From: "Paul E. McKenney" <paulmck@kernel.org>
To: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com,
mingo@kernel.org, jiangshanlai@gmail.com,
akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org,
"Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 01/17] rcutorture: Sanitize RCUTORTURE_RDR_MASK
Date: Wed, 1 Dec 2021 16:43:20 -0800 [thread overview]
Message-ID: <20211202004337.3130175-1-paulmck@kernel.org> (raw)
In-Reply-To: <20211202004245.GA3129966@paulmck-ThinkPad-P17-Gen-1>
RCUTORTURE_RDR_MASK is currently not the bit indicated by
RCUTORTURE_RDR_SHIFT, but is instead all the bits less significant than
that one. This is an accident waiting to happen, so this commit makes
RCUTORTURE_RDR_MASK be that one bit and adjusts uses accordingly.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/rcutorture.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 8b410d982990c..1e03fe681f025 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -54,7 +54,7 @@ MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com> and Josh Triplett <josh@
/* 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_MASK (1 << RCUTORTURE_RDR_SHIFT)
#define RCUTORTURE_RDR_BH 0x01 /* Extend readers by disabling bh. */
#define RCUTORTURE_RDR_IRQ 0x02 /* ... disabling interrupts. */
#define RCUTORTURE_RDR_PREEMPT 0x04 /* ... disabling preemption. */
@@ -1466,6 +1466,7 @@ static void rcutorture_one_extend(int *readstate, int newstate,
if (lockit)
raw_spin_lock_irqsave(¤t->pi_lock, flags);
cur_ops->readunlock(idxold >> RCUTORTURE_RDR_SHIFT);
+ idxold = 0;
if (lockit)
raw_spin_unlock_irqrestore(¤t->pi_lock, flags);
}
@@ -1476,7 +1477,7 @@ static void rcutorture_one_extend(int *readstate, int newstate,
/* Update the reader state. */
if (idxnew == -1)
- idxnew = idxold & ~RCUTORTURE_RDR_MASK;
+ idxnew = idxold & RCUTORTURE_RDR_MASK;
WARN_ON_ONCE(idxnew < 0);
WARN_ON_ONCE((idxnew >> RCUTORTURE_RDR_SHIFT) > 1);
*readstate = idxnew | newstate;
@@ -1626,7 +1627,7 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp, long myid)
rcu_torture_writer_state,
cookie, cur_ops->get_gp_state());
rcutorture_one_extend(&readstate, 0, trsp, rtrsp);
- WARN_ON_ONCE(readstate & RCUTORTURE_RDR_MASK);
+ WARN_ON_ONCE(readstate);
// This next splat is expected behavior if leakpointer, especially
// for CONFIG_RCU_STRICT_GRACE_PERIOD=y kernels.
WARN_ON_ONCE(leakpointer && READ_ONCE(p->rtort_pipe_count) > 1);
--
2.31.1.189.g2e36527f23
next prev parent reply other threads:[~2021-12-02 0:44 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-02 0:42 [PATCH rcu 0/17] Torture-test updates for v5.17 Paul E. McKenney
2021-12-02 0:43 ` Paul E. McKenney [this message]
2021-12-02 0:43 ` [PATCH rcu 02/17] rcutorture: More thoroughly test nested readers Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 03/17] rcutorture: Suppress pi-lock-across read-unlock testing for Tiny SRCU Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 04/17] refscale: Simplify the errexit checkpoint Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 05/17] refscale: Prevent buffer to pr_alert() being too long Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 06/17] refscale: Always log the error message Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 07/17] refscale: Add missing '\n' to flush message Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 08/17] scftorture: " Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 09/17] scftorture: Remove unused SCFTORTOUT Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 10/17] rcuscale: Always log error message Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 11/17] scftorture: " Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 12/17] locktorture,rcutorture,torture: " Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 13/17] rcutorture: Avoid soft lockup during cpu stall Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 14/17] rcutorture: Test RCU-tasks multiqueue callback queueing Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 15/17] rcutorture: Enable multiple concurrent callback-flood kthreads Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 16/17] rcutorture: Add ability to limit callback-flood intensity Paul E. McKenney
2021-12-02 0:43 ` [PATCH rcu 17/17] rcutorture: Combine n_max_cbs from all kthreads in a callback flood Paul E. McKenney
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