qcacmn: Rate limit logs based on elapsed time

QDF_TRACE_RATE_LIMITED() currently rate limits by only printing every
rate'th call to the function from the same location. Instead, prevent
logging messages more than some constant 'k' times per second. This
means any subsequent calls to the API from the same location within 1/k
seconds will be dropped.

Change-Id: I31a3f48f68fb6bc67f59f3157a635345943d3331
CRs-Fixed: 2205794

qdf/linux/src/i_qdf_trace.h

@@ -58,14 +58,26 @@
 #define QDF_TRACE qdf_trace_msg
 #define QDF_VTRACE qdf_vtrace_msg
 #define QDF_TRACE_HEX_DUMP qdf_trace_hex_dump
-#define QDF_TRACE_RATE_LIMITED(rate, module, level, format, ...)\
+#define QDF_MAX_LOGS_PER_SEC 2
+/**
+ * QDF_TRACE_RATE_LIMITED() - rate limited version of QDF_TRACE
+ * @params: parameters to pass through to QDF_TRACE
+ *
+ * This API prevents logging a message more than QDF_MAX_LOGS_PER_SEC times per
+ * second. This means any subsequent calls to this API from the same location
+ * within 1/QDF_MAX_LOGS_PER_SEC seconds will be dropped.
+ *
+ * Return: None
+ */
+#define QDF_TRACE_RATE_LIMITED(params...)\
 	do {\
-		static int rate_limit;\
-		rate_limit++;\
-		if (rate)\
-			if (0 == (rate_limit % rate))\
-				qdf_trace_msg(module, level, format,\
-						##__VA_ARGS__);\
+		static ulong __last_ticks;\
+		ulong __ticks = jiffies;\
+		if (time_after(__ticks,\
+			       __last_ticks + HZ / QDF_MAX_LOGS_PER_SEC)) {\
+			QDF_TRACE(params);\
+			__last_ticks = __ticks;\
+		} \
 	} while (0)
 #else
 #define QDF_TRACE(arg ...)