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hw/audio/gus: skip automatic zero-init of large array

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The 'GUS_read_DMA' method has a 4k byte array used for copying
data between the audio backend and device. Skip the automatic
zero-init of this array to eliminate the performance overhead in
the I/O hot path.

The 'tmpbuf' array will be fully initialized when reading data
from device memory.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20250610123709.835102-11-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2025-06-10 13:36:48 +01:00 • committed by Stefan Hajnoczi
parent 8236e20608
commit 2e438da492
1 changed files with 1 additions and 1 deletions
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2
hw/audio/gus.c
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@ -183,7 +183,7 @@ static int GUS_read_DMA (void *opaque, int nchan, int dma_pos, int dma_len)
{
GUSState *s = opaque;
IsaDmaClass *k = ISADMA_GET_CLASS(s->isa_dma);
char tmpbuf[4096];
QEMU_UNINITIALIZED char tmpbuf[4096];
int pos = dma_pos, mode, left = dma_len - dma_pos;
ldebug ("read DMA %#x %d\n", dma_pos, dma_len);