hw/net/tulip: skip automatic zero-init of large array

The 'tulip_setup_frame' method has a 4k byte array used for copynig
DMA data from the device. 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 reading data from the
device.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20250610123709.835102-21-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2025-06-10 13:36:58 +01:00 committed by Stefan Hajnoczi
parent 3ccc6489dd
commit e1afd5ee6e

View file

@ -629,7 +629,7 @@ static void tulip_setup_filter_addr(TULIPState *s, uint8_t *buf, int n)
static void tulip_setup_frame(TULIPState *s,
struct tulip_descriptor *desc)
{
uint8_t buf[4096];
QEMU_UNINITIALIZED uint8_t buf[4096];
int len = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK;
int i;