diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/bcm-sba-raid.c | 109 |
1 files changed, 47 insertions, 62 deletions
diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c index cb48d98e853e..abed03967e94 100644 --- a/drivers/dma/bcm-sba-raid.c +++ b/drivers/dma/bcm-sba-raid.c @@ -419,22 +419,20 @@ static int sba_send_mbox_request(struct sba_device *sba, return 0; } -static void sba_process_deferred_requests(struct sba_device *sba) +/* Note: Must be called with sba->reqs_lock held */ +static void _sba_process_pending_requests(struct sba_device *sba) { int ret; u32 count; - unsigned long flags; struct sba_request *req; - struct dma_async_tx_descriptor *tx; - - spin_lock_irqsave(&sba->reqs_lock, flags); - - /* Count pending requests */ - count = 0; - list_for_each_entry(req, &sba->reqs_pending_list, node) - count++; - /* Process pending requests */ + /* + * Process few pending requests + * + * For now, we process (<number_of_mailbox_channels> * 8) + * number of requests at a time. + */ + count = sba->mchans_count * 8; while (!list_empty(&sba->reqs_pending_list) && count) { /* Get the first pending request */ req = list_first_entry(&sba->reqs_pending_list, @@ -445,11 +443,7 @@ static void sba_process_deferred_requests(struct sba_device *sba) break; /* Send request to mailbox channel */ - spin_unlock_irqrestore(&sba->reqs_lock, flags); ret = sba_send_mbox_request(sba, req); - spin_lock_irqsave(&sba->reqs_lock, flags); - - /* If something went wrong then keep request pending */ if (ret < 0) { _sba_pending_request(sba, req); break; @@ -457,20 +451,18 @@ static void sba_process_deferred_requests(struct sba_device *sba) count--; } +} - /* Count completed requests */ - count = 0; - list_for_each_entry(req, &sba->reqs_completed_list, node) - count++; - - /* Process completed requests */ - while (!list_empty(&sba->reqs_completed_list) && count) { - req = list_first_entry(&sba->reqs_completed_list, - struct sba_request, node); - list_del_init(&req->node); - tx = &req->tx; +static void sba_process_received_request(struct sba_device *sba, + struct sba_request *req) +{ + unsigned long flags; + struct dma_async_tx_descriptor *tx; + struct sba_request *nreq, *first = req->first; - spin_unlock_irqrestore(&sba->reqs_lock, flags); + /* Process only after all chained requests are received */ + if (!atomic_dec_return(&first->next_pending_count)) { + tx = &first->tx; WARN_ON(tx->cookie < 0); if (tx->cookie > 0) { @@ -485,41 +477,34 @@ static void sba_process_deferred_requests(struct sba_device *sba) spin_lock_irqsave(&sba->reqs_lock, flags); - /* If waiting for 'ack' then move to completed list */ - if (!async_tx_test_ack(&req->tx)) - _sba_complete_request(sba, req); - else - _sba_free_request(sba, req); + /* Free all requests chained to first request */ + list_for_each_entry(nreq, &first->next, next) + _sba_free_request(sba, nreq); + INIT_LIST_HEAD(&first->next); - count--; - } + /* Mark request as received */ + _sba_received_request(sba, first); - /* Re-check pending and completed work */ - count = 0; - if (!list_empty(&sba->reqs_pending_list) || - !list_empty(&sba->reqs_completed_list)) - count = 1; - - spin_unlock_irqrestore(&sba->reqs_lock, flags); -} - -static void sba_process_received_request(struct sba_device *sba, - struct sba_request *req) -{ - unsigned long flags; - - spin_lock_irqsave(&sba->reqs_lock, flags); + /* The client is allowed to attach dependent operations + * until 'ack' is set + */ + if (!async_tx_test_ack(tx)) + _sba_complete_request(sba, first); + else + _sba_free_request(sba, first); - /* Mark request as received */ - _sba_received_request(sba, req); + /* Cleanup completed requests */ + list_for_each_entry_safe(req, nreq, + &sba->reqs_completed_list, node) { + if (async_tx_test_ack(&req->tx)) + _sba_free_request(sba, req); + } - /* Update request */ - if (!atomic_dec_return(&req->first->next_pending_count)) - _sba_complete_request(sba, req->first); - if (req->first != req) - _sba_free_request(sba, req); + /* Process pending requests */ + _sba_process_pending_requests(sba); - spin_unlock_irqrestore(&sba->reqs_lock, flags); + spin_unlock_irqrestore(&sba->reqs_lock, flags); + } } /* ====== DMAENGINE callbacks ===== */ @@ -544,10 +529,13 @@ static int sba_device_terminate_all(struct dma_chan *dchan) static void sba_issue_pending(struct dma_chan *dchan) { + unsigned long flags; struct sba_device *sba = to_sba_device(dchan); - /* Process deferred requests */ - sba_process_deferred_requests(sba); + /* Process pending requests */ + spin_lock_irqsave(&sba->reqs_lock, flags); + _sba_process_pending_requests(sba); + spin_unlock_irqrestore(&sba->reqs_lock, flags); } static dma_cookie_t sba_tx_submit(struct dma_async_tx_descriptor *tx) @@ -1482,9 +1470,6 @@ static void sba_receive_message(struct mbox_client *cl, void *msg) /* Process received request */ sba_process_received_request(sba, req); - - /* Process deferred requests */ - sba_process_deferred_requests(sba); } /* ====== Platform driver routines ===== */ |