You can now write code like this:
FLOOD_COUNTER(errcount, 100);
...
NO_FLOOD(errcount,
error_report("oops, something bad happened"),
error_report("further errors suppressed"));
which would print the "oops, ..." error message up to 100 times,
followed by the "further errors suppressed" message once, and then
nothing else.
Signed-off-by: Richard W.M. Jones <rjo...@redhat.com>
---
include/qemu/no-flood.h | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
create mode 100644 include/qemu/no-flood.h
diff --git a/include/qemu/no-flood.h b/include/qemu/no-flood.h
new file mode 100644
index 0000000..90a24da
--- /dev/null
+++ b/include/qemu/no-flood.h
@@ -0,0 +1,34 @@
+/*
+ * Suppress error floods.
+ *
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * Author: Richard W.M. Jones <rjo...@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef __QEMU_NO_FLOOD_H
+#define __QEMU_NO_FLOOD_H 1
+
+#include "qemu/atomic.h"
+
+/* Suggested initial value is 100 */
+#define FLOOD_COUNTER(counter_name, initial) \
+ static int counter_name = (initial)
+
+#define NO_FLOOD(counter_name, code, suppress_message) \
+ do { \
+ int t_##counter_name = atomic_fetch_add(&counter_name, 0); \
+ if (t_##counter_name > 0) { \
+ code; \
+ if (t_##counter_name == 1) { \
+ suppress_message; \
+ } \
+ atomic_dec(&counter_name); \
+ } \
+} while (0)
+
+#endif
--
2.3.1
