[PATCH] snd_usb_caiaq: use likely()/unlikely()

[Daniel Mack <daniel@caiaq.org>]

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Use likely() and unlikely() in code which is called regularily.

Signed-off-by: Daniel Mack <daniel@caiaq.de>


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diff --git a/sound/usb/caiaq/caiaq-audio.c b/sound/usb/caiaq/caiaq-audio.c
index 24970a5..8cb417f 100644
--- a/sound/usb/caiaq/caiaq-audio.c
+++ b/sound/usb/caiaq/caiaq-audio.c
@@ -365,10 +365,10 @@ static void read_in_urb_mode2(struct snd_usb_caiaqdev *dev,
 
 				check_byte = MAKE_CHECKBYTE(dev, stream, i);
 				
-				if ((usb_buf[i] & 0x3f) != check_byte)
+				if (unlikely((usb_buf[i] & 0x3f) != check_byte))
 					dev->input_panic = 1;
 
-				if (usb_buf[i] & 0x80)
+				if (unlikely(usb_buf[i] & 0x80))
 					dev->output_panic = 1;
 			}
 		}
@@ -394,7 +394,7 @@ static void read_in_urb(struct snd_usb_caiaqdev *dev,
 			const struct urb *urb,
 			const struct usb_iso_packet_descriptor *iso)
 {
-	if (!dev->streaming)
+	if (unlikely(!dev->streaming))
 		return;
 
 	switch (dev->spec.data_alignment) {
@@ -406,7 +406,7 @@ static void read_in_urb(struct snd_usb_caiaqdev *dev,
 		break;
 	}
 
-	if (dev->input_panic || dev->output_panic) {
+	if (unlikely(dev->input_panic || dev->output_panic)) {
 		debug("streaming error detected %s %s\n", 
 				dev->input_panic ? "(input)" : "",
 				dev->output_panic ? "(output)" : "");
@@ -454,12 +454,12 @@ static void read_completed(struct urb *urb)
 	struct urb *out;
 	int frame, len, send_it = 0, outframe = 0;
 
-	if (urb->status || !info)
+	if (unlikely(urb->status || !info))
 		return;
 
 	dev = info->dev;
 
-	if (!dev->streaming)
+	if (unlikely(!dev->streaming))
 		return;
 
 	out = dev->data_urbs_out[info->index];
@@ -467,7 +467,7 @@ static void read_completed(struct urb *urb)
 	/* read the recently received packet and send back one which has
 	 * the same layout */
 	for (frame = 0; frame < FRAMES_PER_URB; frame++) {
-		if (urb->iso_frame_desc[frame].status)
+		if (unlikely(urb->iso_frame_desc[frame].status != 0))
 			continue;
 
 		len = urb->iso_frame_desc[outframe].actual_length;
@@ -488,7 +488,7 @@ static void read_completed(struct urb *urb)
 		outframe++;
 	}
 
-	if (send_it) {
+	if (likely(send_it)) {
 		out->number_of_packets = FRAMES_PER_URB;
 		out->transfer_flags = URB_ISO_ASAP;
 		usb_submit_urb(out, GFP_ATOMIC);
@@ -511,7 +511,7 @@ static void write_completed(struct urb *urb)
 	struct snd_usb_caiaq_cb_info *info = urb->context;
 	struct snd_usb_caiaqdev *dev = info->dev;
 
-	if (!dev->output_running) {
+	if (unlikely(!dev->output_running)) {
 		dev->output_running = 1;
 		wake_up(&dev->prepare_wait_queue);
 	}
diff --git a/sound/usb/caiaq/caiaq-device.c b/sound/usb/caiaq/caiaq-device.c
index e97d8b2..e1dbce5 100644
--- a/sound/usb/caiaq/caiaq-device.c
+++ b/sound/usb/caiaq/caiaq-device.c
@@ -42,7 +42,7 @@
 #endif
 
 MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>");
-MODULE_DESCRIPTION("caiaq USB audio, version 1.3.6");
+MODULE_DESCRIPTION("caiaq USB audio, version 1.3.7");
 MODULE_LICENSE("GPL");
 MODULE_SUPPORTED_DEVICE("{{Native Instruments, RigKontrol2},"
 			 "{Native Instruments, RigKontrol3},"
@@ -119,7 +119,7 @@ static void usb_ep1_command_reply_dispatch (struct urb* urb)
 	struct snd_usb_caiaqdev *dev = urb->context;
 	unsigned char *buf = urb->transfer_buffer;
 
-	if (urb->status || !dev) {
+	if (unlikely(urb->status || !dev)) {
 		log("received EP1 urb->status = %i\n", urb->status);
 		return;
 	}

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