31 lines
		
	
	
		
			482 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			31 lines
		
	
	
		
			482 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
C MP+fencewmbonceonce+fencermbonceonce
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(*
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 * Result: Never
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 *
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 * This litmus test demonstrates that smp_wmb() and smp_rmb() provide
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 * sufficient ordering for the message-passing pattern.  However, it
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 * is usually better to use smp_store_release() and smp_load_acquire().
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 *)
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{}
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P0(int *x, int *y)
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{
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	WRITE_ONCE(*x, 1);
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	smp_wmb();
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	WRITE_ONCE(*y, 1);
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}
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P1(int *x, int *y)
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{
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	int r0;
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	int r1;
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	r0 = READ_ONCE(*y);
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	smp_rmb();
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	r1 = READ_ONCE(*x);
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}
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exists (1:r0=1 /\ 1:r1=0)
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