[Qemu-devel] [PATCH] hw/dma: Print error message only once

[Philipp Hahn]

otherwise the message
        dma: unregistered DMA channel used nchan=0 dma_pos=0 dma_len=1
gets printed every time and fills up the log-file with 50 MiB / minute.

Signed-off-by: Philipp Hahn <h...@univention.de>
---
 hw/dma/i8257.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/hw/dma/i8257.c b/hw/dma/i8257.c
index dd370ed..9673ab6 100644
--- a/hw/dma/i8257.c
+++ b/hw/dma/i8257.c
@@ -473,8 +473,14 @@ static void dma_reset(void *opaque)
 
 static int dma_phony_handler (void *opaque, int nchan, int dma_pos, int 
dma_len)
 {
-    dolog ("unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d\n",
-           nchan, dma_pos, dma_len);
+    static int once;
+    int mask = 1 << nchan;
+
+    if (0 == (once & mask)) {
+        once |= mask;
+        dolog("unregistered DMA channel used nchan=%d dma_pos=%d dma_len=%d\n",
+              nchan, dma_pos, dma_len);
+    }
     return dma_pos;
 }
 
-- 
1.9.1