From 2ceebc035082a42f1416d4b47270c0acb5354949 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 6 Jul 2018 15:16:12 -0700 Subject: [PATCH] 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: Paul E. McKenney --- kernel/rcu/rcutorture.c | 32 ++++++++++++++++++++++---------- 1 file changed, 22 insertions(+), 10 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index c55d1483886e..1bc0e37dffa8 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -66,13 +66,16 @@ MODULE_AUTHOR("Paul E. McKenney and Josh Triplett 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))