35 lines
		
	
	
		
			555 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			555 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| C MP+onceassign+derefonce
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| 
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| (*
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|  * Result: Never
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|  *
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|  * This litmus test demonstrates that rcu_assign_pointer() and
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|  * rcu_dereference() suffice to ensure that an RCU reader will not see
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|  * pre-initialization garbage when it traverses an RCU-protected data
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|  * structure containing a newly inserted element.
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|  *)
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| 
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| {
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| y=z;
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| z=0;
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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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| 	rcu_assign_pointer(*y, x);
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| }
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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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| 
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| 	rcu_read_lock();
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| 	r0 = rcu_dereference(*y);
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| 	r1 = READ_ONCE(*r0);
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| 	rcu_read_unlock();
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| }
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| 
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| exists (1:r0=x /\ 1:r1=0)
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