trace_note_tsk() is called by __blk_add_trace(), which is covered by RCU read lock.
So in case of PREEMPT_RT, warning of 'BUG: sleeping function called from invalid context'
will be triggered because spin lock is converted to rtmutex.
Fix the issue by converting running_trace_lock into raw_spin_lock().
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
kernel/trace/blktrace.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 2c5b3c5317c2..53dc876d669d 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -34,7 +34,7 @@ static struct trace_array *blk_tr;
static bool blk_tracer_enabled __read_mostly;
static LIST_HEAD(running_trace_list);
-static __cacheline_aligned_in_smp DEFINE_SPINLOCK(running_trace_lock);
+static __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(running_trace_lock);
/* Select an alternative, minimalistic output than the original one */
#define TRACE_BLK_OPT_CLASSIC 0x1
@@ -121,12 +121,12 @@ static void trace_note_tsk(struct task_struct *tsk)
struct blk_trace *bt;
tsk->btrace_seq = blktrace_seq;
- spin_lock_irqsave(&running_trace_lock, flags);
+ raw_spin_lock_irqsave(&running_trace_lock, flags);
list_for_each_entry(bt, &running_trace_list, running_list) {
trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm,
sizeof(tsk->comm), 0);
}
- spin_unlock_irqrestore(&running_trace_lock, flags);
+ raw_spin_unlock_irqrestore(&running_trace_lock, flags);
}
static void trace_note_time(struct blk_trace *bt)
@@ -669,9 +669,9 @@ static int __blk_trace_startstop(struct request_queue *q, int start)
blktrace_seq++;
smp_mb();
bt->trace_state = Blktrace_running;
- spin_lock_irq(&running_trace_lock);
+ raw_spin_lock_irq(&running_trace_lock);
list_add(&bt->running_list, &running_trace_list);
- spin_unlock_irq(&running_trace_lock);
+ raw_spin_unlock_irq(&running_trace_lock);
trace_note_time(bt);
ret = 0;
@@ -679,9 +679,9 @@ static int __blk_trace_startstop(struct request_queue *q, int start)
} else {
if (bt->trace_state == Blktrace_running) {
bt->trace_state = Blktrace_stopped;
- spin_lock_irq(&running_trace_lock);
+ raw_spin_lock_irq(&running_trace_lock);
list_del_init(&bt->running_list);
- spin_unlock_irq(&running_trace_lock);
+ raw_spin_unlock_irq(&running_trace_lock);
relay_flush(bt->rchan);
ret = 0;
}
--
2.28.0
