Re: [PATCH V2 2/2] scsi: implement .cleanup_rq callback

[Bart Van Assche]

On 7/19/19 8:06 PM, Ming Lei wrote:
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index e1da8c70a266..52537c145762 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -154,12 +154,9 @@ scsi_set_blocked(struct scsi_cmnd *cmd, int reason)
  
  static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd)
  {
-       if (cmd->request->rq_flags & RQF_DONTPREP) {
-               cmd->request->rq_flags &= ~RQF_DONTPREP;
-               scsi_mq_uninit_cmd(cmd);
-       } else {
-               WARN_ON_ONCE(true);
-       }
+       WARN_ON_ONCE(!(cmd->request->rq_flags & RQF_DONTPREP));
+
+       scsi_mq_uninit_cmd(cmd);
        blk_mq_requeue_request(cmd->request, true);
  }

The above changes are independent of this patch series. Have you 
considered to move these into a separate patch?

+/*
+ * Only called when the request isn't completed by SCSI, and not freed by
+ * SCSI
+ */
+static void scsi_cleanup_rq(struct request *rq)
+{
+       struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
+
+       scsi_mq_uninit_cmd(cmd);
+}

Is the comment above this function correct? The previous patch adds an 
unconditional call to mq_ops->cleanup_rq() in blk_mq_free_request().

Thanks,

Bart.