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authorPaul E. McKenney <paulmck@kernel.org>2020-10-09 19:51:55 -0700
committerPaul E. McKenney <paulmck@kernel.org>2020-11-06 17:13:57 -0800
commita7eb937b67b64b8b4645f1ebca3ac2079c6de81b (patch)
tree37a9c9aa377bef48b7075450da31cee4590c1a80 /kernel/rcu
parent0d7202876bcb968a68f5608b9ff7a824fbc7e94d (diff)
downloadlinux-a7eb937b67b64b8b4645f1ebca3ac2079c6de81b.tar.bz2
rcutorture: Don't do need_resched() testing if ->sync is NULL
If cur_ops->sync is NULL, rcu_torture_fwd_prog_nr() will nevertheless attempt to call through it. This commit therefore flags cases where neither need_resched() nor call_rcu() forward-progress testing can be performed due to NULL function pointers, and also causes rcu_torture_fwd_prog_nr() to take an early exit if cur_ops->sync() is NULL. Reported-by: Tom Rix <trix@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu')
-rw-r--r--kernel/rcu/rcutorture.c8
1 files changed, 5 insertions, 3 deletions
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index e7d52fded3cd..4dfd113882aa 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1923,7 +1923,9 @@ static void rcu_torture_fwd_prog_nr(struct rcu_fwd *rfp,
unsigned long stopat;
static DEFINE_TORTURE_RANDOM(trs);
- if (cur_ops->call && cur_ops->sync && cur_ops->cb_barrier) {
+ if (!cur_ops->sync)
+ return; // Cannot do need_resched() forward progress testing without ->sync.
+ if (cur_ops->call && cur_ops->cb_barrier) {
init_rcu_head_on_stack(&fcs.rh);
selfpropcb = true;
}
@@ -2149,8 +2151,8 @@ static int __init rcu_torture_fwd_prog_init(void)
if (!fwd_progress)
return 0; /* Not requested, so don't do it. */
- if (!cur_ops->stall_dur || cur_ops->stall_dur() <= 0 ||
- cur_ops == &rcu_busted_ops) {
+ if ((!cur_ops->sync && !cur_ops->call) ||
+ !cur_ops->stall_dur || cur_ops->stall_dur() <= 0 || cur_ops == &rcu_busted_ops) {
VERBOSE_TOROUT_STRING("rcu_torture_fwd_prog_init: Disabled, unsupported by RCU flavor under test");
return 0;
}