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USB speedtouch: crc optimization

PATCH Applied Duncan Sands 2 participants 2 messages Apr 23, 2003 USB

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Duncan Sands

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#0 lore raw

PATCH 1/1 USB speedtouch: crc optimization

 speedtch.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
drivers/usb/misc/speedtch.c +4 -4
diff -Nru a/drivers/usb/misc/speedtch.c b/drivers/usb/misc/speedtch.c
@@ -406,11 +406,12 @@
 **  encode  **
 *************/
 
+static const unsigned char zeros[ATM_CELL_PAYLOAD];
+
 static void udsl_groom_skb (struct atm_vcc *vcc, struct sk_buff *skb)
 {
 	struct udsl_control *ctrl = UDSL_SKB (skb);
-	unsigned int i, zero_padding;
-	unsigned char zero = 0;
+	unsigned int zero_padding;
 	u32 crc;
 
 	ctrl->atm_data.vcc = vcc;

@@ -436,8 +437,7 @@
 	ctrl->aal5_trailer [3] = skb->len;
 
 	crc = crc32_be (~0, skb->data, skb->len);
-	for (i = 0; i < zero_padding; i++)
-		crc = crc32_be (crc, &zero, 1);
+	crc = crc32_be (crc, zeros, zero_padding);
 	crc = crc32_be (crc, ctrl->aal5_trailer, 4);
 	crc = ~crc;
 

 speedtouch.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
drivers/usb/speedtouch.c +4 -4
diff -Nru a/drivers/usb/speedtouch.c b/drivers/usb/speedtouch.c
@@ -406,11 +406,12 @@
 **  encode  **
 *************/
 
+static const unsigned char zeros[ATM_CELL_PAYLOAD];
+
 static void udsl_groom_skb (struct atm_vcc *vcc, struct sk_buff *skb)
 {
 	struct udsl_control *ctrl = UDSL_SKB (skb);
-	unsigned int i, zero_padding;
-	unsigned char zero = 0;
+	unsigned int zero_padding;
 	u32 crc;
 
 	ctrl->atm_data.vcc = vcc;

@@ -436,8 +437,7 @@
 	ctrl->aal5_trailer [3] = skb->len;
 
 	crc = crc32_be (~0, skb->data, skb->len);
-	for (i = 0; i < zero_padding; i++)
-		crc = crc32_be (crc, &zero, 1);
+	crc = crc32_be (crc, zeros, zero_padding);
 	crc = crc32_be (crc, ctrl->aal5_trailer, 4);
 	crc = ~crc;
 

 speedtch.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
drivers/usb/misc/speedtch.c +4 -4
diff -Nru a/drivers/usb/misc/speedtch.c b/drivers/usb/misc/speedtch.c
@@ -406,11 +406,12 @@
 **  encode  **
 *************/
 
+static const unsigned char zeros[ATM_CELL_PAYLOAD];
+
 static void udsl_groom_skb (struct atm_vcc *vcc, struct sk_buff *skb)
 {
 	struct udsl_control *ctrl = UDSL_SKB (skb);
-	unsigned int i, zero_padding;
-	unsigned char zero = 0;
+	unsigned int zero_padding;
 	u32 crc;
 
 	ctrl->atm_data.vcc = vcc;

@@ -436,8 +437,7 @@
 	ctrl->aal5_trailer [3] = skb->len;
 
 	crc = crc32_be (~0, skb->data, skb->len);
-	for (i = 0; i < zero_padding; i++)
-		crc = crc32_be (crc, &zero, 1);
+	crc = crc32_be (crc, zeros, zero_padding);
 	crc = crc32_be (crc, ctrl->aal5_trailer, 4);
 	crc = ~crc;
Applied
#1 lore raw
Quoted 2 lines · Duncan Sands
 speedtch.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

Applied, thanks.

greg k-h