bug.h: Add WARN_RATELIMIT

[ Upstream commit b3eec79b0776e5340a3db75b34953977c7e5086e ]

Add a generic mechanism to ratelimit WARN(foo, fmt, ...) messages
using a hidden per call site static struct ratelimit_state.

Also add an __WARN_RATELIMIT variant to be able to use a specific
struct ratelimit_state.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>

diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index c2c9ba032d4688c80cf7b3e1546da8a558068ec5..205e167804c4999629f25373fa6a1ae81d53f71f 100644 (file)
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -53,6 +53,22 @@ struct bug_entry {
 #define BUG_ON(condition) do { if (unlikely(condition)) BUG(); } while(0)
 #endif
 
+#define __WARN_RATELIMIT(condition, state, format...)          \
+({                                                             \
+       int rtn = 0;                                            \
+       if (unlikely(__ratelimit(state)))                       \
+               rtn = WARN(condition, format);                  \
+       rtn;                                                    \
+})
+
+#define WARN_RATELIMIT(condition, format...)                   \
+({                                                             \
+       static DEFINE_RATELIMIT_STATE(_rs,                      \
+                                     DEFAULT_RATELIMIT_INTERVAL,       \
+                                     DEFAULT_RATELIMIT_BURST); \
+       __WARN_RATELIMIT(condition, &_rs, format);              \
+})
+
 /*
  * WARN(), WARN_ON(), WARN_ON_ONCE, and so on can be used to report
  * significant issues that need prompt attention if they should ever