mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Dmitry Vyukov](/assets/img/avatar_default.png)
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>
381 lines
8.7 KiB
C
381 lines
8.7 KiB
C
#ifndef _ASM_X86_ATOMIC64_32_H
|
|
#define _ASM_X86_ATOMIC64_32_H
|
|
|
|
#include <linux/compiler.h>
|
|
#include <linux/types.h>
|
|
//#include <asm/cmpxchg.h>
|
|
|
|
/* An 64bit atomic type */
|
|
|
|
typedef struct {
|
|
u64 __aligned(8) counter;
|
|
} atomic64_t;
|
|
|
|
#define ATOMIC64_INIT(val) { (val) }
|
|
|
|
#define __ATOMIC64_DECL(sym) void atomic64_##sym(atomic64_t *, ...)
|
|
#ifndef ATOMIC64_EXPORT
|
|
#define ATOMIC64_DECL_ONE __ATOMIC64_DECL
|
|
#else
|
|
#define ATOMIC64_DECL_ONE(sym) __ATOMIC64_DECL(sym); \
|
|
ATOMIC64_EXPORT(atomic64_##sym)
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_CMPXCHG64
|
|
#define __alternative_atomic64(f, g, out, in...) \
|
|
asm volatile("call %P[func]" \
|
|
: out : [func] "i" (atomic64_##g##_cx8), ## in)
|
|
|
|
#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8)
|
|
#else
|
|
#define __alternative_atomic64(f, g, out, in...) \
|
|
alternative_call(atomic64_##f##_386, atomic64_##g##_cx8, \
|
|
X86_FEATURE_CX8, ASM_OUTPUT2(out), ## in)
|
|
|
|
#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8); \
|
|
ATOMIC64_DECL_ONE(sym##_386)
|
|
|
|
ATOMIC64_DECL_ONE(add_386);
|
|
ATOMIC64_DECL_ONE(sub_386);
|
|
ATOMIC64_DECL_ONE(inc_386);
|
|
ATOMIC64_DECL_ONE(dec_386);
|
|
#endif
|
|
|
|
#define alternative_atomic64(f, out, in...) \
|
|
__alternative_atomic64(f, f, ASM_OUTPUT2(out), ## in)
|
|
|
|
ATOMIC64_DECL(read);
|
|
ATOMIC64_DECL(set);
|
|
ATOMIC64_DECL(xchg);
|
|
ATOMIC64_DECL(add_return);
|
|
ATOMIC64_DECL(sub_return);
|
|
ATOMIC64_DECL(inc_return);
|
|
ATOMIC64_DECL(dec_return);
|
|
ATOMIC64_DECL(dec_if_positive);
|
|
ATOMIC64_DECL(inc_not_zero);
|
|
ATOMIC64_DECL(add_unless);
|
|
|
|
#undef ATOMIC64_DECL
|
|
#undef ATOMIC64_DECL_ONE
|
|
#undef __ATOMIC64_DECL
|
|
#undef ATOMIC64_EXPORT
|
|
|
|
/**
|
|
* atomic64_cmpxchg - cmpxchg atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
* @o: expected value
|
|
* @n: new value
|
|
*
|
|
* Atomically sets @v to @n if it was equal to @o and returns
|
|
* the old value.
|
|
*/
|
|
|
|
static inline long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n)
|
|
{
|
|
return cmpxchg64(&v->counter, o, n);
|
|
}
|
|
|
|
/**
|
|
* atomic64_xchg - xchg atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
* @n: value to assign
|
|
*
|
|
* Atomically xchgs the value of @v to @n and returns
|
|
* the old value.
|
|
*/
|
|
static inline long long atomic64_xchg(atomic64_t *v, long long n)
|
|
{
|
|
long long o;
|
|
unsigned high = (unsigned)(n >> 32);
|
|
unsigned low = (unsigned)n;
|
|
alternative_atomic64(xchg, "=&A" (o),
|
|
"S" (v), "b" (low), "c" (high)
|
|
: "memory");
|
|
return o;
|
|
}
|
|
|
|
/**
|
|
* atomic64_set - set atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
* @i: value to assign
|
|
*
|
|
* Atomically sets the value of @v to @n.
|
|
*/
|
|
static inline void atomic64_set(atomic64_t *v, long long i)
|
|
{
|
|
unsigned high = (unsigned)(i >> 32);
|
|
unsigned low = (unsigned)i;
|
|
alternative_atomic64(set, /* no output */,
|
|
"S" (v), "b" (low), "c" (high)
|
|
: "eax", "edx", "memory");
|
|
}
|
|
|
|
/**
|
|
* atomic64_read - read atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically reads the value of @v and returns it.
|
|
*/
|
|
static inline long long atomic64_read(const atomic64_t *v)
|
|
{
|
|
long long r;
|
|
alternative_atomic64(read, "=&A" (r), "c" (v) : "memory");
|
|
return r;
|
|
}
|
|
|
|
/**
|
|
* atomic64_add_return - add and return
|
|
* @i: integer value to add
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically adds @i to @v and returns @i + *@v
|
|
*/
|
|
static inline long long atomic64_add_return(long long i, atomic64_t *v)
|
|
{
|
|
alternative_atomic64(add_return,
|
|
ASM_OUTPUT2("+A" (i), "+c" (v)),
|
|
ASM_NO_INPUT_CLOBBER("memory"));
|
|
return i;
|
|
}
|
|
|
|
/*
|
|
* Other variants with different arithmetic operators:
|
|
*/
|
|
static inline long long atomic64_sub_return(long long i, atomic64_t *v)
|
|
{
|
|
alternative_atomic64(sub_return,
|
|
ASM_OUTPUT2("+A" (i), "+c" (v)),
|
|
ASM_NO_INPUT_CLOBBER("memory"));
|
|
return i;
|
|
}
|
|
|
|
static inline long long atomic64_inc_return(atomic64_t *v)
|
|
{
|
|
long long a;
|
|
alternative_atomic64(inc_return, "=&A" (a),
|
|
"S" (v) : "memory", "ecx");
|
|
return a;
|
|
}
|
|
|
|
static inline long long atomic64_dec_return(atomic64_t *v)
|
|
{
|
|
long long a;
|
|
alternative_atomic64(dec_return, "=&A" (a),
|
|
"S" (v) : "memory", "ecx");
|
|
return a;
|
|
}
|
|
|
|
/**
|
|
* atomic64_add - add integer to atomic64 variable
|
|
* @i: integer value to add
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically adds @i to @v.
|
|
*/
|
|
static inline long long atomic64_add(long long i, atomic64_t *v)
|
|
{
|
|
__alternative_atomic64(add, add_return,
|
|
ASM_OUTPUT2("+A" (i), "+c" (v)),
|
|
ASM_NO_INPUT_CLOBBER("memory"));
|
|
return i;
|
|
}
|
|
|
|
/**
|
|
* atomic64_sub - subtract the atomic64 variable
|
|
* @i: integer value to subtract
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically subtracts @i from @v.
|
|
*/
|
|
static inline long long atomic64_sub(long long i, atomic64_t *v)
|
|
{
|
|
__alternative_atomic64(sub, sub_return,
|
|
ASM_OUTPUT2("+A" (i), "+c" (v)),
|
|
ASM_NO_INPUT_CLOBBER("memory"));
|
|
return i;
|
|
}
|
|
|
|
/**
|
|
* atomic64_sub_and_test - subtract value from variable and test result
|
|
* @i: integer value to subtract
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically subtracts @i from @v and returns
|
|
* true if the result is zero, or false for all
|
|
* other cases.
|
|
*/
|
|
static inline int atomic64_sub_and_test(long long i, atomic64_t *v)
|
|
{
|
|
return atomic64_sub_return(i, v) == 0;
|
|
}
|
|
|
|
/**
|
|
* atomic64_inc - increment atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically increments @v by 1.
|
|
*/
|
|
static inline void atomic64_inc(atomic64_t *v)
|
|
{
|
|
__alternative_atomic64(inc, inc_return, /* no output */,
|
|
"S" (v) : "memory", "eax", "ecx", "edx");
|
|
}
|
|
|
|
/**
|
|
* atomic64_dec - decrement atomic64 variable
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically decrements @v by 1.
|
|
*/
|
|
static inline void atomic64_dec(atomic64_t *v)
|
|
{
|
|
__alternative_atomic64(dec, dec_return, /* no output */,
|
|
"S" (v) : "memory", "eax", "ecx", "edx");
|
|
}
|
|
|
|
/**
|
|
* atomic64_dec_and_test - decrement and test
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically decrements @v by 1 and
|
|
* returns true if the result is 0, or false for all other
|
|
* cases.
|
|
*/
|
|
static inline int atomic64_dec_and_test(atomic64_t *v)
|
|
{
|
|
return atomic64_dec_return(v) == 0;
|
|
}
|
|
|
|
/**
|
|
* atomic64_inc_and_test - increment and test
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically increments @v by 1
|
|
* and returns true if the result is zero, or false for all
|
|
* other cases.
|
|
*/
|
|
static inline int atomic64_inc_and_test(atomic64_t *v)
|
|
{
|
|
return atomic64_inc_return(v) == 0;
|
|
}
|
|
|
|
/**
|
|
* atomic64_add_negative - add and test if negative
|
|
* @i: integer value to add
|
|
* @v: pointer to type atomic64_t
|
|
*
|
|
* Atomically adds @i to @v and returns true
|
|
* if the result is negative, or false when
|
|
* result is greater than or equal to zero.
|
|
*/
|
|
static inline int atomic64_add_negative(long long i, atomic64_t *v)
|
|
{
|
|
return atomic64_add_return(i, v) < 0;
|
|
}
|
|
|
|
/**
|
|
* atomic64_add_unless - add unless the number is a given value
|
|
* @v: pointer of type atomic64_t
|
|
* @a: the amount to add to v...
|
|
* @u: ...unless v is equal to u.
|
|
*
|
|
* Atomically adds @a to @v, so long as it was not @u.
|
|
* Returns non-zero if the add was done, zero otherwise.
|
|
*/
|
|
static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
|
|
{
|
|
unsigned low = (unsigned)u;
|
|
unsigned high = (unsigned)(u >> 32);
|
|
alternative_atomic64(add_unless,
|
|
ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)),
|
|
"S" (v) : "memory");
|
|
return (int)a;
|
|
}
|
|
|
|
|
|
static inline int atomic64_inc_not_zero(atomic64_t *v)
|
|
{
|
|
int r;
|
|
alternative_atomic64(inc_not_zero, "=&a" (r),
|
|
"S" (v) : "ecx", "edx", "memory");
|
|
return r;
|
|
}
|
|
|
|
static inline long long atomic64_dec_if_positive(atomic64_t *v)
|
|
{
|
|
long long r;
|
|
alternative_atomic64(dec_if_positive, "=&A" (r),
|
|
"S" (v) : "ecx", "memory");
|
|
return r;
|
|
}
|
|
|
|
#undef alternative_atomic64
|
|
#undef __alternative_atomic64
|
|
|
|
static inline void atomic64_and(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c & i)) != c)
|
|
c = old;
|
|
}
|
|
|
|
static inline long long atomic64_fetch_and(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c & i)) != c)
|
|
c = old;
|
|
|
|
return old;
|
|
}
|
|
|
|
static inline void atomic64_or(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c | i)) != c)
|
|
c = old;
|
|
}
|
|
|
|
static inline long long atomic64_fetch_or(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c | i)) != c)
|
|
c = old;
|
|
|
|
return old;
|
|
}
|
|
|
|
static inline void atomic64_xor(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c ^ i)) != c)
|
|
c = old;
|
|
}
|
|
|
|
static inline long long atomic64_fetch_xor(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c ^ i)) != c)
|
|
c = old;
|
|
|
|
return old;
|
|
}
|
|
|
|
static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
|
|
{
|
|
long long old, c = 0;
|
|
|
|
while ((old = atomic64_cmpxchg(v, c, c + i)) != c)
|
|
c = old;
|
|
|
|
return old;
|
|
}
|
|
|
|
#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
|
|
|
|
#endif /* _ASM_X86_ATOMIC64_32_H */
|