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>
25 struct task_struct *task; /* main task structure */
26 struct exec_domain *exec_domain; /* execution domain */
27 __u32 flags; /* low level flags */
28 __u32 status; /* thread synchronous flags */
29 __u32 cpu; /* current CPU */
30 int preempt_count; /* 0 => preemptable,
32 mm_segment_t addr_limit;
33 struct restart_block restart_block;
34 void __user *sysenter_return;
36 unsigned long previous_esp; /* ESP of the previous stack in
37 case of nested (IRQ) stacks
39 __u8 supervisor_stack[0];
42 #else /* !__ASSEMBLY__ */
44 #include <asm/asm-offsets.h>
50 #define PREEMPT_ACTIVE 0x10000000
51 #ifdef CONFIG_4KSTACKS
52 #define THREAD_SIZE (4096)
54 #define THREAD_SIZE (8192)
57 #define STACK_WARN (THREAD_SIZE/8)
59 * macros/functions for gaining access to the thread information structure
61 * preempt_count needs to be 1 initially, until the scheduler is functional.
65 #define INIT_THREAD_INFO(tsk) \
68 .exec_domain = &default_exec_domain, \
72 .addr_limit = KERNEL_DS, \
74 .fn = do_no_restart_syscall, \
78 #define init_thread_info (init_thread_union.thread_info)
79 #define init_stack (init_thread_union.stack)
82 /* how to get the current stack pointer from C */
83 register unsigned long current_stack_pointer asm("esp") __used;
85 /* how to get the thread information struct from C */
86 static inline struct thread_info *current_thread_info(void)
88 return (struct thread_info *)
89 (current_stack_pointer & ~(THREAD_SIZE - 1));
92 /* thread information allocation */
93 #ifdef CONFIG_DEBUG_STACK_USAGE
94 #define alloc_thread_info(tsk) ((struct thread_info *) \
95 __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(THREAD_SIZE)))
97 #define alloc_thread_info(tsk) ((struct thread_info *) \
98 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE)))
101 #else /* !__ASSEMBLY__ */
103 /* how to get the thread information struct from ASM */
104 #define GET_THREAD_INFO(reg) \
105 movl $-THREAD_SIZE, reg; \
108 /* use this one if reg already contains %esp */
109 #define GET_THREAD_INFO_WITH_ESP(reg) \
110 andl $-THREAD_SIZE, reg
115 * thread information flags
116 * - these are process state flags that various
117 * assembly files may need to access
118 * - pending work-to-be-done flags are in LSW
119 * - other flags in MSW
121 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
122 #define TIF_SIGPENDING 1 /* signal pending */
123 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
124 #define TIF_SINGLESTEP 3 /* restore singlestep on return to
126 #define TIF_IRET 4 /* return with iret */
127 #define TIF_SYSCALL_EMU 5 /* syscall emulation active */
128 #define TIF_SYSCALL_AUDIT 6 /* syscall auditing active */
129 #define TIF_SECCOMP 7 /* secure computing */
130 #define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */
131 #define TIF_HRTICK_RESCHED 9 /* reprogram hrtick timer */
132 #define TIF_MEMDIE 16
133 #define TIF_DEBUG 17 /* uses debug registers */
134 #define TIF_IO_BITMAP 18 /* uses I/O bitmap */
135 #define TIF_FREEZE 19 /* is freezing for suspend */
136 #define TIF_NOTSC 20 /* TSC is not accessible in userland */
137 #define TIF_FORCED_TF 21 /* true if TF in eflags artificially */
138 #define TIF_DEBUGCTLMSR 22 /* uses thread_struct.debugctlmsr */
139 #define TIF_DS_AREA_MSR 23 /* uses thread_struct.ds_area_msr */
140 #define TIF_BTS_TRACE_TS 24 /* record scheduling event timestamps */
142 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
143 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
144 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
145 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
146 #define _TIF_IRET (1 << TIF_IRET)
147 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
148 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
149 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
150 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
151 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
152 #define _TIF_DEBUG (1 << TIF_DEBUG)
153 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
154 #define _TIF_FREEZE (1 << TIF_FREEZE)
155 #define _TIF_NOTSC (1 << TIF_NOTSC)
156 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
157 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
158 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
159 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
161 /* work to do on interrupt/exception return */
162 #define _TIF_WORK_MASK \
163 (0x0000FFFF & ~(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
164 _TIF_SECCOMP | _TIF_SYSCALL_EMU))
165 /* work to do on any return to u-space */
166 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
168 /* flags to check in __switch_to() */
169 #define _TIF_WORK_CTXSW \
170 (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUGCTLMSR | \
171 _TIF_DS_AREA_MSR | _TIF_BTS_TRACE_TS)
172 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
173 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW | _TIF_DEBUG)
180 * macros/functions for gaining access to the thread information structure
181 * preempt_count needs to be 1 initially, until the scheduler is functional.
184 #define INIT_THREAD_INFO(tsk) \
187 .exec_domain = &default_exec_domain, \
190 .preempt_count = 1, \
191 .addr_limit = KERNEL_DS, \
193 .fn = do_no_restart_syscall, \
197 #define init_thread_info (init_thread_union.thread_info)
198 #define init_stack (init_thread_union.stack)
200 static inline struct thread_info *current_thread_info(void)
202 struct thread_info *ti;
203 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE);
207 /* do not use in interrupt context */
208 static inline struct thread_info *stack_thread_info(void)
210 struct thread_info *ti;
211 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1)));
215 /* thread information allocation */
216 #ifdef CONFIG_DEBUG_STACK_USAGE
217 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO)
219 #define THREAD_FLAGS GFP_KERNEL
222 #define alloc_thread_info(tsk) \
223 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER))
225 #else /* !__ASSEMBLY__ */
227 /* how to get the thread information struct from ASM */
228 #define GET_THREAD_INFO(reg) \
229 movq %gs:pda_kernelstack,reg ; \
230 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg
235 * thread information flags
236 * - these are process state flags that various assembly files
238 * - pending work-to-be-done flags are in LSW
239 * - other flags in MSW
240 * Warning: layout of LSW is hardcoded in entry.S
242 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
243 #define TIF_SIGPENDING 2 /* signal pending */
244 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
245 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
246 #define TIF_IRET 5 /* force IRET */
247 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
248 #define TIF_SECCOMP 8 /* secure computing */
249 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */
250 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */
251 #define TIF_HRTICK_RESCHED 11 /* reprogram hrtick timer */
253 #define TIF_IA32 17 /* 32bit process */
254 #define TIF_FORK 18 /* ret_from_fork */
255 #define TIF_ABI_PENDING 19
256 #define TIF_MEMDIE 20
257 #define TIF_DEBUG 21 /* uses debug registers */
258 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */
259 #define TIF_FREEZE 23 /* is freezing for suspend */
260 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
261 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */
262 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */
263 #define TIF_BTS_TRACE_TS 27 /* record scheduling event timestamps */
264 #define TIF_NOTSC 28 /* TSC is not accessible in userland */
266 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
267 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
268 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
269 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
270 #define _TIF_IRET (1 << TIF_IRET)
271 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
272 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
273 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
274 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY)
275 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
276 #define _TIF_IA32 (1 << TIF_IA32)
277 #define _TIF_FORK (1 << TIF_FORK)
278 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING)
279 #define _TIF_DEBUG (1 << TIF_DEBUG)
280 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
281 #define _TIF_FREEZE (1 << TIF_FREEZE)
282 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
283 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
284 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
285 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
286 #define _TIF_NOTSC (1 << TIF_NOTSC)
288 /* work to do on interrupt/exception return */
289 #define _TIF_WORK_MASK \
291 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP))
292 /* work to do on any return to user space */
293 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
295 #define _TIF_DO_NOTIFY_MASK \
296 (_TIF_SIGPENDING|_TIF_SINGLESTEP|_TIF_MCE_NOTIFY|_TIF_HRTICK_RESCHED)
298 /* flags to check in __switch_to() */
299 #define _TIF_WORK_CTXSW \
300 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS|_TIF_NOTSC)
301 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
302 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG)
304 #define PREEMPT_ACTIVE 0x10000000
309 * Thread-synchronous status.
311 * This is different from the flags in that nobody else
312 * ever touches our thread-synchronous status, so we don't
313 * have to worry about atomic accesses.
315 #define TS_USEDFPU 0x0001 /* FPU was used by this task
316 this quantum (SMP) */
317 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/
318 #define TS_POLLING 0x0004 /* true if in idle loop
321 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
324 extern void arch_task_cache_init(void);
325 extern void free_thread_info(struct thread_info *ti);
326 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
327 #define arch_task_cache_init arch_task_cache_init
329 #endif /* _ASM_X86_THREAD_INFO_H */