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Diffstat (limited to 'include/asm-s390x/hardirq.h')
| -rw-r--r-- | include/asm-s390x/hardirq.h | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/include/asm-s390x/hardirq.h b/include/asm-s390x/hardirq.h new file mode 100644 index 000000000..d5ec49dde --- /dev/null +++ b/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 */ |