[SCSI] bnx2fc: IO completion not processed due to missed wakeup
Driver does not detect a new CQE (completion queue entry) if a thread receives
the wakup when it is in TASK_RUNNING state. Fix is to set the state to
TASK_INTERRUPTIBLE while holding the fp_work_lock.
Also, Use __set_current_task() since it is now set inside a spinlock with
synchronization.
Two other related optimizations:
1. After we exit the while (!kthread_should_stop()) loop, use
__set_current_state() since synchronization is no longer needed.
2. Remove set_current_state(TASK_RUNNING) after schedule() since it
should always be TASK_RUNNING after schedule().
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index 2056890..e2e6475 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -437,17 +437,16 @@
set_current_state(TASK_INTERRUPTIBLE);
while (!kthread_should_stop()) {
schedule();
- set_current_state(TASK_RUNNING);
spin_lock_bh(&bg->fcoe_rx_list.lock);
while ((skb = __skb_dequeue(&bg->fcoe_rx_list)) != NULL) {
spin_unlock_bh(&bg->fcoe_rx_list.lock);
bnx2fc_recv_frame(skb);
spin_lock_bh(&bg->fcoe_rx_list.lock);
}
+ __set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_bh(&bg->fcoe_rx_list.lock);
- set_current_state(TASK_INTERRUPTIBLE);
}
- set_current_state(TASK_RUNNING);
+ __set_current_state(TASK_RUNNING);
return 0;
}
@@ -569,7 +568,6 @@
set_current_state(TASK_INTERRUPTIBLE);
while (!kthread_should_stop()) {
schedule();
- set_current_state(TASK_RUNNING);
spin_lock_bh(&p->fp_work_lock);
while (!list_empty(&p->work_list)) {
list_splice_init(&p->work_list, &work_list);
@@ -583,10 +581,10 @@
spin_lock_bh(&p->fp_work_lock);
}
+ __set_current_state(TASK_INTERRUPTIBLE);
spin_unlock_bh(&p->fp_work_lock);
- set_current_state(TASK_INTERRUPTIBLE);
}
- set_current_state(TASK_RUNNING);
+ __set_current_state(TASK_RUNNING);
return 0;
}