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>
17 #include <asm/processor.h>
21 * low level task data that entry.S needs immediate access to
22 * - this struct should fit entirely inside of one cache line
23 * - this struct shares the supervisor stack pages
24 * - if the contents of this structure are changed,
25 * the assembly constants must also be changed
30 struct task_struct *task; /* main task structure */
31 struct exec_domain *exec_domain; /* execution domain */
32 unsigned long flags; /* low level flags */
33 unsigned long status; /* thread-synchronous flags */
34 __u32 cpu; /* current CPU */
35 int preempt_count; /* 0 => preemptable,
37 mm_segment_t addr_limit; /* thread address space:
38 0-0xBFFFFFFF user-thread
39 0-0xFFFFFFFF kernel-thread
41 void *sysenter_return;
42 struct restart_block restart_block;
43 unsigned long previous_esp; /* ESP of the previous stack in
44 case of nested (IRQ) stacks
46 __u8 supervisor_stack[0];
49 #else /* !__ASSEMBLY__ */
51 #include <asm/asm-offsets.h>
55 #define PREEMPT_ACTIVE 0x10000000
56 #ifdef CONFIG_4KSTACKS
57 #define THREAD_SIZE (4096)
59 #define THREAD_SIZE (8192)
62 #define STACK_WARN (THREAD_SIZE/8)
64 * macros/functions for gaining access to the thread information structure
66 * preempt_count needs to be 1 initially, until the scheduler is functional.
70 #define INIT_THREAD_INFO(tsk) \
73 .exec_domain = &default_exec_domain, \
77 .addr_limit = KERNEL_DS, \
79 .fn = do_no_restart_syscall, \
83 #define init_thread_info (init_thread_union.thread_info)
84 #define init_stack (init_thread_union.stack)
87 /* how to get the current stack pointer from C */
88 register unsigned long current_stack_pointer asm("esp") __used;
90 /* how to get the thread information struct from C */
91 static inline struct thread_info *current_thread_info(void)
93 return (struct thread_info *)
94 (current_stack_pointer & ~(THREAD_SIZE - 1));
97 /* thread information allocation */
98 #ifdef CONFIG_DEBUG_STACK_USAGE
99 #define alloc_thread_info(tsk) ((struct thread_info *) \
100 __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(THREAD_SIZE)))
102 #define alloc_thread_info(tsk) ((struct thread_info *) \
103 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE)))
106 #else /* !__ASSEMBLY__ */
108 /* how to get the thread information struct from ASM */
109 #define GET_THREAD_INFO(reg) \
110 movl $-THREAD_SIZE, reg; \
113 /* use this one if reg already contains %esp */
114 #define GET_THREAD_INFO_WITH_ESP(reg) \
115 andl $-THREAD_SIZE, reg
120 * thread information flags
121 * - these are process state flags that various
122 * assembly files may need to access
123 * - pending work-to-be-done flags are in LSW
124 * - other flags in MSW
126 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
127 #define TIF_SIGPENDING 1 /* signal pending */
128 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
129 #define TIF_SINGLESTEP 3 /* restore singlestep on return to
131 #define TIF_IRET 4 /* return with iret */
132 #define TIF_SYSCALL_EMU 5 /* syscall emulation active */
133 #define TIF_SYSCALL_AUDIT 6 /* syscall auditing active */
134 #define TIF_SECCOMP 7 /* secure computing */
135 #define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */
136 #define TIF_HRTICK_RESCHED 9 /* reprogram hrtick timer */
137 #define TIF_MEMDIE 16
138 #define TIF_DEBUG 17 /* uses debug registers */
139 #define TIF_IO_BITMAP 18 /* uses I/O bitmap */
140 #define TIF_FREEZE 19 /* is freezing for suspend */
141 #define TIF_NOTSC 20 /* TSC is not accessible in userland */
142 #define TIF_FORCED_TF 21 /* true if TF in eflags artificially */
143 #define TIF_DEBUGCTLMSR 22 /* uses thread_struct.debugctlmsr */
144 #define TIF_DS_AREA_MSR 23 /* uses thread_struct.ds_area_msr */
145 #define TIF_BTS_TRACE_TS 24 /* record scheduling event timestamps */
147 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
148 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
149 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
150 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
151 #define _TIF_IRET (1 << TIF_IRET)
152 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
153 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
154 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
155 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
156 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
157 #define _TIF_DEBUG (1 << TIF_DEBUG)
158 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
159 #define _TIF_FREEZE (1 << TIF_FREEZE)
160 #define _TIF_NOTSC (1 << TIF_NOTSC)
161 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
162 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
163 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
164 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
166 /* work to do on interrupt/exception return */
167 #define _TIF_WORK_MASK \
168 (0x0000FFFF & ~(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
169 _TIF_SECCOMP | _TIF_SYSCALL_EMU))
170 /* work to do on any return to u-space */
171 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
173 /* flags to check in __switch_to() */
174 #define _TIF_WORK_CTXSW \
175 (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUGCTLMSR | \
176 _TIF_DS_AREA_MSR | _TIF_BTS_TRACE_TS)
177 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
178 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW | _TIF_DEBUG)
182 * Thread-synchronous status.
184 * This is different from the flags in that nobody else
185 * ever touches our thread-synchronous status, so we don't
186 * have to worry about atomic accesses.
188 #define TS_USEDFPU 0x0001 /* FPU was used by this task
189 this quantum (SMP) */
190 #define TS_POLLING 0x0002 /* True if in idle loop
193 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
200 * low level task data that entry.S needs immediate access to
201 * - this struct should fit entirely inside of one cache line
202 * - this struct shares the supervisor stack pages
207 #include <asm/processor.h>
210 struct task_struct *task; /* main task structure */
211 struct exec_domain *exec_domain; /* execution domain */
212 __u32 flags; /* low level flags */
213 __u32 status; /* thread synchronous flags */
214 __u32 cpu; /* current CPU */
215 int preempt_count; /* 0 => preemptable,
217 mm_segment_t addr_limit;
218 struct restart_block restart_block;
219 #ifdef CONFIG_IA32_EMULATION
220 void __user *sysenter_return;
226 * macros/functions for gaining access to the thread information structure
227 * preempt_count needs to be 1 initially, until the scheduler is functional.
230 #define INIT_THREAD_INFO(tsk) \
233 .exec_domain = &default_exec_domain, \
236 .preempt_count = 1, \
237 .addr_limit = KERNEL_DS, \
239 .fn = do_no_restart_syscall, \
243 #define init_thread_info (init_thread_union.thread_info)
244 #define init_stack (init_thread_union.stack)
246 static inline struct thread_info *current_thread_info(void)
248 struct thread_info *ti;
249 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE);
253 /* do not use in interrupt context */
254 static inline struct thread_info *stack_thread_info(void)
256 struct thread_info *ti;
257 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1)));
261 /* thread information allocation */
262 #ifdef CONFIG_DEBUG_STACK_USAGE
263 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO)
265 #define THREAD_FLAGS GFP_KERNEL
268 #define alloc_thread_info(tsk) \
269 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER))
271 #else /* !__ASSEMBLY__ */
273 /* how to get the thread information struct from ASM */
274 #define GET_THREAD_INFO(reg) \
275 movq %gs:pda_kernelstack,reg ; \
276 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg
281 * thread information flags
282 * - these are process state flags that various assembly files
284 * - pending work-to-be-done flags are in LSW
285 * - other flags in MSW
286 * Warning: layout of LSW is hardcoded in entry.S
288 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
289 #define TIF_SIGPENDING 2 /* signal pending */
290 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
291 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
292 #define TIF_IRET 5 /* force IRET */
293 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
294 #define TIF_SECCOMP 8 /* secure computing */
295 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */
296 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */
297 #define TIF_HRTICK_RESCHED 11 /* reprogram hrtick timer */
299 #define TIF_IA32 17 /* 32bit process */
300 #define TIF_FORK 18 /* ret_from_fork */
301 #define TIF_ABI_PENDING 19
302 #define TIF_MEMDIE 20
303 #define TIF_DEBUG 21 /* uses debug registers */
304 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */
305 #define TIF_FREEZE 23 /* is freezing for suspend */
306 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
307 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */
308 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */
309 #define TIF_BTS_TRACE_TS 27 /* record scheduling event timestamps */
310 #define TIF_NOTSC 28 /* TSC is not accessible in userland */
312 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
313 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
314 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
315 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
316 #define _TIF_IRET (1 << TIF_IRET)
317 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
318 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
319 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
320 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY)
321 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
322 #define _TIF_IA32 (1 << TIF_IA32)
323 #define _TIF_FORK (1 << TIF_FORK)
324 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING)
325 #define _TIF_DEBUG (1 << TIF_DEBUG)
326 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
327 #define _TIF_FREEZE (1 << TIF_FREEZE)
328 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
329 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
330 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
331 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
332 #define _TIF_NOTSC (1 << TIF_NOTSC)
334 /* work to do on interrupt/exception return */
335 #define _TIF_WORK_MASK \
337 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP))
338 /* work to do on any return to user space */
339 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
341 #define _TIF_DO_NOTIFY_MASK \
342 (_TIF_SIGPENDING|_TIF_SINGLESTEP|_TIF_MCE_NOTIFY|_TIF_HRTICK_RESCHED)
344 /* flags to check in __switch_to() */
345 #define _TIF_WORK_CTXSW \
346 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS|_TIF_NOTSC)
347 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
348 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG)
350 #define PREEMPT_ACTIVE 0x10000000
353 * Thread-synchronous status.
355 * This is different from the flags in that nobody else
356 * ever touches our thread-synchronous status, so we don't
357 * have to worry about atomic accesses.
359 #define TS_USEDFPU 0x0001 /* FPU was used by this task
360 this quantum (SMP) */
361 #define TS_COMPAT 0x0002 /* 32bit syscall active */
362 #define TS_POLLING 0x0004 /* true if in idle loop
365 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
371 extern void arch_task_cache_init(void);
372 extern void free_thread_info(struct thread_info *ti);
373 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
374 #define arch_task_cache_init arch_task_cache_init
376 #endif /* _ASM_X86_THREAD_INFO_H */