patch-2.4.2 linux/include/asm-s390x/hardirq.h

• Lines: 109
• Date: Tue Feb 13 14:13:44 2001
• Orig file: v2.4.1/linux/include/asm-s390x/hardirq.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.1/linux/include/asm-s390x/hardirq.h linux/include/asm-s390x/hardirq.h
@@ -0,0 +1,108 @@
+/*
+ *  include/asm-s390/hardirq.h
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ *               Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
+ *
+ *  Derived from "include/asm-i386/hardirq.h"
+ */
+
+#ifndef __ASM_HARDIRQ_H
+#define __ASM_HARDIRQ_H
+
+#include <linux/config.h>
+#include <linux/threads.h>
+#include <asm/lowcore.h>
+#include <linux/sched.h>
+
+/* No irq_cpustat_t for s390, the data is held directly in S390_lowcore */
+
+/*
+ * Simple wrappers reducing source bloat.  S390 specific because each
+ * cpu stores its data in S390_lowcore (PSA) instead of using a cache
+ * aligned array element like most architectures.
+ */
+
+#ifdef CONFIG_SMP
+
+#define softirq_active(cpu)	(safe_get_cpu_lowcore(cpu).__softirq_active)
+#define softirq_mask(cpu)	(safe_get_cpu_lowcore(cpu).__softirq_mask)
+#define local_irq_count(cpu)	(safe_get_cpu_lowcore(cpu).__local_irq_count)
+#define local_bh_count(cpu)	(safe_get_cpu_lowcore(cpu).__local_bh_count)
+#define syscall_count(cpu)	(safe_get_cpu_lowcore(cpu).__syscall_count)
+
+#else	/* CONFIG_SMP */
+
+/* Optimize away the cpu calculation, it is always current PSA */
+#define softirq_active(cpu)	((void)(cpu), S390_lowcore.__softirq_active)
+#define softirq_mask(cpu)	((void)(cpu), S390_lowcore.__softirq_mask)
+#define local_irq_count(cpu)	((void)(cpu), S390_lowcore.__local_irq_count)
+#define local_bh_count(cpu)	((void)(cpu), S390_lowcore.__local_bh_count)
+#define syscall_count(cpu)	((void)(cpu), S390_lowcore.__syscall_count)
+
+#endif	/* CONFIG_SMP */
+
+/*
+ * Are we in an interrupt context? Either doing bottom half
+ * or hardware interrupt processing?
+ * Special definitions for s390, always access current PSA.
+ */
+#define in_interrupt() ((S390_lowcore.__local_irq_count + S390_lowcore.__local_bh_count) != 0)
+  
+#define in_irq() (S390_lowcore.__local_irq_count != 0)
+  
+#ifndef CONFIG_SMP
+  
+#define hardirq_trylock(cpu)	(local_irq_count(cpu) == 0)
+#define hardirq_endlock(cpu)	do { } while (0)
+  
+#define hardirq_enter(cpu)	(local_irq_count(cpu)++)
+#define hardirq_exit(cpu)	(local_irq_count(cpu)--)
+
+#define synchronize_irq()	do { } while (0)
+
+#else
+
+#include <asm/atomic.h>
+#include <asm/smp.h>
+
+extern atomic_t global_irq_holder;
+extern atomic_t global_irq_lock;
+extern atomic_t global_irq_count;
+
+static inline void release_irqlock(int cpu)
+{
+	/* if we didn't own the irq lock, just ignore.. */
+	if (atomic_read(&global_irq_holder) ==  cpu) {
+		atomic_set(&global_irq_holder,NO_PROC_ID);
+                atomic_set(&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)
+{
+	return !atomic_read(&global_irq_count) && 
+               !atomic_read(&global_irq_lock);
+}
+
+#define hardirq_endlock(cpu)	do { } while (0)
+
+extern void synchronize_irq(void);
+
+#endif /* CONFIG_SMP */
+
+#endif /* __ASM_HARDIRQ_H */