Commit 2ceebc03 authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

rcutorture: Add RCU-bh and RCU-sched support for extended readers 



Since there is now a single consolidated RCU flavor, rcutorture
needs to test extending of RCU readers via rcu_read_lock_bh() and
rcu_read_lock_sched().  This commit adds this support, with added checks
(just like for local_bh_enable()) to ensure that rcu_read_unlock_bh()
will not be invoked while interrupts are disabled.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
parent a8bb74ac

kernel/rcu/rcutorture.c

+22 −10
Original line number Diff line number Diff line
@@ -66,13 +66,16 @@ MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@jos 
/* Bits for ->extendables field, extendables param, and related definitions. */

#define RCUTORTURE_RDR_SHIFT	 8	/* Put SRCU index in upper bits. */

#define RCUTORTURE_RDR_MASK	 ((1 << RCUTORTURE_RDR_SHIFT) - 1)

#define RCUTORTURE_RDR_BH	 0x1	/* Extend readers by disabling bh. */

#define RCUTORTURE_RDR_IRQ	 0x2	/*  ... disabling interrupts. */

#define RCUTORTURE_RDR_PREEMPT	 0x4	/*  ... disabling preemption. */

#define RCUTORTURE_RDR_RCU	 0x8	/*  ... entering another RCU reader. */

#define RCUTORTURE_RDR_NBITS	 4	/* Number of bits defined above. */

#define RCUTORTURE_MAX_EXTEND	 (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ | \

				  RCUTORTURE_RDR_PREEMPT)

#define RCUTORTURE_RDR_BH	 0x01	/* Extend readers by disabling bh. */

#define RCUTORTURE_RDR_IRQ	 0x02	/*  ... disabling interrupts. */

#define RCUTORTURE_RDR_PREEMPT	 0x04	/*  ... disabling preemption. */

#define RCUTORTURE_RDR_RBH	 0x08	/*  ... rcu_read_lock_bh(). */

#define RCUTORTURE_RDR_SCHED	 0x10	/*  ... rcu_read_lock_sched(). */

#define RCUTORTURE_RDR_RCU	 0x20	/*  ... entering another RCU reader. */

#define RCUTORTURE_RDR_NBITS	 6	/* Number of bits defined above. */

#define RCUTORTURE_MAX_EXTEND	 \

	(RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ | RCUTORTURE_RDR_PREEMPT | \

	 RCUTORTURE_RDR_RBH | RCUTORTURE_RDR_SCHED)

#define RCUTORTURE_RDR_MAX_LOOPS 0x7	/* Maximum reader extensions. */

					/* Must be power of two minus one. */
@@ -1217,6 +1220,10 @@ static void rcutorture_one_extend(int *readstate, int newstate, 
		local_irq_disable();

	if (statesnew & RCUTORTURE_RDR_PREEMPT)

		preempt_disable();

	if (statesnew & RCUTORTURE_RDR_RBH)

		rcu_read_lock_bh();

	if (statesnew & RCUTORTURE_RDR_SCHED)

		rcu_read_lock_sched();

	if (statesnew & RCUTORTURE_RDR_RCU)

		idxnew = cur_ops->readlock() << RCUTORTURE_RDR_SHIFT;
@@ -1227,6 +1234,10 @@ static void rcutorture_one_extend(int *readstate, int newstate, 
		local_bh_enable();

	if (statesold & RCUTORTURE_RDR_PREEMPT)

		preempt_enable();

	if (statesold & RCUTORTURE_RDR_RBH)

		rcu_read_unlock_bh();

	if (statesold & RCUTORTURE_RDR_SCHED)

		rcu_read_unlock_sched();

	if (statesold & RCUTORTURE_RDR_RCU)

		cur_ops->readunlock(idxold >> RCUTORTURE_RDR_SHIFT);
@@ -1269,10 +1280,11 @@ rcutorture_extend_mask(int oldmask, struct torture_random_state *trsp) 
		mask = mask & randmask2;

	else

		mask = mask & (1 << (randmask2 % RCUTORTURE_RDR_NBITS));

	/* Can't enable bh w/irq disabled. */

	if ((mask & RCUTORTURE_RDR_IRQ) &&

	    !(mask & RCUTORTURE_RDR_BH) &&

	    (oldmask & RCUTORTURE_RDR_BH))

		mask |= RCUTORTURE_RDR_BH; /* Can't enable bh w/irq disabled. */

	    ((!(mask & RCUTORTURE_RDR_BH) && (oldmask & RCUTORTURE_RDR_BH)) ||

	     (!(mask & RCUTORTURE_RDR_RBH) && (oldmask & RCUTORTURE_RDR_RBH))))

		mask |= RCUTORTURE_RDR_BH | RCUTORTURE_RDR_RBH;

	if ((mask & RCUTORTURE_RDR_IRQ) &&

	    !(mask & cur_ops->ext_irq_conflict) &&

	    (oldmask & cur_ops->ext_irq_conflict))

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