rcutorture: Abstract read-lock-held checks

This commit adds a (*readlock_held)() function pointer to the
rcu_torture_ops structure in order to make the rcu_torture_one_read()
function's rcu_dereference_check() lockdep expression more appropriate
for a given run.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 29d2f4c..bf488f9 100644 (file)
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -331,6 +331,7 @@ struct rcu_torture_ops {
        void (*read_delay)(struct torture_random_state *rrsp,
                           struct rt_read_seg *rtrsp);
        void (*readunlock)(int idx);
+       int (*readlock_held)(void);
        unsigned long (*get_gp_seq)(void);
        unsigned long (*gp_diff)(unsigned long new, unsigned long old);
        void (*deferred_free)(struct rcu_torture *p);
@@ -359,6 +360,11 @@ static struct rcu_torture_ops *cur_ops;
  * Definitions for rcu torture testing.
  */
 
+static int torture_readlock_not_held(void)
+{
+       return rcu_read_lock_bh_held() || rcu_read_lock_sched_held();
+}
+
 static int rcu_torture_read_lock(void) __acquires(RCU)
 {
        rcu_read_lock();
@@ -488,6 +494,7 @@ static struct rcu_torture_ops rcu_ops = {
        .readlock       = rcu_torture_read_lock,
        .read_delay     = rcu_read_delay,
        .readunlock     = rcu_torture_read_unlock,
+       .readlock_held  = torture_readlock_not_held,
        .get_gp_seq     = rcu_get_gp_seq,
        .gp_diff        = rcu_seq_diff,
        .deferred_free  = rcu_torture_deferred_free,
@@ -540,6 +547,7 @@ static struct rcu_torture_ops rcu_busted_ops = {
        .readlock       = rcu_torture_read_lock,
        .read_delay     = rcu_read_delay,  /* just reuse rcu's version. */
        .readunlock     = rcu_torture_read_unlock,
+       .readlock_held  = torture_readlock_not_held,
        .get_gp_seq     = rcu_no_completed,
        .deferred_free  = rcu_busted_torture_deferred_free,
        .sync           = synchronize_rcu_busted,
@@ -589,6 +597,11 @@ static void srcu_torture_read_unlock(int idx) __releases(srcu_ctlp)
        srcu_read_unlock(srcu_ctlp, idx);
 }
 
+static int torture_srcu_read_lock_held(void)
+{
+       return srcu_read_lock_held(srcu_ctlp);
+}
+
 static unsigned long srcu_torture_completed(void)
 {
        return srcu_batches_completed(srcu_ctlp);
@@ -646,6 +659,7 @@ static struct rcu_torture_ops srcu_ops = {
        .readlock       = srcu_torture_read_lock,
        .read_delay     = srcu_read_delay,
        .readunlock     = srcu_torture_read_unlock,
+       .readlock_held  = torture_srcu_read_lock_held,
        .get_gp_seq     = srcu_torture_completed,
        .deferred_free  = srcu_torture_deferred_free,
        .sync           = srcu_torture_synchronize,
@@ -681,6 +695,7 @@ static struct rcu_torture_ops srcud_ops = {
        .readlock       = srcu_torture_read_lock,
        .read_delay     = srcu_read_delay,
        .readunlock     = srcu_torture_read_unlock,
+       .readlock_held  = torture_srcu_read_lock_held,
        .get_gp_seq     = srcu_torture_completed,
        .deferred_free  = srcu_torture_deferred_free,
        .sync           = srcu_torture_synchronize,
@@ -700,6 +715,7 @@ static struct rcu_torture_ops busted_srcud_ops = {
        .readlock       = srcu_torture_read_lock,
        .read_delay     = rcu_read_delay,
        .readunlock     = srcu_torture_read_unlock,
+       .readlock_held  = torture_srcu_read_lock_held,
        .get_gp_seq     = srcu_torture_completed,
        .deferred_free  = srcu_torture_deferred_free,
        .sync           = srcu_torture_synchronize,
@@ -787,6 +803,7 @@ static struct rcu_torture_ops trivial_ops = {
        .readlock       = rcu_torture_read_lock_trivial,
        .read_delay     = rcu_read_delay,  /* just reuse rcu's version. */
        .readunlock     = rcu_torture_read_unlock_trivial,
+       .readlock_held  = torture_readlock_not_held,
        .get_gp_seq     = rcu_no_completed,
        .sync           = synchronize_rcu_trivial,
        .exp_sync       = synchronize_rcu_trivial,
@@ -850,6 +867,7 @@ static struct rcu_torture_ops tasks_tracing_ops = {
        .readlock       = tasks_tracing_torture_read_lock,
        .read_delay     = srcu_read_delay,  /* just reuse srcu's version. */
        .readunlock     = tasks_tracing_torture_read_unlock,
+       .readlock_held  = rcu_read_lock_trace_held,
        .get_gp_seq     = rcu_no_completed,
        .deferred_free  = rcu_tasks_tracing_torture_deferred_free,
        .sync           = synchronize_rcu_tasks_trace,
@@ -871,11 +889,6 @@ static unsigned long rcutorture_seq_diff(unsigned long new, unsigned long old)
        return cur_ops->gp_diff(new, old);
 }
 
-static bool __maybe_unused torturing_tasks(void)
-{
-       return cur_ops == &tasks_ops || cur_ops == &tasks_rude_ops;
-}
-
 /*
  * RCU torture priority-boost testing.  Runs one real-time thread per
  * CPU for moderate bursts, repeatedly registering RCU callbacks and
@@ -1553,11 +1566,7 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp, long myid)
        started = cur_ops->get_gp_seq();
        ts = rcu_trace_clock_local();
        p = rcu_dereference_check(rcu_torture_current,
-                                 rcu_read_lock_bh_held() ||
-                                 rcu_read_lock_sched_held() ||
-                                 srcu_read_lock_held(srcu_ctlp) ||
-                                 rcu_read_lock_trace_held() ||
-                                 torturing_tasks());
+                                 !cur_ops->readlock_held || cur_ops->readlock_held());
        if (p == NULL) {
                /* Wait for rcu_torture_writer to get underway */
                rcutorture_one_extend(&readstate, 0, trsp, rtrsp);