summary refs log tree commit diff stats
diff options
context:
space:
mode:
authorDaniel P. Berrangé <berrange@redhat.com>2025-06-10 13:36:53 +0100
committerStefan Hajnoczi <stefanha@redhat.com>2025-06-12 13:40:15 -0400
commitce14f24611aa0469b464a9512e192b4fd51dca2b (patch)
tree05bec02e104d284a14a9c09d7867e87296667405
parent8b1dac1ad57082611419b0e2f347acd96115d25f (diff)
downloadfocaccia-qemu-ce14f24611aa0469b464a9512e192b4fd51dca2b.tar.gz
focaccia-qemu-ce14f24611aa0469b464a9512e192b4fd51dca2b.zip
hw/dma/xlnx_csu_dma: skip automatic zero-init of large array
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>
-rw-r--r--hw/dma/xlnx_csu_dma.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/hw/dma/xlnx_csu_dma.c b/hw/dma/xlnx_csu_dma.c
index 3db3904d83..d8c7da1a50 100644
--- a/hw/dma/xlnx_csu_dma.c
+++ b/hw/dma/xlnx_csu_dma.c
@@ -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);