rcuwait: avoid lockdep splats from rcuwait_active()

rcuwait_active only returns whether w->task is not NULL. This is exactly one of the usecases that are mentioned in the documentation for rcu_access_pointer() where it is correct to bypass lockdep checks. This avoids a splat from kvm_vcpu_on_spin().

Paolo Bonzini committed 6 years ago

Commit febd6681 parent cb953121 file · +1 −1Browse files

Showing the changes to include/linux (1 of 1 file). Show all

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include/linux/rcuwait.h+1−1

@@ -31,7 +31,7 @@ static inline void rcuwait_init(struct rcuwait *w) · 30 unmodified lines
31	*/	31	*/
32	static inline int rcuwait_active(struct rcuwait *w)	32	static inline int rcuwait_active(struct rcuwait *w)
33	{	33	{
34	return !!rcu_dereference(w->task);	34	return !!rcu_access_pointer(w->task);
35	}	35	}
36		36
37	extern int rcuwait_wake_up(struct rcuwait *w);	37	extern int rcuwait_wake_up(struct rcuwait *w);