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locking/atomic/x86: Un-macro-ify atomic ops implementation

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CPP turns perfectly readable code into a much harder to read syntactic soup.

Ingo suggested to write them out as-is in C and ignore the higher linecount.

Do this.

(As a side effect, plain C functions will be easier to KASAN-instrument as well.)

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kasan-dev@googlegroups.com
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/a35b983dd3be937a3cf63c4e2db487de2cdc7b8f.1497690003.git.dvyukov@google.com
[ Beautified the C code some more and twiddled the changelog
  to mention the linecount increase and the KASAN benefit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Dmitry Vyukov
2017-06-17 11:15:27 +02:00
committed by Ingo Molnar
parent fd25d19f6b
commit ba1c9f83f6
3 changed files with 149 additions and 72 deletions
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67
arch/x86/include/asm/atomic64_64.h
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@@ -226,34 +226,55 @@ static inline long atomic64_dec_if_positive(atomic64_t *v)
return dec;
}
#define ATOMIC64_OP(op) \
static inline void atomic64_##op(long i, atomic64_t *v) \
{ \
asm volatile(LOCK_PREFIX #op"q %1,%0" \
: "+m" (v->counter) \
: "er" (i) \
: "memory"); \
static inline void atomic64_and(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "andq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
#define ATOMIC64_FETCH_OP(op, c_op) \
static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
{ \
long val = atomic64_read(v); \
do { \
} while (!atomic64_try_cmpxchg(v, &val, val c_op i)); \
return val; \
static inline long atomic64_fetch_and(long i, atomic64_t *v)
{
long val = atomic64_read(v);
do {
} while (!atomic64_try_cmpxchg(v, &val, val & i));
return val;
}
#define ATOMIC64_OPS(op, c_op) \
ATOMIC64_OP(op) \
ATOMIC64_FETCH_OP(op, c_op)
static inline void atomic64_or(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "orq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
ATOMIC64_OPS(and, &)
ATOMIC64_OPS(or, |)
ATOMIC64_OPS(xor, ^)
static inline long atomic64_fetch_or(long i, atomic64_t *v)
{
long val = atomic64_read(v);
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP
do {
} while (!atomic64_try_cmpxchg(v, &val, val | i));
return val;
}
static inline void atomic64_xor(long i, atomic64_t *v)
{
asm volatile(LOCK_PREFIX "xorq %1,%0"
: "+m" (v->counter)
: "er" (i)
: "memory");
}
static inline long atomic64_fetch_xor(long i, atomic64_t *v)
{
long val = atomic64_read(v);
do {
} while (!atomic64_try_cmpxchg(v, &val, val ^ i));
return val;
}
#endif /* _ASM_X86_ATOMIC64_64_H */