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