Commit cfb2c107 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

Merge branches 'doc.2020.08.24a', 'fixes.2020.09.03b' and 'torture.2020.08.24a' into HEAD 

doc.2020.08.24a: Documentation updates.
fixes.2020.09.03b: Miscellaneous fixes.
torture.2020.08.24a: Torture-test updates.
parents 7f45d6f8 70060b87 b67a9170

Documentation/admin-guide/kernel-parameters.txt

+12 −0
Original line number Diff line number Diff line
@@ -4269,6 +4269,18 @@ 
			are zero, rcutorture acts as if is interpreted

			they are all non-zero.



	rcutorture.irqreader= [KNL]

			Run RCU readers from irq handlers, or, more

			accurately, from a timer handler.  Not all RCU

			flavors take kindly to this sort of thing.



	rcutorture.leakpointer= [KNL]

			Leak an RCU-protected pointer out of the reader.

			This can of course result in splats, and is

			intended to test the ability of things like

			CONFIG_RCU_STRICT_GRACE_PERIOD=y to detect

			such leaks.



	rcutorture.n_barrier_cbs= [KNL]

			Set callbacks/threads for rcu_barrier() testing.

arch/x86/kvm/mmu/page_track.c

+4 −2
Original line number Diff line number Diff line
@@ -229,7 +229,8 @@ void kvm_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new, 
		return;



	idx = srcu_read_lock(&head->track_srcu);

	hlist_for_each_entry_rcu(n, &head->track_notifier_list, node)

	hlist_for_each_entry_srcu(n, &head->track_notifier_list, node,

				srcu_read_lock_held(&head->track_srcu))

		if (n->track_write)

			n->track_write(vcpu, gpa, new, bytes, n);

	srcu_read_unlock(&head->track_srcu, idx);
@@ -254,7 +255,8 @@ void kvm_page_track_flush_slot(struct kvm *kvm, struct kvm_memory_slot *slot) 
		return;



	idx = srcu_read_lock(&head->track_srcu);

	hlist_for_each_entry_rcu(n, &head->track_notifier_list, node)

	hlist_for_each_entry_srcu(n, &head->track_notifier_list, node,

				srcu_read_lock_held(&head->track_srcu))

		if (n->track_flush_slot)

			n->track_flush_slot(kvm, slot, n);

	srcu_read_unlock(&head->track_srcu, idx);

include/linux/rculist.h

+48 −0
Original line number Diff line number Diff line
@@ -63,9 +63,17 @@ static inline void INIT_LIST_HEAD_RCU(struct list_head *list) 
	RCU_LOCKDEP_WARN(!(cond) && !rcu_read_lock_any_held(),		\

			 "RCU-list traversed in non-reader section!");	\

	})



#define __list_check_srcu(cond)					 \

	({								 \

	RCU_LOCKDEP_WARN(!(cond),					 \

		"RCU-list traversed without holding the required lock!");\

	})

#else

#define __list_check_rcu(dummy, cond, extra...)				\

	({ check_arg_count_one(extra); })



#define __list_check_srcu(cond) ({ })

#endif



/*
@@ -385,6 +393,25 @@ static inline void list_splice_tail_init_rcu(struct list_head *list, 
		&pos->member != (head);					\

		pos = list_entry_rcu(pos->member.next, typeof(*pos), member))



/**

 * list_for_each_entry_srcu	-	iterate over rcu list of given type

 * @pos:	the type * to use as a loop cursor.

 * @head:	the head for your list.

 * @member:	the name of the list_head within the struct.

 * @cond:	lockdep expression for the lock required to traverse the list.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as list_add_rcu()

 * as long as the traversal is guarded by srcu_read_lock().

 * The lockdep expression srcu_read_lock_held() can be passed as the

 * cond argument from read side.

 */

#define list_for_each_entry_srcu(pos, head, member, cond)		\

	for (__list_check_srcu(cond),					\

	     pos = list_entry_rcu((head)->next, typeof(*pos), member);	\

		&pos->member != (head);					\

		pos = list_entry_rcu(pos->member.next, typeof(*pos), member))



/**

 * list_entry_lockless - get the struct for this entry

 * @ptr:        the &struct list_head pointer.
@@ -683,6 +710,27 @@ static inline void hlist_add_behind_rcu(struct hlist_node *n, 
		pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(\

			&(pos)->member)), typeof(*(pos)), member))



/**

 * hlist_for_each_entry_srcu - iterate over rcu list of given type

 * @pos:	the type * to use as a loop cursor.

 * @head:	the head for your list.

 * @member:	the name of the hlist_node within the struct.

 * @cond:	lockdep expression for the lock required to traverse the list.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as hlist_add_head_rcu()

 * as long as the traversal is guarded by srcu_read_lock().

 * The lockdep expression srcu_read_lock_held() can be passed as the

 * cond argument from read side.

 */

#define hlist_for_each_entry_srcu(pos, head, member, cond)		\

	for (__list_check_srcu(cond),					\

	     pos = hlist_entry_safe(rcu_dereference_raw(hlist_first_rcu(head)),\

			typeof(*(pos)), member);			\

		pos;							\

		pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(\

			&(pos)->member)), typeof(*(pos)), member))



/**

 * hlist_for_each_entry_rcu_notrace - iterate over rcu list of given type (for tracing)

 * @pos:	the type * to use as a loop cursor.

include/linux/rcupdate.h

+6 −6
Original line number Diff line number Diff line
@@ -709,8 +709,8 @@ static inline void rcu_read_lock_bh(void) 
			 "rcu_read_lock_bh() used illegally while idle");

}



/*

 * rcu_read_unlock_bh - marks the end of a softirq-only RCU critical section

/**

 * rcu_read_unlock_bh() - marks the end of a softirq-only RCU critical section

 *

 * See rcu_read_lock_bh() for more information.

 */
@@ -751,10 +751,10 @@ static inline notrace void rcu_read_lock_sched_notrace(void) 
	__acquire(RCU_SCHED);

}



/*

 * rcu_read_unlock_sched - marks the end of a RCU-classic critical section

/**

 * rcu_read_unlock_sched() - marks the end of a RCU-classic critical section

 *

 * See rcu_read_lock_sched for more information.

 * See rcu_read_lock_sched() for more information.

 */

static inline void rcu_read_unlock_sched(void)

{
@@ -945,7 +945,7 @@ static inline void rcu_head_init(struct rcu_head *rhp) 
}



/**

 * rcu_head_after_call_rcu - Has this rcu_head been passed to call_rcu()?

 * rcu_head_after_call_rcu() - Has this rcu_head been passed to call_rcu()?

 * @rhp: The rcu_head structure to test.

 * @f: The function passed to call_rcu() along with @rhp.

 *

include/linux/rcutiny.h

+0 −1
Original line number Diff line number Diff line
@@ -103,7 +103,6 @@ static inline void rcu_scheduler_starting(void) { } 
static inline void rcu_end_inkernel_boot(void) { }

static inline bool rcu_inkernel_boot_has_ended(void) { return true; }

static inline bool rcu_is_watching(void) { return true; }

static inline bool __rcu_is_watching(void) { return true; }

static inline void rcu_momentary_dyntick_idle(void) { }

static inline void kfree_rcu_scheduler_running(void) { }

static inline bool rcu_gp_might_be_stalled(void) { return false; }