From: Greg KH <greg@kroah.com>
To: torvalds@transmeta.com
Cc: linux-usb-devel@lists.sourceforge.net
Subject: [PATCH 04 of 11] USB hpusbscsi driver update

Hi,

Here's a patch against 2.5.3-pre1 for the USB hpusbscsi driver that
removes some dead code, and tries to shave off some cycles in the
interrupt handler.  This patch was written by Oliver Neukum.

thanks,

greg k-h


diff -Nru a/drivers/usb/hpusbscsi.c b/drivers/usb/hpusbscsi.c
--- a/drivers/usb/hpusbscsi.c	Wed Jan 16 09:57:46 2002
+++ b/drivers/usb/hpusbscsi.c	Wed Jan 16 09:57:46 2002
@@ -272,7 +272,7 @@
 	if (!srb->bufflen) {
 		usb_callback = simple_command_callback;
 	} else {
-        	if (srb->use_sg) {
+        	if (likely(srb->use_sg)) {
 			usb_callback = scatter_gather_callback;
 			hpusbscsi->fragment = 0;
 		} else {
@@ -288,10 +288,6 @@
 
 
 	TRACE_STATE;
-	if (hpusbscsi->state != HP_STATE_FREE) {
-		printk(KERN_CRIT"hpusbscsi - Ouch: queueing violation!\n");
-		return 1; /* This must not happen */
-	}
 
         /* We zero the sense buffer to avoid confusing user space */
         memset(srb->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
@@ -313,10 +309,10 @@
 	hpusbscsi->srb = srb;
 
 	res = usb_submit_urb(&hpusbscsi->dataurb);
-	if (res) {
+	if (unlikely(res)) {
 		hpusbscsi->state = HP_STATE_FREE;
 		TRACE_STATE;
-		if (callback) {
+		if (likely(callback != NULL)) {
 			srb->result = DID_ERROR;
 			callback(srb);
 		}
@@ -355,7 +351,7 @@
 
 static void handle_usb_error (struct hpusbscsi *hpusbscsi)
 {
-	if (hpusbscsi->scallback != NULL) {
+	if (likely(hpusbscsi->scallback != NULL)) {
 		hpusbscsi->srb->result = DID_ERROR;
 		hpusbscsi->scallback(hpusbscsi->srb);
 	}
@@ -367,8 +363,8 @@
 	struct hpusbscsi * hpusbscsi = (struct hpusbscsi *)u->context;
 
 DEBUG("Getting status byte %d \n",hpusbscsi->scsi_state_byte);
-	if(u->status < 0) {
-                if (hpusbscsi->state != HP_STATE_FREE)
+	if(unlikely(u->status < 0)) {
+                if (likely(hpusbscsi->state != HP_STATE_FREE))
                         handle_usb_error(hpusbscsi);
 		return;
 	}
@@ -402,7 +398,7 @@
 static void simple_command_callback(struct urb *u)
 {
 	struct hpusbscsi * hpusbscsi = (struct hpusbscsi *)u->context;
-	if (u->status<0) {
+	if (unlikely(u->status<0)) {
 		handle_usb_error(hpusbscsi);
 		return;
         }
@@ -411,7 +407,7 @@
 	        TRACE_STATE;
 		hpusbscsi->state = HP_STATE_WAIT;
 	} else {
-		if (hpusbscsi->scallback != NULL)
+		if (likely(hpusbscsi->scallback != NULL))
 			hpusbscsi->scallback(hpusbscsi->srb);
 		hpusbscsi->state = HP_STATE_FREE;
 	TRACE_STATE;
@@ -426,7 +422,7 @@
         int res;
 
         DEBUG("Going through scatter/gather\n");
-        if (u->status < 0) {
+        if (unlikely(u->status < 0)) {
                 handle_usb_error(hpusbscsi);
                 return;
         }
@@ -452,7 +448,7 @@
         );
 
         res = usb_submit_urb(u);
-        if (res)
+        if (unlikely(res))
                 hpusbscsi->state = HP_STATE_ERROR;
 	TRACE_STATE;
 }
@@ -461,20 +457,20 @@
 {
 	struct hpusbscsi * hpusbscsi = (struct hpusbscsi *)u->context;
 
-        if (u->status < 0) {
+        if (unlikely(u->status < 0)) {
                 handle_usb_error(hpusbscsi);
                 return;
         }
         DEBUG("Data transfer done\n");
 	TRACE_STATE;
 	if (hpusbscsi->state != HP_STATE_PREMATURE) {
-		if (u->status < 0)
+		if (unlikely(u->status < 0))
 			hpusbscsi->state = HP_STATE_ERROR;
 		else
 			hpusbscsi->state = HP_STATE_WAIT;
 		TRACE_STATE;
 	} else {
-		if (hpusbscsi->scallback != NULL)
+		if (likely(hpusbscsi->scallback != NULL))
 			hpusbscsi->scallback(hpusbscsi->srb);
 		hpusbscsi->state = HP_STATE_FREE;
 	}
@@ -485,7 +481,7 @@
 	struct hpusbscsi * hpusbscsi = (struct hpusbscsi *)u->context;
 	int res;
 
-	if (u->status<0) {
+	if (unlikely(u->status<0)) {
                 handle_usb_error(hpusbscsi);
 		return;
         }
@@ -501,7 +497,7 @@
 	);
 
 	res = usb_submit_urb(u);
-	if (res) {
+	if (unlikely(res)) {
                 handle_usb_error(hpusbscsi);
 		return;
         }
@@ -510,10 +506,11 @@
 		hpusbscsi->state = HP_STATE_WORKING;
 	TRACE_STATE;
 	} else {
-		if (hpusbscsi->scallback != NULL)
+		if (likely(hpusbscsi->scallback != NULL))
 			hpusbscsi->scallback(hpusbscsi->srb);
 		hpusbscsi->state = HP_STATE_FREE;
 	TRACE_STATE;
 	}
 }
+