md/raid5: Move stripe_add_to_batch_list() call out of add_stripe_bio()

stripe_add_to_batch_list() is better done in the loop in make_request
instead of inside add_stripe_bio(). This is clearer and allows for
storing the batch_head state outside the loop in a subsequent patch.

The call to add_stripe_bio() in retry_aligned_read() is for read
and batching only applies to write. So it's impossible for batching
to happen at that call site.

No functional changes intended.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/md/raid5.c

@@ -3532,8 +3532,6 @@ static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx,
 	}
 	spin_unlock_irq(&sh->stripe_lock);
 
-	if (stripe_can_batch(sh))
-		stripe_add_to_batch_list(conf, sh);
 	return 1;
 
  overlap:
@@ -5951,6 +5949,9 @@ static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 			goto retry;
 		}
 
+		if (stripe_can_batch(sh))
+			stripe_add_to_batch_list(conf, sh);
+
 		if (do_flush) {
 			set_bit(STRIPE_R5C_PREFLUSH, &sh->state);
 			/* we only need flush for one stripe */