1 /* thread_info.h: description
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 * Derived from include/asm-i386/thread_info.h
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
13 #ifndef _ASM_THREAD_INFO_H
14 #define _ASM_THREAD_INFO_H
19 #include <asm/processor.h>
22 #define THREAD_SIZE 8192
25 * low level task data that entry.S needs immediate access to
26 * - this struct should fit entirely inside of one cache line
27 * - this struct shares the supervisor stack pages
28 * - if the contents of this structure are changed, the assembly constants must also be changed
33 struct task_struct
*task
; /* main task structure */
34 struct exec_domain
*exec_domain
; /* execution domain */
35 unsigned long flags
; /* low level flags */
36 unsigned long status
; /* thread-synchronous flags */
37 __u32 cpu
; /* current CPU */
38 int preempt_count
; /* 0 => preemptable, <0 => BUG */
40 mm_segment_t addr_limit
; /* thread address space:
41 * 0-0xBFFFFFFF for user-thead
42 * 0-0xFFFFFFFF for kernel-thread
44 struct restart_block restart_block
;
46 __u8 supervisor_stack
[0];
49 #else /* !__ASSEMBLY__ */
51 #include <asm/asm-offsets.h>
55 #define PREEMPT_ACTIVE 0x10000000
58 * macros/functions for gaining access to the thread information structure
60 * preempt_count needs to be 1 initially, until the scheduler is functional.
64 #define INIT_THREAD_INFO(tsk) \
67 .exec_domain = &default_exec_domain, \
71 .addr_limit = KERNEL_DS, \
73 .fn = do_no_restart_syscall, \
77 #define init_thread_info (init_thread_union.thread_info)
78 #define init_stack (init_thread_union.stack)
80 /* how to get the thread information struct from C */
81 register struct thread_info
*__current_thread_info
asm("gr15");
83 #define current_thread_info() ({ __current_thread_info; })
85 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
87 /* thread information allocation */
88 #ifdef CONFIG_DEBUG_STACK_USAGE
89 #define alloc_thread_info(tsk) \
91 struct thread_info *ret; \
93 ret = kzalloc(THREAD_SIZE, GFP_KERNEL); \
98 #define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
101 #define free_thread_info(info) kfree(info)
103 #endif /* __ASSEMBLY__ */
106 * thread information flags
107 * - these are process state flags that various assembly files may need to access
108 * - pending work-to-be-done flags are in LSW
109 * - other flags in MSW
111 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
112 #define TIF_SIGPENDING 1 /* signal pending */
113 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
114 #define TIF_SINGLESTEP 3 /* restore singlestep on return to user mode */
115 #define TIF_IRET 4 /* return with iret */
116 #define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
117 #define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */
118 #define TIF_MEMDIE 17 /* OOM killer killed process */
119 #define TIF_FREEZE 18 /* freezing for suspend */
121 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
122 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
123 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
124 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
125 #define _TIF_IRET (1 << TIF_IRET)
126 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
127 #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG)
128 #define _TIF_FREEZE (1 << TIF_FREEZE)
130 #define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
131 #define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */
134 * Thread-synchronous status.
136 * This is different from the flags in that nobody else
137 * ever touches our thread-synchronous status, so we don't
138 * have to worry about atomic accesses.
140 #define TS_USEDFPM 0x0001 /* FPU/Media was used by this task this quantum (SMP) */
142 #endif /* __KERNEL__ */
144 #endif /* _ASM_THREAD_INFO_H */