This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			101 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			101 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef _ALPHA_LOCAL_H
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#define _ALPHA_LOCAL_H
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#include <linux/percpu.h>
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#include <linux/atomic.h>
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typedef struct
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{
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	atomic_long_t a;
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} local_t;
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#define LOCAL_INIT(i)	{ ATOMIC_LONG_INIT(i) }
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#define local_read(l)	atomic_long_read(&(l)->a)
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#define local_set(l,i)	atomic_long_set(&(l)->a, (i))
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#define local_inc(l)	atomic_long_inc(&(l)->a)
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#define local_dec(l)	atomic_long_dec(&(l)->a)
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#define local_add(i,l)	atomic_long_add((i),(&(l)->a))
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#define local_sub(i,l)	atomic_long_sub((i),(&(l)->a))
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static __inline__ long local_add_return(long i, local_t * l)
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{
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	long temp, result;
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	__asm__ __volatile__(
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	"1:	ldq_l %0,%1\n"
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	"	addq %0,%3,%2\n"
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	"	addq %0,%3,%0\n"
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	"	stq_c %0,%1\n"
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	"	beq %0,2f\n"
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	".subsection 2\n"
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	"2:	br 1b\n"
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	".previous"
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	:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
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	:"Ir" (i), "m" (l->a.counter) : "memory");
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	return result;
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}
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static __inline__ long local_sub_return(long i, local_t * l)
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{
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	long temp, result;
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	__asm__ __volatile__(
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	"1:	ldq_l %0,%1\n"
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	"	subq %0,%3,%2\n"
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	"	subq %0,%3,%0\n"
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	"	stq_c %0,%1\n"
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	"	beq %0,2f\n"
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	".subsection 2\n"
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	"2:	br 1b\n"
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	".previous"
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	:"=&r" (temp), "=m" (l->a.counter), "=&r" (result)
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	:"Ir" (i), "m" (l->a.counter) : "memory");
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	return result;
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}
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#define local_cmpxchg(l, o, n) \
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	(cmpxchg_local(&((l)->a.counter), (o), (n)))
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#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
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/**
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 * local_add_unless - add unless the number is a given value
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 * @l: pointer of type local_t
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 * @a: the amount to add to l...
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 * @u: ...unless l is equal to u.
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 *
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 * Atomically adds @a to @l, so long as it was not @u.
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 * Returns non-zero if @l was not @u, and zero otherwise.
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 */
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#define local_add_unless(l, a, u)				\
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({								\
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	long c, old;						\
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	c = local_read(l);					\
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	for (;;) {						\
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		if (unlikely(c == (u)))				\
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			break;					\
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		old = local_cmpxchg((l), c, c + (a));	\
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		if (likely(old == c))				\
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			break;					\
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		c = old;					\
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	}							\
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	c != (u);						\
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})
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#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
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#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)
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#define local_dec_return(l) local_sub_return(1,(l))
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#define local_inc_return(l) local_add_return(1,(l))
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#define local_sub_and_test(i,l) (local_sub_return((i), (l)) == 0)
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#define local_inc_and_test(l) (local_add_return(1, (l)) == 0)
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#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
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/* Verify if faster than atomic ops */
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#define __local_inc(l)		((l)->a.counter++)
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#define __local_dec(l)		((l)->a.counter++)
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#define __local_add(i,l)	((l)->a.counter+=(i))
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#define __local_sub(i,l)	((l)->a.counter-=(i))
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#endif /* _ALPHA_LOCAL_H */
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