thread_info.h revision c2724775ce57c98b8af9694857b941dc61056516
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 unsigned long 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}; 44 45#define INIT_THREAD_INFO(tsk) \ 46{ \ 47 .task = &tsk, \ 48 .exec_domain = &default_exec_domain, \ 49 .flags = 0, \ 50 .cpu = 0, \ 51 .preempt_count = 1, \ 52 .addr_limit = KERNEL_DS, \ 53 .restart_block = { \ 54 .fn = do_no_restart_syscall, \ 55 }, \ 56} 57 58#define init_thread_info (init_thread_union.thread_info) 59#define init_stack (init_thread_union.stack) 60 61#else /* !__ASSEMBLY__ */ 62 63#include <asm/asm-offsets.h> 64 65#endif 66 67/* 68 * thread information flags 69 * - these are process state flags that various assembly files 70 * may need to access 71 * - pending work-to-be-done flags are in LSW 72 * - other flags in MSW 73 * Warning: layout of LSW is hardcoded in entry.S 74 */ 75#define TIF_SYSCALL_TRACE 0 /* syscall trace active */ 76#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */ 77#define TIF_SIGPENDING 2 /* signal pending */ 78#define TIF_NEED_RESCHED 3 /* rescheduling necessary */ 79#define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ 80#define TIF_IRET 5 /* force IRET */ 81#define TIF_SYSCALL_EMU 6 /* syscall emulation active */ 82#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ 83#define TIF_SECCOMP 8 /* secure computing */ 84#define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ 85#define TIF_NOTSC 16 /* TSC is not accessible in userland */ 86#define TIF_IA32 17 /* 32bit process */ 87#define TIF_FORK 18 /* ret_from_fork */ 88#define TIF_ABI_PENDING 19 89#define TIF_MEMDIE 20 90#define TIF_DEBUG 21 /* uses debug registers */ 91#define TIF_IO_BITMAP 22 /* uses I/O bitmap */ 92#define TIF_FREEZE 23 /* is freezing for suspend */ 93#define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ 94#define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ 95#define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */ 96 97#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) 98#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) 99#define _TIF_SIGPENDING (1 << TIF_SIGPENDING) 100#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) 101#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) 102#define _TIF_IRET (1 << TIF_IRET) 103#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) 104#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) 105#define _TIF_SECCOMP (1 << TIF_SECCOMP) 106#define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) 107#define _TIF_NOTSC (1 << TIF_NOTSC) 108#define _TIF_IA32 (1 << TIF_IA32) 109#define _TIF_FORK (1 << TIF_FORK) 110#define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING) 111#define _TIF_DEBUG (1 << TIF_DEBUG) 112#define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP) 113#define _TIF_FREEZE (1 << TIF_FREEZE) 114#define _TIF_FORCED_TF (1 << TIF_FORCED_TF) 115#define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR) 116#define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR) 117 118/* work to do in syscall_trace_enter() */ 119#define _TIF_WORK_SYSCALL_ENTRY \ 120 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | \ 121 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | _TIF_SINGLESTEP) 122 123/* work to do in syscall_trace_leave() */ 124#define _TIF_WORK_SYSCALL_EXIT \ 125 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP) 126 127/* work to do on interrupt/exception return */ 128#define _TIF_WORK_MASK \ 129 (0x0000FFFF & \ 130 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \ 131 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU)) 132 133/* work to do on any return to user space */ 134#define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP) 135 136/* Only used for 64 bit */ 137#define _TIF_DO_NOTIFY_MASK \ 138 (_TIF_SIGPENDING|_TIF_MCE_NOTIFY|_TIF_NOTIFY_RESUME) 139 140/* flags to check in __switch_to() */ 141#define _TIF_WORK_CTXSW \ 142 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_NOTSC) 143 144#define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW 145#define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG) 146 147#define PREEMPT_ACTIVE 0x10000000 148 149/* thread information allocation */ 150#ifdef CONFIG_DEBUG_STACK_USAGE 151#define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO) 152#else 153#define THREAD_FLAGS GFP_KERNEL 154#endif 155 156#define __HAVE_ARCH_THREAD_INFO_ALLOCATOR 157 158#define alloc_thread_info(tsk) \ 159 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER)) 160 161#ifdef CONFIG_X86_32 162 163#define STACK_WARN (THREAD_SIZE/8) 164/* 165 * macros/functions for gaining access to the thread information structure 166 * 167 * preempt_count needs to be 1 initially, until the scheduler is functional. 168 */ 169#ifndef __ASSEMBLY__ 170 171 172/* how to get the current stack pointer from C */ 173register unsigned long current_stack_pointer asm("esp") __used; 174 175/* how to get the thread information struct from C */ 176static inline struct thread_info *current_thread_info(void) 177{ 178 return (struct thread_info *) 179 (current_stack_pointer & ~(THREAD_SIZE - 1)); 180} 181 182#else /* !__ASSEMBLY__ */ 183 184/* how to get the thread information struct from ASM */ 185#define GET_THREAD_INFO(reg) \ 186 movl $-THREAD_SIZE, reg; \ 187 andl %esp, reg 188 189/* use this one if reg already contains %esp */ 190#define GET_THREAD_INFO_WITH_ESP(reg) \ 191 andl $-THREAD_SIZE, reg 192 193#endif 194 195#else /* X86_32 */ 196 197#include <asm/pda.h> 198 199/* 200 * macros/functions for gaining access to the thread information structure 201 * preempt_count needs to be 1 initially, until the scheduler is functional. 202 */ 203#ifndef __ASSEMBLY__ 204static inline struct thread_info *current_thread_info(void) 205{ 206 struct thread_info *ti; 207 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE); 208 return ti; 209} 210 211/* do not use in interrupt context */ 212static inline struct thread_info *stack_thread_info(void) 213{ 214 struct thread_info *ti; 215 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1))); 216 return ti; 217} 218 219#else /* !__ASSEMBLY__ */ 220 221/* how to get the thread information struct from ASM */ 222#define GET_THREAD_INFO(reg) \ 223 movq %gs:pda_kernelstack,reg ; \ 224 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg 225 226#endif 227 228#endif /* !X86_32 */ 229 230/* 231 * Thread-synchronous status. 232 * 233 * This is different from the flags in that nobody else 234 * ever touches our thread-synchronous status, so we don't 235 * have to worry about atomic accesses. 236 */ 237#define TS_USEDFPU 0x0001 /* FPU was used by this task 238 this quantum (SMP) */ 239#define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ 240#define TS_POLLING 0x0004 /* true if in idle loop 241 and not sleeping */ 242#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */ 243#define TS_XSAVE 0x0010 /* Use xsave/xrstor */ 244 245#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING) 246 247#ifndef __ASSEMBLY__ 248#define HAVE_SET_RESTORE_SIGMASK 1 249static inline void set_restore_sigmask(void) 250{ 251 struct thread_info *ti = current_thread_info(); 252 ti->status |= TS_RESTORE_SIGMASK; 253 set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags); 254} 255#endif /* !__ASSEMBLY__ */ 256 257#ifndef __ASSEMBLY__ 258extern void arch_task_cache_init(void); 259extern void free_thread_info(struct thread_info *ti); 260extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); 261#define arch_task_cache_init arch_task_cache_init 262#endif 263#endif /* _ASM_X86_THREAD_INFO_H */ 264