patch-2.1.36 linux/include/asm-sparc64/spinlock.h

• Lines: 41
• Date: Tue Apr 22 22:39:21 1997
• Orig file: v2.1.35/linux/include/asm-sparc64/spinlock.h
• Orig date: Mon Apr 14 16:28:24 1997

diff -u --recursive --new-file v2.1.35/linux/include/asm-sparc64/spinlock.h linux/include/asm-sparc64/spinlock.h
@@ -16,12 +16,40 @@
 #define spin_lock_init(lock)	do { } while(0)
 #define spin_lock(lock)		do { } while(0)
 #define spin_trylock(lock)	do { } while(0)
+#define spin_unlock_wait(lock)	do { } while(0)
 #define spin_unlock(lock)	do { } while(0)
 #define spin_lock_irq(lock)	cli()
 #define spin_unlock_irq(lock)	sti()
 
 #define spin_lock_irqsave(lock, flags)		save_and_cli(flags)
 #define spin_unlock_irqrestore(lock, flags)	restore_flags(flags)
+
+/*
+ * Read-write spinlocks, allowing multiple readers
+ * but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts
+ * but no interrupt writers. For those circumstances we
+ * can "mix" irq-safe locks - any writer needs to get a
+ * irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ */
+typedef struct { } rwlock_t;
+#define RW_LOCK_UNLOCKED { }
+
+#define read_lock(lock)		do { } while(0)
+#define read_unlock(lock)	do { } while(0)
+#define write_lock(lock)	do { } while(0)
+#define write_unlock(lock)	do { } while(0)
+#define read_lock_irq(lock)	cli()
+#define read_unlock_irq(lock)	sti()
+#define write_lock_irq(lock)	cli()
+#define write_unlock_irq(lock)	sti()
+
+#define read_lock_irqsave(lock, flags)		save_and_cli(flags)
+#define read_unlock_irqrestore(lock, flags)	restore_flags(flags)
+#define write_lock_irqsave(lock, flags)		save_and_cli(flags)
+#define write_unlock_irqrestore(lock, flags)	restore_flags(flags)
 
 #else /* !(__SMP__) */
 #error SMP not supported on sparc64