/* thread_info.h: description * * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * Derived from include/asm-i386/thread_info.h * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #ifndef _ASM_THREAD_INFO_H#define _ASM_THREAD_INFO_H #ifdef __KERNEL__ #ifndef __ASSEMBLY__#include <asm/processor.h>#endif /* * low level task data that entry.S needs immediate access to * - this struct should fit entirely inside of one cache line * - this struct shares the supervisor stack pages * - if the contents of this structure are changed, the assembly constants must also be changed */#ifndef __ASSEMBLY__ struct thread_info {	struct task_struct	*task;		/* main task structure */	struct exec_domain	*exec_domain;	/* execution domain */	unsigned long		flags;		/* low level flags */	unsigned long		status;		/* thread-synchronous flags */	__u32			cpu;		/* current CPU */	int			preempt_count;	/* 0 => preemptable, <0 => BUG */ 	mm_segment_t		addr_limit;	/* thread address space:					 	   0-0xBFFFFFFF for user-thead						   0-0xFFFFFFFF for kernel-thread						*/	struct restart_block    restart_block; 	__u8			supervisor_stack[0];}; #else /* !__ASSEMBLY__ */ /* offsets into the thread_info struct for assembly code access */#define TI_TASK			0x00000000#define TI_EXEC_DOMAIN		0x00000004#define TI_FLAGS		0x00000008#define TI_STATUS		0x0000000C#define TI_CPU			0x00000010#define TI_PRE_COUNT		0x00000014#define TI_ADDR_LIMIT		0x00000018#define TI_RESTART_BLOCK	0x0000001C #endif #define PREEMPT_ACTIVE		0x10000000 /* * macros/functions for gaining access to the thread information structure * * preempt_count needs to be 1 initially, until the scheduler is functional. */#ifndef __ASSEMBLY__ #define INIT_THREAD_INFO(tsk)			\{						\	.task		= &tsk,			\	.exec_domain	= &default_exec_domain,	\	.flags		= 0,			\	.cpu		= 0,			\	.preempt_count	= 1,			\	.addr_limit	= KERNEL_DS,		\	.restart_block = {			\		.fn = do_no_restart_syscall,	\	},					\} #define init_thread_info	(init_thread_union.thread_info)#define init_stack		(init_thread_union.stack) #ifdef CONFIG_SMALL_TASKS#define THREAD_SIZE		4096#else#define THREAD_SIZE		8192#endif /* how to get the thread information struct from C */register struct thread_info *__current_thread_info asm("gr15"); #define current_thread_info() ({ __current_thread_info; }) /* thread information allocation */#ifdef CONFIG_DEBUG_STACK_USAGE#define alloc_thread_info(tsk)					\	({							\		struct thread_info *ret;			\								\		ret = kmalloc(THREAD_SIZE, GFP_KERNEL);		\		if (ret)					\			memset(ret, 0, THREAD_SIZE);		\		ret;						\	})#else#define alloc_thread_info(tsk)	kmalloc(THREAD_SIZE, GFP_KERNEL)#endif #define free_thread_info(info)	kfree(info) #else /* !__ASSEMBLY__ */ #define THREAD_SIZE	8192 #endif /* * thread information flags * - these are process state flags that various assembly files may need to access * - pending work-to-be-done flags are in LSW * - other flags in MSW */#define TIF_SYSCALL_TRACE	0	/* syscall trace active */#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */#define TIF_SIGPENDING		2	/* signal pending */#define TIF_NEED_RESCHED	3	/* rescheduling necessary */#define TIF_SINGLESTEP		4	/* restore singlestep on return to user mode */#define TIF_IRET		5	/* return with iret */#define TIF_RESTORE_SIGMASK	6	/* restore signal mask in do_signal() */#define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling TIF_NEED_RESCHED */#define TIF_MEMDIE		17	/* OOM killer killed process */ #define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)#define _TIF_SINGLESTEP		(1 << TIF_SINGLESTEP)#define _TIF_IRET		(1 << TIF_IRET)#define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)#define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG) #define _TIF_WORK_MASK		0x0000FFFE	/* work to do on interrupt/exception return */#define _TIF_ALLWORK_MASK	0x0000FFFF	/* work to do on any return to u-space */ /* * Thread-synchronous status. * * This is different from the flags in that nobody else * ever touches our thread-synchronous status, so we don't * have to worry about atomic accesses. */#define TS_USEDFPM		0x0001	/* FPU/Media was used by this task this quantum (SMP) */ #endif /* __KERNEL__ */ #endif /* _ASM_THREAD_INFO_H */