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	 0f38c06cab
			
		
	
	
		0f38c06cab
		
	
	
	
	
		
			
			This commit checks to see if the RCU reader has been preempted within its read-side critical section for RCU flavors supporting this notion (currently only preemptible RCU). If such a preemption occurred, then this is printed at the end of the "Failure/close-call rcutorture reader segments" list at the end of the rcutorture run. [ paulmck: Apply kernel test robot feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Frederic Weisbecker <frederic@kernel.org> Tested-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
		
			
				
	
	
		
			79 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			79 lines
		
	
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #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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| #include <linux/sched.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, unsigned int state, 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, state, ...) \
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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, state, ARRAY_SIZE(__crcu_array), __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, TASK_UNINTERRUPTIBLE, __VA_ARGS__)
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| #define wait_rcu_gp_state(state, ...) _wait_rcu_gp(false, state, __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 different grace periods to wait on
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|  *
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|  * This macro waits concurrently for multiple types of RCU grace periods.
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|  * For example, synchronize_rcu_mult(call_rcu, call_rcu_tasks) would wait
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|  * on concurrent RCU and RCU-tasks grace periods.  Waiting on a given 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, with this wrapper supplying the pointer to the
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|  * corresponding srcu_struct.
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|  *
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|  * Note that call_rcu_hurry() should be used instead of call_rcu()
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|  * because in kernels built with CONFIG_RCU_LAZY=y the delay between the
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|  * invocation of call_rcu() and that of the corresponding RCU callback
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|  * can be multiple seconds.
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|  *
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|  * The first argument tells Tiny RCU's _wait_rcu_gp() not to
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|  * bother waiting for RCU.  The reason for this is because anywhere
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|  * synchronize_rcu_mult() can be called is automatically already a full
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|  * 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), TASK_UNINTERRUPTIBLE, __VA_ARGS__)
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| 
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| static inline void cond_resched_rcu(void)
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| {
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| #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
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| 	rcu_read_unlock();
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| 	cond_resched();
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| 	rcu_read_lock();
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| #endif
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| }
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| 
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| // Has the current task blocked within its current RCU read-side
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| // critical section?
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| static inline bool has_rcu_reader_blocked(void)
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| {
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| #ifdef CONFIG_PREEMPT_RCU
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| 	return !list_empty(¤t->rcu_node_entry);
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| #else
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| 	return false;
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| #endif
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| }
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| 
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| #endif /* _LINUX_SCHED_RCUPDATE_WAIT_H */
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