s390/bitops: make bitops only work on longs

The bitops code was optimized to generate test under mask instructions
with the __bitops_byte() helper. However that was many years ago and
in the meantime a lot of new instructions were introduced.

Changing the code so that it always operates on longs nowadays even
generates shorter code (~ -20kb, defconfig, gcc 10, march=zE12).

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

diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h
index 31121d32f81d457ccd46284c76ebba11e69a8fbf..68da67d2c4c97ee3addfb539afdca9f94ba50608 100644 (file)
--- a/arch/s390/include/asm/bitops.h
+++ b/arch/s390/include/asm/bitops.h
@@ -42,7 +42,7 @@
 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
 
 static inline unsigned long *
-__bitops_word(unsigned long nr, volatile unsigned long *ptr)
+__bitops_word(unsigned long nr, const volatile unsigned long *ptr)
 {
        unsigned long addr;
 
@@ -50,37 +50,33 @@ __bitops_word(unsigned long nr, volatile unsigned long *ptr)
        return (unsigned long *)addr;
 }
 
-static inline unsigned char *
-__bitops_byte(unsigned long nr, volatile unsigned long *ptr)
+static inline unsigned long __bitops_mask(unsigned long nr)
 {
-       return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
+       return 1UL << (nr & (BITS_PER_LONG - 1));
 }
 
 static __always_inline void arch_set_bit(unsigned long nr, volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long mask;
+       unsigned long mask = __bitops_mask(nr);
 
-       mask = 1UL << (nr & (BITS_PER_LONG - 1));
        __atomic64_or(mask, (long *)addr);
 }
 
 static __always_inline void arch_clear_bit(unsigned long nr, volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long mask;
+       unsigned long mask = __bitops_mask(nr);
 
-       mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
-       __atomic64_and(mask, (long *)addr);
+       __atomic64_and(~mask, (long *)addr);
 }
 
 static __always_inline void arch_change_bit(unsigned long nr,
                                            volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long mask;
+       unsigned long mask = __bitops_mask(nr);
 
-       mask = 1UL << (nr & (BITS_PER_LONG - 1));
        __atomic64_xor(mask, (long *)addr);
 }
 
@@ -88,99 +84,104 @@ static inline bool arch_test_and_set_bit(unsigned long nr,
                                         volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long old, mask;
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       mask = 1UL << (nr & (BITS_PER_LONG - 1));
        old = __atomic64_or_barrier(mask, (long *)addr);
-       return (old & mask) != 0;
+       return old & mask;
 }
 
 static inline bool arch_test_and_clear_bit(unsigned long nr,
                                           volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long old, mask;
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
-       old = __atomic64_and_barrier(mask, (long *)addr);
-       return (old & ~mask) != 0;
+       old = __atomic64_and_barrier(~mask, (long *)addr);
+       return old & mask;
 }
 
 static inline bool arch_test_and_change_bit(unsigned long nr,
                                            volatile unsigned long *ptr)
 {
        unsigned long *addr = __bitops_word(nr, ptr);
-       unsigned long old, mask;
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       mask = 1UL << (nr & (BITS_PER_LONG - 1));
        old = __atomic64_xor_barrier(mask, (long *)addr);
-       return (old & mask) != 0;
+       return old & mask;
 }
 
 static inline void arch___set_bit(unsigned long nr, volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
 
-       *addr |= 1 << (nr & 7);
+       *addr |= mask;
 }
 
 static inline void arch___clear_bit(unsigned long nr,
                                    volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
 
-       *addr &= ~(1 << (nr & 7));
+       *addr &= ~mask;
 }
 
 static inline void arch___change_bit(unsigned long nr,
                                     volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
 
-       *addr ^= 1 << (nr & 7);
+       *addr ^= mask;
 }
 
 static inline bool arch___test_and_set_bit(unsigned long nr,
                                           volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
-       unsigned char ch;
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       ch = *addr;
-       *addr |= 1 << (nr & 7);
-       return (ch >> (nr & 7)) & 1;
+       old = *addr;
+       *addr |= mask;
+       return old & mask;
 }
 
 static inline bool arch___test_and_clear_bit(unsigned long nr,
                                             volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
-       unsigned char ch;
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       ch = *addr;
-       *addr &= ~(1 << (nr & 7));
-       return (ch >> (nr & 7)) & 1;
+       old = *addr;
+       *addr &= ~mask;
+       return old & mask;
 }
 
 static inline bool arch___test_and_change_bit(unsigned long nr,
                                              volatile unsigned long *ptr)
 {
-       unsigned char *addr = __bitops_byte(nr, ptr);
-       unsigned char ch;
+       unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
+       unsigned long old;
 
-       ch = *addr;
-       *addr ^= 1 << (nr & 7);
-       return (ch >> (nr & 7)) & 1;
+       old = *addr;
+       *addr ^= mask;
+       return old & mask;
 }
 
 static inline bool arch_test_bit(unsigned long nr,
                                 const volatile unsigned long *ptr)
 {
-       const volatile unsigned char *addr;
+       const volatile unsigned long *addr = __bitops_word(nr, ptr);
+       unsigned long mask = __bitops_mask(nr);
 
-       addr = ((const volatile unsigned char *)ptr);
-       addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
-       return (*addr >> (nr & 7)) & 1;
+       return *addr & mask;
 }
 
 static inline bool arch_test_and_set_bit_lock(unsigned long nr,