hw/ppc/spapr_tpm_proxy: skip automatic zero-init of large arrays

The 'tpm_execute' method has a pair of 4k arrays used for copying
data between guest and host. Skip the automatic zero-init of these
arrays to eliminate the performance overhead in the I/O hot path.

The two arrays will be fully initialized when reading data from
guest memory or reading data from the proxy FD.

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: 20250610123709.835102-26-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2025-06-10 13:37:03 +01:00 committed by Stefan Hajnoczi
parent 3438eabaf4
commit 5dd9087fff

View file

@ -41,8 +41,8 @@ static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args)
target_ulong data_in_size = args[2];
uint64_t data_out = ppc64_phys_to_real(args[3]);
target_ulong data_out_size = args[4];
uint8_t buf_in[TPM_SPAPR_BUFSIZE];
uint8_t buf_out[TPM_SPAPR_BUFSIZE];
QEMU_UNINITIALIZED uint8_t buf_in[TPM_SPAPR_BUFSIZE];
QEMU_UNINITIALIZED uint8_t buf_out[TPM_SPAPR_BUFSIZE];
ssize_t ret;
trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size);