From: Heiko Carstens <hca@linux.ibm.com>
Date: Fri, 15 Jan 2021 19:01:36 +0000 (+0100)
Subject: s390/bitops: remove small optimization to fix clang build
X-Git-Tag: v5.15~1740^2~63
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=efe5e0fea4b24872736c62a0bcfc3f99bebd2005;p=platform%2Fkernel%2Flinux-starfive.git

s390/bitops: remove small optimization to fix clang build

clang does not know about the 'b1' construct used in bitops inline
assembly. Since the plan is to use compiler atomic builtins anyway
there is no point in requesting clang support for this. Especially if
one considers that the kernel seems to be the only user of this.

With removing this small optimization it is possible to compile the
kernel also with -march=zEC12 and higher using clang.

Build error:

In file included from ./include/linux/bitops.h:32:
./arch/s390/include/asm/bitops.h:69:4: error: invalid operand in inline asm: 'oi        $0,${1:b}'
                        "oi     %0,%b1\n"
                        ^

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---

diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h
index 431e208..31121d3 100644
--- a/arch/s390/include/asm/bitops.h
+++ b/arch/s390/include/asm/bitops.h
@@ -61,18 +61,6 @@ static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned lon
 	unsigned long *addr = __bitops_word(nr, ptr);
 	unsigned long mask;
 
-#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
-	if (__builtin_constant_p(nr)) {
-		unsigned char *caddr = __bitops_byte(nr, ptr);
-
-		asm volatile(
-			"oi	%0,%b1\n"
-			: "+Q" (*caddr)
-			: "i" (1 << (nr & 7))
-			: "cc", "memory");
-		return;
-	}
-#endif
 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
 	__atomic64_or(mask, (long *)addr);
 }
@@ -82,18 +70,6 @@ static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned l
 	unsigned long *addr = __bitops_word(nr, ptr);
 	unsigned long mask;
 
-#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
-	if (__builtin_constant_p(nr)) {
-		unsigned char *caddr = __bitops_byte(nr, ptr);
-
-		asm volatile(
-			"ni	%0,%b1\n"
-			: "+Q" (*caddr)
-			: "i" (~(1 << (nr & 7)))
-			: "cc", "memory");
-		return;
-	}
-#endif
 	mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
 	__atomic64_and(mask, (long *)addr);
 }
@@ -104,18 +80,6 @@ static __always_inline void arch_change_bit(unsigned long nr,
 	unsigned long *addr = __bitops_word(nr, ptr);
 	unsigned long mask;
 
-#ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
-	if (__builtin_constant_p(nr)) {
-		unsigned char *caddr = __bitops_byte(nr, ptr);
-
-		asm volatile(
-			"xi	%0,%b1\n"
-			: "+Q" (*caddr)
-			: "i" (1 << (nr & 7))
-			: "cc", "memory");
-		return;
-	}
-#endif
 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
 	__atomic64_xor(mask, (long *)addr);
 }