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	 f9411ebe3d
			
		
	
	
		f9411ebe3d
		
	
	
	
	
		
			
			So rcupdate.h is a pretty complex header, in particular it includes <linux/completion.h> which includes <linux/wait.h> - creating a dependency that includes <linux/wait.h> in <linux/sched.h>, which prevents the isolation of <linux/sched.h> from the derived <linux/wait.h> header. Solve part of the problem by decoupling rcupdate.h from completions: this can be done by separating out the rcu_synchronize types and APIs, and updating their usage sites. Since this is a mostly RCU-internal types this will not just simplify <linux/sched.h>'s dependencies, but will make all the hundreds of .c files that include rcupdate.h but not completions or wait.h build faster. ( For rcutiny this means that two dependent APIs have to be uninlined, but that shouldn't be much of a problem as they are rare variants. ) Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
			50 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _LINUX_SCHED_RCUPDATE_WAIT_H
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| #define _LINUX_SCHED_RCUPDATE_WAIT_H
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| 
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| /*
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|  * RCU synchronization types and methods:
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|  */
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| 
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| #include <linux/rcupdate.h>
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| #include <linux/completion.h>
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| 
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| /*
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|  * Structure allowing asynchronous waiting on RCU.
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|  */
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| struct rcu_synchronize {
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| 	struct rcu_head head;
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| 	struct completion completion;
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| };
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| void wakeme_after_rcu(struct rcu_head *head);
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| 
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| void __wait_rcu_gp(bool checktiny, int n, call_rcu_func_t *crcu_array,
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| 		   struct rcu_synchronize *rs_array);
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| 
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| #define _wait_rcu_gp(checktiny, ...) \
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| do {									\
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| 	call_rcu_func_t __crcu_array[] = { __VA_ARGS__ };		\
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| 	struct rcu_synchronize __rs_array[ARRAY_SIZE(__crcu_array)];	\
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| 	__wait_rcu_gp(checktiny, ARRAY_SIZE(__crcu_array),		\
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| 			__crcu_array, __rs_array);			\
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| } while (0)
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| 
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| #define wait_rcu_gp(...) _wait_rcu_gp(false, __VA_ARGS__)
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| 
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| /**
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|  * synchronize_rcu_mult - Wait concurrently for multiple grace periods
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|  * @...: List of call_rcu() functions for the flavors to wait on.
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|  *
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|  * This macro waits concurrently for multiple flavors of RCU grace periods.
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|  * For example, synchronize_rcu_mult(call_rcu, call_rcu_bh) would wait
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|  * on concurrent RCU and RCU-bh grace periods.  Waiting on a give SRCU
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|  * domain requires you to write a wrapper function for that SRCU domain's
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|  * call_srcu() function, supplying the corresponding srcu_struct.
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|  *
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|  * If Tiny RCU, tell _wait_rcu_gp() not to bother waiting for RCU
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|  * or RCU-bh, given that anywhere synchronize_rcu_mult() can be called
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|  * is automatically a grace period.
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|  */
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| #define synchronize_rcu_mult(...) \
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| 	_wait_rcu_gp(IS_ENABLED(CONFIG_TINY_RCU), __VA_ARGS__)
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| 
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| #endif /* _LINUX_SCHED_RCUPDATE_WAIT_H */
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