4.19-stable review patch. If anyone has any objections, please let me know.
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From: Helge Deller deller@gmx.de
[ Upstream commit 52b2d91752a82d9350981eb3b3ffc4b325c84ba9 ]
Do not hardcode processor registers r19 to r22 as scratch registers. Instead let the compiler decide, which may give better optimization results when the functions get inlined.
Signed-off-by: Helge Deller deller@gmx.de Stable-dep-of: a2abae8f0b63 ("parisc: Fix ip_fast_csum") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/parisc/include/asm/checksum.h | 101 +++++++++++++++-------------- 1 file changed, 52 insertions(+), 49 deletions(-)
diff --git a/arch/parisc/include/asm/checksum.h b/arch/parisc/include/asm/checksum.h index 3cbf1f1c1188e..c1c22819a04d1 100644 --- a/arch/parisc/include/asm/checksum.h +++ b/arch/parisc/include/asm/checksum.h @@ -42,31 +42,32 @@ extern __wsum csum_partial_copy_from_user(const void __user *src, static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) { unsigned int sum; + unsigned long t0, t1, t2;
__asm__ __volatile__ ( " ldws,ma 4(%1), %0\n" " addib,<= -4, %2, 2f\n" "\n" -" ldws 4(%1), %%r20\n" -" ldws 8(%1), %%r21\n" -" add %0, %%r20, %0\n" -" ldws,ma 12(%1), %%r19\n" -" addc %0, %%r21, %0\n" -" addc %0, %%r19, %0\n" -"1: ldws,ma 4(%1), %%r19\n" +" ldws 4(%1), %4\n" +" ldws 8(%1), %5\n" +" add %0, %4, %0\n" +" ldws,ma 12(%1), %3\n" +" addc %0, %5, %0\n" +" addc %0, %3, %0\n" +"1: ldws,ma 4(%1), %3\n" " addib,< 0, %2, 1b\n" -" addc %0, %%r19, %0\n" +" addc %0, %3, %0\n" "\n" -" extru %0, 31, 16, %%r20\n" -" extru %0, 15, 16, %%r21\n" -" addc %%r20, %%r21, %0\n" -" extru %0, 15, 16, %%r21\n" -" add %0, %%r21, %0\n" +" extru %0, 31, 16, %4\n" +" extru %0, 15, 16, %5\n" +" addc %4, %5, %0\n" +" extru %0, 15, 16, %5\n" +" add %0, %5, %0\n" " subi -1, %0, %0\n" "2:\n" - : "=r" (sum), "=r" (iph), "=r" (ihl) + : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (t0), "=r" (t1), "=r" (t2) : "1" (iph), "2" (ihl) - : "r19", "r20", "r21", "memory"); + : "memory");
return (__force __sum16)sum; } @@ -126,6 +127,10 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, __u32 len, __u8 proto, __wsum sum) { + unsigned long t0, t1, t2, t3; + + len += proto; /* add 16-bit proto + len */ + __asm__ __volatile__ (
#if BITS_PER_LONG > 32 @@ -136,20 +141,19 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, ** Try to keep 4 registers with "live" values ahead of the ALU. */
-" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */ -" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */ -" add %8, %3, %3\n"/* add 16-bit proto + len */ -" add %%r19, %0, %0\n" -" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */ -" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */ -" add,dc %%r20, %0, %0\n" -" add,dc %%r21, %0, %0\n" -" add,dc %%r22, %0, %0\n" +" ldd,ma 8(%1), %4\n" /* get 1st saddr word */ +" ldd,ma 8(%2), %5\n" /* get 1st daddr word */ +" add %4, %0, %0\n" +" ldd,ma 8(%1), %6\n" /* 2nd saddr */ +" ldd,ma 8(%2), %7\n" /* 2nd daddr */ +" add,dc %5, %0, %0\n" +" add,dc %6, %0, %0\n" +" add,dc %7, %0, %0\n" " add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ -" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */ -" depdi 0, 31, 32, %0\n" /* clear upper half */ -" add %%r19, %0, %0\n" /* fold into 32-bits */ -" addc 0, %0, %0\n" /* add carry */ +" extrd,u %0, 31, 32, %4\n"/* copy upper half down */ +" depdi 0, 31, 32, %0\n"/* clear upper half */ +" add %4, %0, %0\n" /* fold into 32-bits */ +" addc 0, %0, %0\n" /* add carry */
#else
@@ -158,30 +162,29 @@ static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, ** Insn stream is serialized on the carry bit here too. ** result from the previous operation (eg r0 + x) */ - -" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */ -" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */ -" add %8, %3, %3\n" /* add 16-bit proto + len */ -" add %%r19, %0, %0\n" -" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */ -" addc %%r20, %0, %0\n" -" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */ -" addc %%r21, %0, %0\n" -" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */ -" addc %%r22, %0, %0\n" -" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */ -" addc %%r19, %0, %0\n" -" ldw,ma 4(%1), %%r21\n" /* 4th saddr */ -" addc %%r20, %0, %0\n" -" ldw,ma 4(%2), %%r22\n" /* 4th daddr */ -" addc %%r21, %0, %0\n" -" addc %%r22, %0, %0\n" +" ldw,ma 4(%1), %4\n" /* get 1st saddr word */ +" ldw,ma 4(%2), %5\n" /* get 1st daddr word */ +" add %4, %0, %0\n" +" ldw,ma 4(%1), %6\n" /* 2nd saddr */ +" addc %5, %0, %0\n" +" ldw,ma 4(%2), %7\n" /* 2nd daddr */ +" addc %6, %0, %0\n" +" ldw,ma 4(%1), %4\n" /* 3rd saddr */ +" addc %7, %0, %0\n" +" ldw,ma 4(%2), %5\n" /* 3rd daddr */ +" addc %4, %0, %0\n" +" ldw,ma 4(%1), %6\n" /* 4th saddr */ +" addc %5, %0, %0\n" +" ldw,ma 4(%2), %7\n" /* 4th daddr */ +" addc %6, %0, %0\n" +" addc %7, %0, %0\n" " addc %3, %0, %0\n" /* fold in proto+len, catch carry */
#endif - : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len) - : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto) - : "r19", "r20", "r21", "r22", "memory"); + : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len), + "=r" (t0), "=r" (t1), "=r" (t2), "=r" (t3) + : "0" (sum), "1" (saddr), "2" (daddr), "3" (len) + : "memory"); return csum_fold(sum); }