patch-2.1.30 linux/include/asm-i386/hardirq.h

• Lines: 69
• Date: Wed Mar 26 09:53:06 1997
• Orig file: v2.1.29/linux/include/asm-i386/hardirq.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.29/linux/include/asm-i386/hardirq.h linux/include/asm-i386/hardirq.h
@@ -0,0 +1,68 @@
+#ifndef __ASM_HARDIRQ_H
+#define __ASM_HARDIRQ_H
+
+extern unsigned int local_irq_count[NR_CPUS];
+#define in_interrupt()	(local_irq_count[smp_processor_id()] != 0)
+
+#ifndef __SMP__
+
+#define hardirq_trylock(cpu)	((cpu)==0)	/* always true */
+#define hardirq_endlock(cpu)	do { } while (0)
+
+#define hardirq_enter(cpu)	(local_irq_count[cpu]++)
+#define hardirq_exit(cpu)	(local_irq_count[cpu]--)
+
+#else
+
+extern unsigned char global_irq_holder;
+extern unsigned volatile int global_irq_lock;
+extern unsigned volatile int global_irq_count;
+
+static inline void release_irqlock(int cpu)
+{
+	/* if we didn't own the irq lock, just ignore.. */
+	if (global_irq_holder == (unsigned char) cpu) {
+		global_irq_holder = NO_PROC_ID;
+		global_irq_lock = 0;
+	}
+}
+
+static inline void hardirq_enter(int cpu)
+{
+	++local_irq_count[cpu];
+	atomic_inc(&global_irq_count);
+}
+
+static inline void hardirq_exit(int cpu)
+{
+	atomic_dec(&global_irq_count);
+	--local_irq_count[cpu];
+}
+
+static inline int hardirq_trylock(int cpu)
+{
+	unsigned long flags;
+
+	__save_flags(flags);
+	__cli();
+	atomic_inc(&global_irq_count);
+	if (global_irq_count != 1 || test_bit(0,&global_irq_lock)) {
+		atomic_dec(&global_irq_count);
+		__restore_flags(flags);
+		return 0;
+	}
+	++local_irq_count[cpu];
+	__sti();
+	return 1;
+}
+
+static inline void hardirq_endlock(int cpu)
+{
+	__cli();
+	hardirq_exit(cpu);
+	__sti();
+}	
+
+#endif /* __SMP__ */
+
+#endif /* __ASM_HARDIRQ_H */