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| author | Paul E. McKenney <paulmck@kernel.org> | 2021-05-25 01:36:37 +0300 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2021-07-20 23:43:44 +0300 |
| commit | f8ab3fad80dddf3f2cecb53983063c4431058ca1 (patch) | |
| tree | ef376a42d0d23f333a4813494900b85c0504afdd /kernel/rcu | |
| parent | bdb0cca0d11060fce8a8a44588ac1470c25d62bc (diff) | |
| download | linux-f8ab3fad80dddf3f2cecb53983063c4431058ca1.tar.xz | |
rcu-tasks: Mark ->trc_reader_special.b.need_qs data races
There are several ->trc_reader_special.b.need_qs data races that are
too low-probability for KCSAN to notice, but which will happen sooner
or later. This commit therefore marks these accesses.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/tasks.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index f6b5320c4484..1cece5e9be9a 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -850,7 +850,7 @@ static DEFINE_IRQ_WORK(rcu_tasks_trace_iw, rcu_read_unlock_iw); /* If we are the last reader, wake up the grace-period kthread. */ void rcu_read_unlock_trace_special(struct task_struct *t, int nesting) { - int nq = t->trc_reader_special.b.need_qs; + int nq = READ_ONCE(t->trc_reader_special.b.need_qs); if (IS_ENABLED(CONFIG_TASKS_TRACE_RCU_READ_MB) && t->trc_reader_special.b.need_mb) @@ -916,7 +916,7 @@ static void trc_read_check_handler(void *t_in) // Get here if the task is in a read-side critical section. Set // its state so that it will awaken the grace-period kthread upon // exit from that critical section. - WARN_ON_ONCE(t->trc_reader_special.b.need_qs); + WARN_ON_ONCE(READ_ONCE(t->trc_reader_special.b.need_qs)); WRITE_ONCE(t->trc_reader_special.b.need_qs, true); reset_ipi: @@ -968,7 +968,7 @@ static bool trc_inspect_reader(struct task_struct *t, void *arg) // state so that it will awaken the grace-period kthread upon exit // from that critical section. atomic_inc(&trc_n_readers_need_end); // One more to wait on. - WARN_ON_ONCE(t->trc_reader_special.b.need_qs); + WARN_ON_ONCE(READ_ONCE(t->trc_reader_special.b.need_qs)); WRITE_ONCE(t->trc_reader_special.b.need_qs, true); return true; } @@ -1103,7 +1103,7 @@ static void show_stalled_task_trace(struct task_struct *t, bool *firstreport) ".i"[is_idle_task(t)], ".N"[cpu > 0 && tick_nohz_full_cpu(cpu)], READ_ONCE(t->trc_reader_nesting), - " N"[!!t->trc_reader_special.b.need_qs], + " N"[!!READ_ONCE(t->trc_reader_special.b.need_qs)], cpu); sched_show_task(t); } |