Every 20 descriptors turns out to be to few append commands with newer/faster CPUs. Pushing every 4 still cuts down on MMIO writes to an acceptable level without letting the DMA engine run out of work.
Signed-off-by: Chris Leech <[EMAIL PROTECTED]> --- drivers/dma/ioatdma.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/ioatdma.c b/drivers/dma/ioatdma.c index 8e87261..0f77a9d 100644 --- a/drivers/dma/ioatdma.c +++ b/drivers/dma/ioatdma.c @@ -310,7 +310,7 @@ static dma_cookie_t do_ioat_dma_memcpy(struct ioat_dma_chan *ioat_chan, list_splice_init(&new_chain, ioat_chan->used_desc.prev); ioat_chan->pending += desc_count; - if (ioat_chan->pending >= 20) { + if (ioat_chan->pending >= 4) { append = 1; ioat_chan->pending = 0; } @@ -818,7 +818,7 @@ static void __devexit ioat_remove(struct pci_dev *pdev) } /* MODULE API */ -MODULE_VERSION("1.7"); +MODULE_VERSION("1.9"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Intel Corporation"); - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html