net: Avoid extra wakeups of threads blocked in wait_for_packet()

[safe/jmp/linux-2.6] / include / linux / eventfd.h

diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index 0d6ecc6..f45a8ae 100644 (file)
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -8,10 +8,24 @@
 #ifndef _LINUX_EVENTFD_H
 #define _LINUX_EVENTFD_H
 
+#ifdef CONFIG_EVENTFD
 
-#ifdef __KERNEL__
+/* For O_CLOEXEC and O_NONBLOCK */
+#include <linux/fcntl.h>
 
-#ifdef CONFIG_EVENTFD
+/*
+ * CAREFUL: Check include/asm-generic/fcntl.h when defining
+ * new flags, since they might collide with O_* ones. We want
+ * to re-use O_* flags that couldn't possibly have a meaning
+ * from eventfd, in order to leave a free define-space for
+ * shared O_* flags.
+ */
+#define EFD_SEMAPHORE (1 << 0)
+#define EFD_CLOEXEC O_CLOEXEC
+#define EFD_NONBLOCK O_NONBLOCK
+
+#define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
+#define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
 
 struct file *eventfd_fget(int fd);
 int eventfd_signal(struct file *file, int n);
@@ -19,11 +33,10 @@ int eventfd_signal(struct file *file, int n);
 #else /* CONFIG_EVENTFD */
 
 #define eventfd_fget(fd) ERR_PTR(-ENOSYS)
-#define eventfd_signal(f, n) 0
+static inline int eventfd_signal(struct file *file, int n)
+{ return 0; }
 
 #endif /* CONFIG_EVENTFD */
 
-#endif /* __KERNEL__ */
-
 #endif /* _LINUX_EVENTFD_H */