[PATCH 2/3] firewire: core: check precondition when scheduling error callbacks

[Takashi Sakamoto]

Current implementation requires that the transaction not be on the
pending list before its error callback is scheduled. A WARN_ON() in the
callback function detects violations of this precondition, but the check
belongs in the scheduling helper.

Move the WARN_ON() to schedule_error_callback().

Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>
---
 drivers/firewire/core-transaction.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/firewire/core-transaction.c b/drivers/firewire/core-transaction.c
index 31cc440d4218..33f3f272e99b 100644
--- a/drivers/firewire/core-transaction.c
+++ b/drivers/firewire/core-transaction.c
@@ -84,8 +84,14 @@ static void invoke_callback(struct fw_transaction *t, int rcode, u32 response_ts
 	__t;								\
 })
 
+// Ensure that the transaction is not on the pending list when scheduling this work. Cancelling
+// the work after scheduling makes no sense, as the initiator must be notified of the transaction
+// result.
 static void schedule_error_callback(struct fw_transaction *t, int rcode, u32 response_timestamp)
 {
+	// To detect programming mistakes.
+	WARN_ON(!list_empty(&t->link));
+
 	t->rcode = rcode;
 	t->response_timestamp = response_timestamp;
 
@@ -153,16 +159,10 @@ __must_not_hold(&card->transactions.lock)
 }
 EXPORT_SYMBOL(fw_cancel_transaction);
 
-// Ensure that the transaction is not on the pending list when scheduling this work. Cancelling
-// the work after scheduling makes no sense, as the initiator must be notified of the transaction
-// result.
 static void error_callback_work(struct work_struct *work)
 {
 	struct fw_transaction *t = from_work(t, work, error_work);
 
-	// To detect programming mistakes.
-	WARN_ON(!list_empty(&t->link));
-
 	invoke_callback(t, t->rcode, t->response_timestamp, NULL, 0);
 }
 
-- 
2.53.0