1 /* thread_info.h: low-level thread information
3 * Copyright (C) 2002 David Howells (dhowells@redhat.com)
4 * - Incorporating suggestions made by Linus Torvalds and Dave Miller
7 #ifndef _ASM_X86_THREAD_INFO_H
8 #define _ASM_X86_THREAD_INFO_H
10 #include <linux/compiler.h>
12 #include <asm/types.h>
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
22 #include <asm/processor.h>
23 #include <asm/ftrace.h>
26 struct task_struct *task; /* main task structure */
27 struct exec_domain *exec_domain; /* execution domain */
28 unsigned long flags; /* low level flags */
29 __u32 status; /* thread synchronous flags */
30 __u32 cpu; /* current CPU */
31 int preempt_count; /* 0 => preemptable,
33 mm_segment_t addr_limit;
34 struct restart_block restart_block;
35 void __user *sysenter_return;
37 unsigned long previous_esp; /* ESP of the previous stack in
38 case of nested (IRQ) stacks
40 __u8 supervisor_stack[0];
43 #ifdef CONFIG_FUNCTION_RET_TRACER
44 /* Index of current stored adress in ret_stack */
46 /* Stack of return addresses for return function tracing */
47 struct ftrace_ret_stack ret_stack[FTRACE_RET_STACK_SIZE];
51 #ifdef CONFIG_FUNCTION_RET_TRACER
52 #define INIT_THREAD_INFO(tsk) \
55 .exec_domain = &default_exec_domain, \
59 .addr_limit = KERNEL_DS, \
61 .fn = do_no_restart_syscall, \
63 .curr_ret_stack = -1,\
66 #define INIT_THREAD_INFO(tsk) \
69 .exec_domain = &default_exec_domain, \
73 .addr_limit = KERNEL_DS, \
75 .fn = do_no_restart_syscall, \
80 #define init_thread_info (init_thread_union.thread_info)
81 #define init_stack (init_thread_union.stack)
83 #else /* !__ASSEMBLY__ */
85 #include <asm/asm-offsets.h>
90 * thread information flags
91 * - these are process state flags that various assembly files
93 * - pending work-to-be-done flags are in LSW
94 * - other flags in MSW
95 * Warning: layout of LSW is hardcoded in entry.S
97 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
98 #define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
99 #define TIF_SIGPENDING 2 /* signal pending */
100 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
101 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
102 #define TIF_IRET 5 /* force IRET */
103 #define TIF_SYSCALL_EMU 6 /* syscall emulation active */
104 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
105 #define TIF_SECCOMP 8 /* secure computing */
106 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */
107 #define TIF_NOTSC 16 /* TSC is not accessible in userland */
108 #define TIF_IA32 17 /* 32bit process */
109 #define TIF_FORK 18 /* ret_from_fork */
110 #define TIF_ABI_PENDING 19
111 #define TIF_MEMDIE 20
112 #define TIF_DEBUG 21 /* uses debug registers */
113 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */
114 #define TIF_FREEZE 23 /* is freezing for suspend */
115 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
116 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */
117 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */
118 #define TIF_BTS_TRACE_TS 27 /* record scheduling event timestamps */
120 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
121 #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
122 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
123 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
124 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
125 #define _TIF_IRET (1 << TIF_IRET)
126 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
127 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
128 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
129 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY)
130 #define _TIF_NOTSC (1 << TIF_NOTSC)
131 #define _TIF_IA32 (1 << TIF_IA32)
132 #define _TIF_FORK (1 << TIF_FORK)
133 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING)
134 #define _TIF_DEBUG (1 << TIF_DEBUG)
135 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
136 #define _TIF_FREEZE (1 << TIF_FREEZE)
137 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
138 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
139 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
140 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
142 /* work to do in syscall_trace_enter() */
143 #define _TIF_WORK_SYSCALL_ENTRY \
144 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | \
145 _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | _TIF_SINGLESTEP)
147 /* work to do in syscall_trace_leave() */
148 #define _TIF_WORK_SYSCALL_EXIT \
149 (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SINGLESTEP)
151 /* work to do on interrupt/exception return */
152 #define _TIF_WORK_MASK \
154 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT| \
155 _TIF_SINGLESTEP|_TIF_SECCOMP|_TIF_SYSCALL_EMU))
157 /* work to do on any return to user space */
158 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
160 /* Only used for 64 bit */
161 #define _TIF_DO_NOTIFY_MASK \
162 (_TIF_SIGPENDING|_TIF_MCE_NOTIFY|_TIF_NOTIFY_RESUME)
164 /* flags to check in __switch_to() */
165 #define _TIF_WORK_CTXSW \
166 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS| \
169 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
170 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG)
172 #define PREEMPT_ACTIVE 0x10000000
174 /* thread information allocation */
175 #ifdef CONFIG_DEBUG_STACK_USAGE
176 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO)
178 #define THREAD_FLAGS GFP_KERNEL
181 #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
183 #define alloc_thread_info(tsk) \
184 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER))
188 #define STACK_WARN (THREAD_SIZE/8)
190 * macros/functions for gaining access to the thread information structure
192 * preempt_count needs to be 1 initially, until the scheduler is functional.
197 /* how to get the current stack pointer from C */
198 register unsigned long current_stack_pointer asm("esp") __used;
200 /* how to get the thread information struct from C */
201 static inline struct thread_info *current_thread_info(void)
203 return (struct thread_info *)
204 (current_stack_pointer & ~(THREAD_SIZE - 1));
207 #else /* !__ASSEMBLY__ */
209 /* how to get the thread information struct from ASM */
210 #define GET_THREAD_INFO(reg) \
211 movl $-THREAD_SIZE, reg; \
214 /* use this one if reg already contains %esp */
215 #define GET_THREAD_INFO_WITH_ESP(reg) \
216 andl $-THREAD_SIZE, reg
225 * macros/functions for gaining access to the thread information structure
226 * preempt_count needs to be 1 initially, until the scheduler is functional.
229 static inline struct thread_info *current_thread_info(void)
231 struct thread_info *ti;
232 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE);
236 /* do not use in interrupt context */
237 static inline struct thread_info *stack_thread_info(void)
239 struct thread_info *ti;
240 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1)));
244 #else /* !__ASSEMBLY__ */
246 /* how to get the thread information struct from ASM */
247 #define GET_THREAD_INFO(reg) \
248 movq %gs:pda_kernelstack,reg ; \
249 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg
256 * Thread-synchronous status.
258 * This is different from the flags in that nobody else
259 * ever touches our thread-synchronous status, so we don't
260 * have to worry about atomic accesses.
262 #define TS_USEDFPU 0x0001 /* FPU was used by this task
263 this quantum (SMP) */
264 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/
265 #define TS_POLLING 0x0004 /* true if in idle loop
267 #define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */
268 #define TS_XSAVE 0x0010 /* Use xsave/xrstor */
270 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
273 #define HAVE_SET_RESTORE_SIGMASK 1
274 static inline void set_restore_sigmask(void)
276 struct thread_info *ti = current_thread_info();
277 ti->status |= TS_RESTORE_SIGMASK;
278 set_bit(TIF_SIGPENDING, (unsigned long *)&ti->flags);
280 #endif /* !__ASSEMBLY__ */
283 extern void arch_task_cache_init(void);
284 extern void free_thread_info(struct thread_info *ti);
285 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
286 #define arch_task_cache_init arch_task_cache_init
288 #endif /* _ASM_X86_THREAD_INFO_H */