_delay bitmap
bit by bit to find and clear set bits.

Simplify it by using for_each_test_and_clear_bit(), because it doesn't
test already clear bits.

Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx>
Acked-by: Oliver Neukum <oneukum@xxxxxxxx>
---
 drivers/usb/class/cdc-acm.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 0e7439dba8fe..f8940f0d7ad8 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -18,6 +18,7 @@
 #undef DEBUG
 #undef VERBOSE_DEBUG
 
+#include <linux/find_atomic.h>
 #include <linux/kernel.h>
 #include <linux/sched/signal.h>
 #include <linux/errno.h>
@@ -613,9 +614,8 @@ static void acm_softint(struct work_struct *work)
 	}
 
 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
-		for (i = 0; i < acm->rx_buflimit; i++)
-			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
-				acm_submit_read_urb(acm, i, GFP_KERNEL);
+		for_each_test_and_clear_bit(i, &acm->urbs_in_error_delay, acm->rx_buflimit)
+			acm_submit_read_urb(acm, i, GFP_KERNEL);
 	}
 
 	if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags))
-- 
2.43.0