1 /* thread_info.h: description 2 * 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 6 * 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. 11 */ 12 13 #ifndef _ASM_THREAD_INFO_H 14 #define _ASM_THREAD_INFO_H 15 16 #ifdef __KERNEL__ 17 18 #ifndef __ASSEMBLY__ 19 #include <asm/processor.h> 20 #endif 21 22 #define THREAD_SIZE 8192 23 24 #define __HAVE_ARCH_TASK_STRUCT_ALLOCATOR 25 26 /* 27 * low level task data that entry.S needs immediate access to 28 * - this struct should fit entirely inside of one cache line 29 * - this struct shares the supervisor stack pages 30 * - if the contents of this structure are changed, the assembly constants must also be changed 31 */ 32 #ifndef __ASSEMBLY__ 33 34 struct thread_info { 35 struct task_struct *task; /* main task structure */ 36 struct exec_domain *exec_domain; /* execution domain */ 37 unsigned long flags; /* low level flags */ 38 unsigned long status; /* thread-synchronous flags */ 39 __u32 cpu; /* current CPU */ 40 int preempt_count; /* 0 => preemptable, <0 => BUG */ 41 42 mm_segment_t addr_limit; /* thread address space: 43 * 0-0xBFFFFFFF for user-thead 44 * 0-0xFFFFFFFF for kernel-thread 45 */ 46 struct restart_block restart_block; 47 48 __u8 supervisor_stack[0]; 49 }; 50 51 #else /* !__ASSEMBLY__ */ 52 53 #include <asm/asm-offsets.h> 54 55 #endif 56 57 #define PREEMPT_ACTIVE 0x10000000 58 59 /* 60 * macros/functions for gaining access to the thread information structure 61 */ 62 #ifndef __ASSEMBLY__ 63 64 #define INIT_THREAD_INFO(tsk) \ 65 { \ 66 .task = &tsk, \ 67 .exec_domain = &default_exec_domain, \ 68 .flags = 0, \ 69 .cpu = 0, \ 70 .preempt_count = INIT_PREEMPT_COUNT, \ 71 .addr_limit = KERNEL_DS, \ 72 .restart_block = { \ 73 .fn = do_no_restart_syscall, \ 74 }, \ 75 } 76 77 #define init_thread_info (init_thread_union.thread_info) 78 #define init_stack (init_thread_union.stack) 79 80 /* how to get the thread information struct from C */ 81 register struct thread_info *__current_thread_info asm("gr15"); 82 83 #define current_thread_info() ({ __current_thread_info; }) 84 85 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 86 87 /* thread information allocation */ 88 #ifdef CONFIG_DEBUG_STACK_USAGE 89 #define alloc_thread_info_node(tsk, node) \ 90 kzalloc_node(THREAD_SIZE, GFP_KERNEL, node) 91 #else 92 #define alloc_thread_info_node(tsk, node) \ 93 kmalloc_node(THREAD_SIZE, GFP_KERNEL, node) 94 #endif 95 96 #define free_thread_info(info) kfree(info) 97 98 #endif /* __ASSEMBLY__ */ 99 100 /* 101 * thread information flags 102 * - these are process state flags that various assembly files may need to access 103 * - pending work-to-be-done flags are in LSW 104 * - other flags in MSW 105 */ 106 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 107 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 108 #define TIF_SIGPENDING 2 /* signal pending */ 109 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 110 #define TIF_SINGLESTEP 4 /* restore singlestep on return to user mode */ 111 #define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */ 112 #define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */ 113 #define TIF_MEMDIE 17 /* is terminating due to OOM killer */ 114 115 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 116 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 117 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 118 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 119 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 120 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) 121 #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) 122 123 #define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */ 124 #define _TIF_ALLWORK_MASK 0x0000FFFF /* work to do on any return to u-space */ 125 126 /* 127 * Thread-synchronous status. 128 * 129 * This is different from the flags in that nobody else 130 * ever touches our thread-synchronous status, so we don't 131 * have to worry about atomic accesses. 132 */ 133 #define TS_USEDFPM 0x0001 /* FPU/Media was used by this task this quantum (SMP) */ 134 135 #endif /* __KERNEL__ */ 136 137 #endif /* _ASM_THREAD_INFO_H */ 138