Commit 20c1f641 authored Jun 23, 2009 by Arnd Bergmann

lib/checksum.c: make do_csum optional



Mike Frysinger suggested that do_csum should be optional
so that an architecture can use the generic checksum code
but still provide an optimized fast-path for the most
critical function.

This can mean an implementation using inline assembly,
or in case of Alpha one using 64-bit arithmetic in C.

Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

parent c44ba9f6

lib/checksum.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@

		#include <asm/byteorder.h>

		#ifndef do_csum
		static inline unsigned short from32to16(unsigned int x)
		{
		/* add up 16-bit and 16-bit for 16+c bit */
		@@ -102,6 +103,7 @@ static unsigned int do_csum(const unsigned char *buff, int len)
		out:
		return result;
		}
		#endif

		/*
		* This is a version of ip_compute_csum() optimized for IP headers,