iwlwifi: allow rate-limited error messages

Sometimes we might want to have an error message for something
related to TX/RX, but if that somehow happens frequently it'll
overwhelm the logs. Add IWL_ERR_LIMIT() to alleviate that by
rate-limiting those messages.

To do this, rework __iwl_err() a bit to have a mode argument
instead of passing yet another (bool) argument to it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20211017162352.2cb1e6b75672.Iec5b1c1bcc6ebc87c586921a6c5c2a937f49e83c@changeidSigned-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/dvm/agn.h

 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
 /*
- * Copyright (C) 2005-2014 Intel Corporation
+ * Copyright (C) 2005-2014, 2021 Intel Corporation
  */
 #ifndef __iwl_agn_h__
 #define __iwl_agn_h__
@@ -398,8 +398,10 @@ do {									\
 	if (!iwl_is_rfkill((m)))					\
 		IWL_ERR(m, fmt, ##args);				\
 	else								\
-		__iwl_err((m)->dev, true,				\
-			  !iwl_have_debug_level(IWL_DL_RADIO),		\
+		__iwl_err((m)->dev,					\
+			  iwl_have_debug_level(IWL_DL_RADIO) ?		\
+				IWL_ERR_MODE_RFKILL :			\
+				IWL_ERR_MODE_TRACE_ONLY,		\
 			  fmt, ##args);					\
 } while (0)
 #else
@@ -408,7 +410,8 @@ do {									\
 	if (!iwl_is_rfkill((m)))					\
 		IWL_ERR(m, fmt, ##args);				\
 	else								\
-		__iwl_err((m)->dev, true, true, fmt, ##args);	\
+		__iwl_err((m)->dev, IWL_ERR_MODE_TRACE_ONLY,		\
+			  fmt, ##args);					\
 } while (0)
 #endif				/* CONFIG_IWLWIFI_DEBUG */
 

drivers/net/wireless/intel/iwlwifi/iwl-debug.c

 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
 /*
- * Copyright (C) 2005-2011 Intel Corporation
+ * Copyright (C) 2005-2011, 2021 Intel Corporation
  */
 #include <linux/device.h>
 #include <linux/interrupt.h>
@@ -31,21 +31,31 @@ IWL_EXPORT_SYMBOL(__iwl_info);
 __iwl_fn(crit)
 IWL_EXPORT_SYMBOL(__iwl_crit);
 
-void __iwl_err(struct device *dev, bool rfkill_prefix, bool trace_only,
-		const char *fmt, ...)
+void __iwl_err(struct device *dev, enum iwl_err_mode mode, const char *fmt, ...)
 {
 	struct va_format vaf = {
 		.fmt = fmt,
 	};
-	va_list args;
+	va_list args, args2;
 
 	va_start(args, fmt);
-	vaf.va = &args;
-	if (!trace_only) {
-		if (rfkill_prefix)
+	switch (mode) {
+	case IWL_ERR_MODE_RATELIMIT:
+		if (net_ratelimit())
+			break;
+		fallthrough;
+	case IWL_ERR_MODE_REGULAR:
+	case IWL_ERR_MODE_RFKILL:
+		va_copy(args2, args);
+		vaf.va = &args2;
+		if (mode == IWL_ERR_MODE_RFKILL)
 			dev_err(dev, "(RFKILL) %pV", &vaf);
 		else
 			dev_err(dev, "%pV", &vaf);
+		va_end(args2);
+		break;
+	default:
+		break;
 	}
 	trace_iwlwifi_err(&vaf);
 	va_end(args);

drivers/net/wireless/intel/iwlwifi/iwl-debug.h

@@ -2,7 +2,7 @@
 /******************************************************************************
  *
  * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved.
- * Copyright(c) 2018 - 2020 Intel Corporation
+ * Copyright(c) 2018 - 2021 Intel Corporation
  *
  * Portions of this file are derived from the ipw3945 project.
  *****************************************************************************/
@@ -22,9 +22,16 @@ static inline bool iwl_have_debug_level(u32 level)
 #endif
 }
 
+enum iwl_err_mode {
+	IWL_ERR_MODE_REGULAR,
+	IWL_ERR_MODE_RFKILL,
+	IWL_ERR_MODE_TRACE_ONLY,
+	IWL_ERR_MODE_RATELIMIT,
+};
+
 struct device;
-void __iwl_err(struct device *dev, bool rfkill_prefix, bool only_trace,
-		const char *fmt, ...) __printf(4, 5);
+void __iwl_err(struct device *dev, enum iwl_err_mode mode, const char *fmt, ...)
+	__printf(3, 4);
 void __iwl_warn(struct device *dev, const char *fmt, ...) __printf(2, 3);
 void __iwl_info(struct device *dev, const char *fmt, ...) __printf(2, 3);
 void __iwl_crit(struct device *dev, const char *fmt, ...) __printf(2, 3);
@@ -33,13 +40,17 @@ void __iwl_crit(struct device *dev, const char *fmt, ...) __printf(2, 3);
 #define CHECK_FOR_NEWLINE(f) BUILD_BUG_ON(f[sizeof(f) - 2] != '\n')
 
 /* No matter what is m (priv, bus, trans), this will work */
-#define IWL_ERR_DEV(d, f, a...)						\
+#define __IWL_ERR_DEV(d, mode, f, a...)					\
 	do {								\
 		CHECK_FOR_NEWLINE(f);					\
-		__iwl_err((d), false, false, f, ## a);			\
+		__iwl_err((d), mode, f, ## a);				\
 	} while (0)
+#define IWL_ERR_DEV(d, f, a...)						\
+	__IWL_ERR_DEV(d, IWL_ERR_MODE_REGULAR, f, ## a)
 #define IWL_ERR(m, f, a...)						\
 	IWL_ERR_DEV((m)->dev, f, ## a)
+#define IWL_ERR_LIMIT(m, f, a...)					\
+	__IWL_ERR_DEV((m)->dev, IWL_ERR_MODE_RATELIMIT, f, ## a)
 #define IWL_WARN(m, f, a...)						\
 	do {								\
 		CHECK_FOR_NEWLINE(f);					\