thread_info.h revision b407fc57b815b2016186220baabc76cc8264206e
1/* thread_info.h: low-level thread information 2 * 3 * Copyright (C) 2002 David Howells (dhowells@redhat.com) 4 * - Incorporating suggestions made by Linus Torvalds and Dave Miller 5 */ 6 7#ifndef _ASM_X86_THREAD_INFO_H 8#define _ASM_X86_THREAD_INFO_H 9 10#include <linux/compiler.h> 11#include <asm/page.h> 12#include <asm/types.h> 13 14/* 15 * low level task data that entry.S needs immediate access to 16 * - this struct should fit entirely inside of one cache line 17 * - this struct shares the supervisor stack pages 18 */ 19#ifndef __ASSEMBLY__ 20struct task_struct; 21struct exec_domain; 22#include <asm/processor.h> 23#include <asm/ftrace.h> 24#include <asm/atomic.h> 25 26struct thread_info { 27 struct task_struct *task; /* main task structure */ 28 struct exec_domain *exec_domain; /* execution domain */ 29 __u32 flags; /* low level flags */ 30 __u32 status; /* thread synchronous flags */ 31 __u32 cpu; /* current CPU */ 32 int preempt_count; /* 0 => preemptable, 33 <0 => BUG */ 34 mm_segment_t addr_limit; 35 struct restart_block restart_block; 36 void __user *sysenter_return; 37#ifdef CONFIG_X86_32 38 unsigned long previous_esp; /* ESP of the previous stack in 39 case of nested (IRQ) stacks 40 */ 41 __u8 supervisor_stack[0]; 42#endif 43 int uaccess_err; 44}; 45 46#define INIT_THREAD_INFO(tsk) \ 47{ \ 48 .task = &tsk, \ 49 .exec_domain = &default_exec_domain, \ 50 .flags = 0, \ 51 .cpu = 0, \ 52 .preempt_count = 1, \ 53 .addr_limit = KERNEL_DS, \ 54 .restart_block = { \ 55 .fn = do_no_restart_syscall, \ 56 }, \ 57} 58 59#define init_thread_info (init_thread_union.thread_info) 60#define init_stack (init_thread_union.stack) 61 62#else /* !__ASSEMBLY__ */ 63 64#include <asm/asm-offsets.h> 65 66#endif 67 68/* 69 * thread information flags 70 * - these are process state flags that various assembly files 71 * may need to access 72 * - pending work-to-be-done flags are in LSW 73 * - other flags in MSW 74 * Warning: layout of LSW is hardcoded in entry.S 75 */ 76#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 77#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 78#define TIF_SIGPENDING 2 /* signal pending */ 79#define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 80#define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 81#define TIF_IRET 5 /* force IRET */ 82#define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 83#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 84#define TIF_SECCOMP 8 /* secure computing */ 85#define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ 86#define TIF_NOTSC 16 /* TSC is not accessible in userland */ 87#define TIF_IA32 17 /* 32bit process */ 88#define TIF_FORK 18 /* ret_from_fork */ 89#define TIF_ABI_PENDING 19 90#define TIF_MEMDIE 20 91#define TIF_DEBUG 21 /* uses debug registers */ 92#define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 93#define TIF_FREEZE 23 /* is freezing for suspend */ 94#define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 95#define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ 96#define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */ 97#define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ 98 99#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 100#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 101#define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 102#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 103#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 104#define _TIF_IRET (1 << TIF_IRET) 105#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 106#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 107#define _TIF_SECCOMP (1 << TIF_SECCOMP) 108#define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 109#define _TIF_NOTSC (1 << TIF_NOTSC) 110#define _TIF_IA32 (1 << TIF_IA32) 111#define _TIF_FORK (1 << TIF_FORK) 112#define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING) 113#define _TIF_DEBUG (1 << TIF_DEBUG) 114#define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 115#define _TIF_FREEZE (1 << TIF_FREEZE) 116#define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 117#define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR) 118#define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR) 119#define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) 120 121/* work to do in syscall_trace_enter() */ 122#define _TIF_WORK_SYSCALL_ENTRY \ 123 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | \ 124 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | _TIF_SINGLESTEP) 125 126/* work to do in syscall_trace_leave() */ 127#define _TIF_WORK_SYSCALL_EXIT \ 128 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP) 129 130/* work to do on interrupt/exception return */ 131#define _TIF_WORK_MASK \ 132 (0x0000FFFF & \ 133 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 134 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 135 136/* work to do on any return to user space */ 137#define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP) 138 139/* Only used for 64 bit */ 140#define _TIF_DO_NOTIFY_MASK \ 141 (_TIF_SIGPENDING|_TIF_MCE_NOTIFY|_TIF_NOTIFY_RESUME) 142 143/* flags to check in __switch_to() */ 144#define _TIF_WORK_CTXSW \ 145 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_NOTSC) 146 147#define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW 148#define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG) 149 150#define PREEMPT_ACTIVE 0x10000000 151 152/* thread information allocation */ 153#ifdef CONFIG_DEBUG_STACK_USAGE 154#define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO) 155#else 156#define THREAD_FLAGS GFP_KERNEL 157#endif 158 159#define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 160 161#define alloc_thread_info(tsk) \ 162 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER)) 163 164#ifdef CONFIG_X86_32 165 166#define STACK_WARN (THREAD_SIZE/8) 167/* 168 * macros/functions for gaining access to the thread information structure 169 * 170 * preempt_count needs to be 1 initially, until the scheduler is functional. 171 */ 172#ifndef __ASSEMBLY__ 173 174 175/* how to get the current stack pointer from C */ 176register unsigned long current_stack_pointer asm("esp") __used; 177 178/* how to get the thread information struct from C */ 179static inline struct thread_info *current_thread_info(void) 180{ 181 return (struct thread_info *) 182 (current_stack_pointer & ~(THREAD_SIZE - 1)); 183} 184 185#else /* !__ASSEMBLY__ */ 186 187/* how to get the thread information struct from ASM */ 188#define GET_THREAD_INFO(reg) \ 189 movl $-THREAD_SIZE, reg; \ 190 andl %esp, reg 191 192/* use this one if reg already contains %esp */ 193#define GET_THREAD_INFO_WITH_ESP(reg) \ 194 andl $-THREAD_SIZE, reg 195 196#endif 197 198#else /* X86_32 */ 199 200#include <asm/percpu.h> 201#define KERNEL_STACK_OFFSET (5*8) 202 203/* 204 * macros/functions for gaining access to the thread information structure 205 * preempt_count needs to be 1 initially, until the scheduler is functional. 206 */ 207#ifndef __ASSEMBLY__ 208DECLARE_PER_CPU(unsigned long, kernel_stack); 209 210static inline struct thread_info *current_thread_info(void) 211{ 212 struct thread_info *ti; 213 ti = (void *)(percpu_read(kernel_stack) + 214 KERNEL_STACK_OFFSET - THREAD_SIZE); 215 return ti; 216} 217 218#else /* !__ASSEMBLY__ */ 219 220/* how to get the thread information struct from ASM */ 221#define GET_THREAD_INFO(reg) \ 222 movq PER_CPU_VAR(kernel_stack),reg ; \ 223 subq $(THREAD_SIZE-KERNEL_STACK_OFFSET),reg 224 225#endif 226 227#endif /* !X86_32 */ 228 229/* 230 * Thread-synchronous status. 231 * 232 * This is different from the flags in that nobody else 233 * ever touches our thread-synchronous status, so we don't 234 * have to worry about atomic accesses. 235 */ 236#define TS_USEDFPU 0x0001 /* FPU was used by this task 237 this quantum (SMP) */ 238#define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 239#define TS_POLLING 0x0004 /* true if in idle loop 240 and not sleeping */ 241#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 242#define TS_XSAVE 0x0010 /* Use xsave/xrstor */ 243 244#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) 245 246#ifndef __ASSEMBLY__ 247#define HAVE_SET_RESTORE_SIGMASK 1 248static inline void set_restore_sigmask(void) 249{ 250 struct thread_info *ti = current_thread_info(); 251 ti->status |= TS_RESTORE_SIGMASK; 252 set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags); 253} 254#endif /* !__ASSEMBLY__ */ 255 256#ifndef __ASSEMBLY__ 257extern void arch_task_cache_init(void); 258extern void free_thread_info(struct thread_info *ti); 259extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 260#define arch_task_cache_init arch_task_cache_init 261#endif 262#endif /* _ASM_X86_THREAD_INFO_H */ 263