Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751461AbdGZFhp (ORCPT ); Wed, 26 Jul 2017 01:37:45 -0400 Received: from mail-wm0-f48.google.com ([74.125.82.48]:38430 "EHLO mail-wm0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750884AbdGZFhm (ORCPT ); Wed, 26 Jul 2017 01:37:42 -0400 From: Anup Patel To: Rob Herring , Mark Rutland , Vinod Koul , Dan Williams Cc: Florian Fainelli , Scott Branden , Ray Jui , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, dmaengine@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, Anup Patel Subject: [PATCH 2/6] dma: bcm-sba-raid: Peek mbox when we are left with no free requests Date: Wed, 26 Jul 2017 11:06:40 +0530 Message-Id: <1501047404-14456-3-git-send-email-anup.patel@broadcom.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1501047404-14456-1-git-send-email-anup.patel@broadcom.com> References: <1501047404-14456-1-git-send-email-anup.patel@broadcom.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2041 Lines: 70 We should peek mbox channels when we are left with no free sba_requests in sba_alloc_request() Signed-off-by: Anup Patel Reviewed-by: Ray Jui Reviewed-by: Scott Branden --- drivers/dma/bcm-sba-raid.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c index 6d15fed..321420b 100644 --- a/drivers/dma/bcm-sba-raid.c +++ b/drivers/dma/bcm-sba-raid.c @@ -199,6 +199,14 @@ static inline u32 __pure sba_cmd_pq_c_mdata(u32 d, u32 b1, u32 b0) /* ====== General helper routines ===== */ +static void sba_peek_mchans(struct sba_device *sba) +{ + int mchan_idx; + + for (mchan_idx = 0; mchan_idx < sba->mchans_count; mchan_idx++) + mbox_client_peek_data(sba->mchans[mchan_idx]); +} + static struct sba_request *sba_alloc_request(struct sba_device *sba) { unsigned long flags; @@ -210,8 +218,17 @@ static struct sba_request *sba_alloc_request(struct sba_device *sba) if (req) list_move_tail(&req->node, &sba->reqs_alloc_list); spin_unlock_irqrestore(&sba->reqs_lock, flags); - if (!req) + + if (!req) { + /* + * We have no more free requests so, we peek + * mailbox channels hoping few active requests + * would have completed which will create more + * room for new requests. + */ + sba_peek_mchans(sba); return NULL; + } req->flags = SBA_REQUEST_STATE_ALLOCED; req->first = req; @@ -558,17 +575,15 @@ static enum dma_status sba_tx_status(struct dma_chan *dchan, dma_cookie_t cookie, struct dma_tx_state *txstate) { - int mchan_idx; enum dma_status ret; struct sba_device *sba = to_sba_device(dchan); - for (mchan_idx = 0; mchan_idx < sba->mchans_count; mchan_idx++) - mbox_client_peek_data(sba->mchans[mchan_idx]); - ret = dma_cookie_status(dchan, cookie, txstate); if (ret == DMA_COMPLETE) return ret; + sba_peek_mchans(sba); + return dma_cookie_status(dchan, cookie, txstate); } -- 2.7.4