[PATCH v3 06/12] dmaengine: at_xdmac: Move the free desc to the tail of the desc list
From: Tudor Ambarus <hidden>
Date: 2021-12-15 11:01:48
Also in:
dmaengine, lkml
Subsystem:
dma generic offload engine subsystem, microchip at91 dma drivers, the rest · Maintainers:
Vinod Koul, Ludovic Desroches, Linus Torvalds
Move the free desc to the tail of the list, so that the sequence of descriptors is more track-able in case of debug. One would know which descriptor should come next and could easier catch concurrency over descriptors for example. virt-dma uses list_splice_tail_init() as well, follow the core driver. Signed-off-by: Tudor Ambarus <redacted> --- drivers/dma/at_xdmac.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
index d5b37459f906..b6547f1b5645 100644
--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c@@ -729,7 +729,8 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) - list_splice_init(&first->descs_list, &atchan->free_descs_list); + list_splice_tail_init(&first->descs_list, + &atchan->free_descs_list); goto spin_unlock; }
@@ -817,7 +818,8 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) - list_splice_init(&first->descs_list, &atchan->free_descs_list); + list_splice_tail_init(&first->descs_list, + &atchan->free_descs_list); spin_unlock_irqrestore(&atchan->lock, irqflags); return NULL; }
@@ -1051,8 +1053,8 @@ at_xdmac_prep_interleaved(struct dma_chan *chan, src_addr, dst_addr, xt, chunk); if (!desc) { - list_splice_init(&first->descs_list, - &atchan->free_descs_list); + list_splice_tail_init(&first->descs_list, + &atchan->free_descs_list); return NULL; }
@@ -1132,7 +1134,8 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) - list_splice_init(&first->descs_list, &atchan->free_descs_list); + list_splice_tail_init(&first->descs_list, + &atchan->free_descs_list); return NULL; }
@@ -1308,8 +1311,8 @@ at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl, sg_dma_len(sg), value); if (!desc && first) - list_splice_init(&first->descs_list, - &atchan->free_descs_list); + list_splice_tail_init(&first->descs_list, + &atchan->free_descs_list); if (!first) first = desc;
@@ -1701,7 +1704,8 @@ static void at_xdmac_tasklet(struct tasklet_struct *t) spin_lock_irq(&atchan->lock); /* Move the xfer descriptors into the free descriptors list. */ - list_splice_init(&desc->descs_list, &atchan->free_descs_list); + list_splice_tail_init(&desc->descs_list, + &atchan->free_descs_list); at_xdmac_advance_work(atchan); spin_unlock_irq(&atchan->lock); }
@@ -1850,7 +1854,8 @@ static int at_xdmac_device_terminate_all(struct dma_chan *chan) /* Cancel all pending transfers. */ list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) { list_del(&desc->xfer_node); - list_splice_init(&desc->descs_list, &atchan->free_descs_list); + list_splice_tail_init(&desc->descs_list, + &atchan->free_descs_list); } clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
--
2.25.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel