[PATCH v3 1/2] powerpc: put csum_tcpudp_magic inline

From: Christophe Leroy
Date: Tue May 19 2015 - 11:21:02 EST


csum_tcpudp_magic() is only a few instructions, and does modify
really few registers. 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>
---
arch/powerpc/include/asm/checksum.h | 21 ++++++++++++---------
arch/powerpc/lib/checksum_32.S | 16 ----------------
arch/powerpc/lib/checksum_64.S | 21 ---------------------
3 files changed, 12 insertions(+), 46 deletions(-)

diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h
index 8251a3b..5e43d2d 100644
--- a/arch/powerpc/include/asm/checksum.h
+++ b/arch/powerpc/include/asm/checksum.h
@@ -20,15 +20,6 @@
extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);

/*
- * computes the checksum of the TCP/UDP pseudo-header
- * returns a 16-bit checksum, already complemented
- */
-extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
- unsigned short len,
- unsigned short proto,
- __wsum sum);
-
-/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
@@ -127,6 +118,18 @@ static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
#endif
}

+/*
+ * 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 /* __KERNEL__ */
#endif
diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
index e23a436..d6fab08 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)
*
diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S
index 57a0720..f3ef354 100644
--- a/arch/powerpc/lib/checksum_64.S
+++ b/arch/powerpc/lib/checksum_64.S
@@ -45,27 +45,6 @@ _GLOBAL(ip_fast_csum)
blr

/*
- * Compute checksum of TCP or UDP pseudo-header:
- * csum_tcpudp_magic(r3=saddr, r4=daddr, r5=len, r6=proto, r7=sum)
- * No real gain trying to do this specially for 64 bit, but
- * the 32 bit addition may spill into the upper bits of
- * the doubleword so we still must fold it down from 64.
- */
-_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
- rldicl r4,r0,32,0 /* fold 64 bit value */
- add r0,r4,r0
- srdi r0,r0,32
- 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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