ioatdma: Push pending transactions to hardware more frequently

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]>
josf · Jul 11, 2007 · 000725d · 000725d
1 parent 7dcca30
commit 000725d
Showing 1 changed file with 2 additions and 2 deletions.
diff --git 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");