hw/ppc/pnv_occ: skip automatic zero-init of large struct

The 'occ_model_tick' method has a 12k struct used for copying
data between guest and host. Skip the automatic zero-init of this
struct to eliminate the performance overhead in the I/O hot path.

The 'dynamic_data' buffer will be fully initialized when reading
data from the guest.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-id: 20250610123709.835102-25-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2025-06-10 13:37:02 +01:00 committed by Stefan Hajnoczi
parent 7eeb1d3acc
commit 3438eabaf4

View file

@ -789,7 +789,7 @@ static bool occ_opal_process_command(PnvOCC *occ,
static bool occ_model_tick(PnvOCC *occ)
{
struct occ_dynamic_data dynamic_data;
QEMU_UNINITIALIZED struct occ_dynamic_data dynamic_data;
if (!occ_read_dynamic_data(occ, &dynamic_data, NULL)) {
/* Can't move OCC state field to safe because we can't map it! */