[PATCH v2 1/2] powerpc32: put csum_tcpudp_magic inline

From: Christophe Leroy
Date: Tue Feb 03 2015 - 06:40:27 EST


csum_tcpudp_magic() is only a few instructions, and does not modifies any other
register than the returned result. So it is not worth having it as a separate
function and suffer function branching and saving of volatile registers.
This patch makes it inline by use of the already existing csum_tcpudp_nofold()
function.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>

---
v2: no change

arch/powerpc/include/asm/checksum.h | 15 +++++++++++++++
arch/powerpc/lib/checksum_32.S | 16 ----------------
2 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h
index 8251a3b..cfe806a 100644
--- a/arch/powerpc/include/asm/checksum.h
+++ b/arch/powerpc/include/asm/checksum.h
@@ -19,6 +19,7 @@
#else
extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);

+#ifdef __powerpc64__
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
@@ -27,6 +28,7 @@ extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
unsigned short len,
unsigned short proto,
__wsum sum);
+#endif

/*
* computes the checksum of a memory block at buff, length len,
@@ -127,6 +129,19 @@ static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
#endif
}

+#ifndef __powerpc64__
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+ unsigned short len,
+ unsigned short proto,
+ __wsum sum)
+{
+ return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
+}
+#endif
#endif
#endif /* __KERNEL__ */
#endif
diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
index 7874e8a..6d67e05 100644
--- a/arch/powerpc/lib/checksum_32.S
+++ b/arch/powerpc/lib/checksum_32.S
@@ -41,22 +41,6 @@ _GLOBAL(ip_fast_csum)
blr

/*
- * Compute checksum of TCP or UDP pseudo-header:
- * csum_tcpudp_magic(saddr, daddr, len, proto, sum)
- */
-_GLOBAL(csum_tcpudp_magic)
- rlwimi r5,r6,16,0,15 /* put proto in upper half of len */
- addc r0,r3,r4 /* add 4 32-bit words together */
- adde r0,r0,r5
- adde r0,r0,r7
- addze r0,r0 /* add in final carry */
- rlwinm r3,r0,16,0,31 /* fold two halves together */
- add r3,r0,r3
- not r3,r3
- srwi r3,r3,16
- blr
-
-/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
--
2.1.0

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