motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-03 15:53:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

hw/dma/xlnx_csu_dma: skip automatic zero-init of large array

Browse source 
The 'xlnx_csu_dma_src_notify' method has a 4k byte array used for
copying DMA data. Skip the automatic zero-init of this array to
eliminate the performance overhead in the I/O hot path.

The 'buf' array will be fully initialized when data is copied.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20250610123709.835102-16-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2025-06-10 13:36:53 +01:00 • committed by Stefan Hajnoczi
parent 8b1dac1ad5
commit ce14f24611
1 changed files with 1 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
hw/dma/xlnx_csu_dma.c
View file

@ -287,7 +287,7 @@ static uint32_t xlnx_csu_dma_advance(XlnxCSUDMA *s, uint32_t len)
static void xlnx_csu_dma_src_notify(void *opaque)
{
XlnxCSUDMA *s = XLNX_CSU_DMA(opaque);
unsigned char buf[4 * 1024];
QEMU_UNINITIALIZED unsigned char buf[4 * 1024];
size_t rlen = 0;
ptimer_transaction_begin(s->src_timer);