datapath: add netlink error message to help kernel userspace integration.

[sliver-openvswitch.git] / datapath / linux / compat / include / linux / kernel.h

diff --git a/datapath/linux/compat/include/linux/kernel.h b/datapath/linux/compat/include/linux/kernel.h
index 2fa5cc8..fdd2005 100644 (file)
--- a/datapath/linux/compat/include/linux/kernel.h
+++ b/datapath/linux/compat/include/linux/kernel.h
@@ -39,6 +39,40 @@
 #define pr_warn pr_warning
 #endif
 
+/*
+ * Print a one-time message (analogous to WARN_ONCE() et al):
+ */
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 38)
+#undef printk_once
+#define printk_once(fmt, ...)                  \
+({                                             \
+       static bool __print_once;               \
+                                               \
+       if (!__print_once) {                    \
+               __print_once = true;            \
+               printk(fmt, ##__VA_ARGS__);     \
+       }                                       \
+})
+
+#define pr_emerg_once(fmt, ...)                                        \
+       printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_alert_once(fmt, ...)                                        \
+       printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_crit_once(fmt, ...)                                 \
+       printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_err_once(fmt, ...)                                  \
+       printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_warn_once(fmt, ...)                                 \
+       printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_notice_once(fmt, ...)                               \
+       printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_info_once(fmt, ...)                                 \
+       printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
+#define pr_cont_once(fmt, ...)                                 \
+       printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
+
+#endif
+
 #if defined(CONFIG_PREEMPT) && LINUX_VERSION_CODE < KERNEL_VERSION(2,6,21)
 #error "CONFIG_PREEMPT is broken before 2.6.21--see commit 4498121ca3, \"[NET]: Handle disabled preemption in gfp_any()\""
 #endif