Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / include / linux / percpu-rwsem.h

diff --git a/kernel/include/linux/percpu-rwsem.h b/kernel/include/linux/percpu-rwsem.h
new file mode 100644 (file)
index 0000000..3e88c9a
--- /dev/null
+++ b/kernel/include/linux/percpu-rwsem.h
@@ -0,0 +1,34 @@
+#ifndef _LINUX_PERCPU_RWSEM_H
+#define _LINUX_PERCPU_RWSEM_H
+
+#include <linux/atomic.h>
+#include <linux/rwsem.h>
+#include <linux/percpu.h>
+#include <linux/wait.h>
+#include <linux/lockdep.h>
+
+struct percpu_rw_semaphore {
+       unsigned int __percpu   *fast_read_ctr;
+       atomic_t                write_ctr;
+       struct rw_semaphore     rw_sem;
+       atomic_t                slow_read_ctr;
+       wait_queue_head_t       write_waitq;
+};
+
+extern void percpu_down_read(struct percpu_rw_semaphore *);
+extern void percpu_up_read(struct percpu_rw_semaphore *);
+
+extern void percpu_down_write(struct percpu_rw_semaphore *);
+extern void percpu_up_write(struct percpu_rw_semaphore *);
+
+extern int __percpu_init_rwsem(struct percpu_rw_semaphore *,
+                               const char *, struct lock_class_key *);
+extern void percpu_free_rwsem(struct percpu_rw_semaphore *);
+
+#define percpu_init_rwsem(brw) \
+({                                                             \
+       static struct lock_class_key rwsem_key;                 \
+       __percpu_init_rwsem(brw, #brw, &rwsem_key);             \
+})
+
+#endif