[PATCH v2 02/16] dmaengine: bcm-sba-raid: Reduce locking context in sba_alloc_request()

[Anup Patel]

We don't require to hold "sba->reqs_lock" for long-time
in sba_alloc_request() because lock protection is not
required when initializing members of "struct sba_request".

Signed-off-by: Anup Patel <anup.pa...@broadcom.com>
---
 drivers/dma/bcm-sba-raid.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c
index 76999b7..f81d5ac 100644
--- a/drivers/dma/bcm-sba-raid.c
+++ b/drivers/dma/bcm-sba-raid.c
@@ -207,24 +207,24 @@ static struct sba_request *sba_alloc_request(struct 
sba_device *sba)
        struct sba_request *req = NULL;
 
        spin_lock_irqsave(&sba->reqs_lock, flags);
-
        req = list_first_entry_or_null(&sba->reqs_free_list,
                                       struct sba_request, node);
        if (req) {
                list_move_tail(&req->node, &sba->reqs_alloc_list);
-               req->state = SBA_REQUEST_STATE_ALLOCED;
-               req->fence = false;
-               req->first = req;
-               INIT_LIST_HEAD(&req->next);
-               req->next_count = 1;
-               atomic_set(&req->next_pending_count, 1);
-
                sba->reqs_free_count--;
-
-               dma_async_tx_descriptor_init(&req->tx, &sba->dma_chan);
        }
-
        spin_unlock_irqrestore(&sba->reqs_lock, flags);
+       if (!req)
+               return NULL;
+
+       req->state = SBA_REQUEST_STATE_ALLOCED;
+       req->fence = false;
+       req->first = req;
+       INIT_LIST_HEAD(&req->next);
+       req->next_count = 1;
+       atomic_set(&req->next_pending_count, 1);
+
+       dma_async_tx_descriptor_init(&req->tx, &sba->dma_chan);
 
        return req;
 }
-- 
2.7.4