dmaengine: at_hdmac: Switch atomic allocations to GFP_NOWAIT (247b4d83) · Commits · 戴 / test

Avoids sleeping without depleting the emergency pool. The rationale being that in most cases a dma device is either offloading an operation that will automatically fallback to software when the descriptor allocation fails, or we can simply poll and wait for the dma device to release some in use descriptors. Signed-off-by:

Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by:

Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-5-tudor.ambarus@microchip.com Signed-off-by:

Vinod Koul <vkoul@kernel.org>

drivers/dma/at_hdmac.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -147,7 +147,7 @@ static struct at_desc atc_desc_get(struct at_dma_chan atchan)

		/* no more descriptor available in initial pool: create one more */
		if (!ret)
		ret = atc_alloc_descriptor(&atchan->chan_common, GFP_ATOMIC);
		ret = atc_alloc_descriptor(&atchan->chan_common, GFP_NOWAIT);

		return ret;
		}
		@@ -931,7 +931,7 @@ atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
		return NULL;
		}

		vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, &paddr);
		vaddr = dma_pool_alloc(atdma->memset_pool, GFP_NOWAIT, &paddr);
		if (!vaddr) {
		dev_err(chan2dev(chan), "%s: couldn't allocate buffer\n",
		__func__);
		@@ -989,7 +989,7 @@ atc_prep_dma_memset_sg(struct dma_chan *chan,
		return NULL;
		}

		vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, &paddr);
		vaddr = dma_pool_alloc(atdma->memset_pool, GFP_NOWAIT, &paddr);
		if (!vaddr) {
		dev_err(chan2dev(chan), "%s: couldn't allocate buffer\n",
		__func__);

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