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];
43 #define INIT_THREAD_INFO(tsk) \
46 .exec_domain = &default_exec_domain, \
50 .addr_limit = KERNEL_DS, \
52 .fn = do_no_restart_syscall, \
56 #define init_thread_info (init_thread_union.thread_info)
57 #define init_stack (init_thread_union.stack)
59 #else /* !__ASSEMBLY__ */
61 #include <asm/asm-offsets.h>
65 #define PREEMPT_ACTIVE 0x10000000
69 #ifdef CONFIG_4KSTACKS
70 #define THREAD_SIZE (4096)
72 #define THREAD_SIZE (8192)
75 #define STACK_WARN (THREAD_SIZE/8)
77 * macros/functions for gaining access to the thread information structure
79 * preempt_count needs to be 1 initially, until the scheduler is functional.
84 /* how to get the current stack pointer from C */
85 register unsigned long current_stack_pointer asm("esp") __used;
87 /* how to get the thread information struct from C */
88 static inline struct thread_info *current_thread_info(void)
90 return (struct thread_info *)
91 (current_stack_pointer & ~(THREAD_SIZE - 1));
94 /* thread information allocation */
95 #ifdef CONFIG_DEBUG_STACK_USAGE
96 #define alloc_thread_info(tsk) ((struct thread_info *) \
97 __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(THREAD_SIZE)))
99 #define alloc_thread_info(tsk) ((struct thread_info *) \
100 __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE)))
103 #else /* !__ASSEMBLY__ */
105 /* how to get the thread information struct from ASM */
106 #define GET_THREAD_INFO(reg) \
107 movl $-THREAD_SIZE, reg; \
110 /* use this one if reg already contains %esp */
111 #define GET_THREAD_INFO_WITH_ESP(reg) \
112 andl $-THREAD_SIZE, reg
117 * thread information flags
118 * - these are process state flags that various
119 * assembly files may need to access
120 * - pending work-to-be-done flags are in LSW
121 * - other flags in MSW
123 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
124 #define TIF_SIGPENDING 1 /* signal pending */
125 #define TIF_NEED_RESCHED 2 /* rescheduling necessary */
126 #define TIF_SINGLESTEP 3 /* restore singlestep on return to
128 #define TIF_IRET 4 /* return with iret */
129 #define TIF_SYSCALL_EMU 5 /* syscall emulation active */
130 #define TIF_SYSCALL_AUDIT 6 /* syscall auditing active */
131 #define TIF_SECCOMP 7 /* secure computing */
132 #define TIF_RESTORE_SIGMASK 8 /* restore signal mask in do_signal() */
133 #define TIF_HRTICK_RESCHED 9 /* reprogram hrtick timer */
134 #define TIF_MEMDIE 16
135 #define TIF_DEBUG 17 /* uses debug registers */
136 #define TIF_IO_BITMAP 18 /* uses I/O bitmap */
137 #define TIF_FREEZE 19 /* is freezing for suspend */
138 #define TIF_NOTSC 20 /* TSC is not accessible in userland */
139 #define TIF_FORCED_TF 21 /* true if TF in eflags artificially */
140 #define TIF_DEBUGCTLMSR 22 /* uses thread_struct.debugctlmsr */
141 #define TIF_DS_AREA_MSR 23 /* uses thread_struct.ds_area_msr */
142 #define TIF_BTS_TRACE_TS 24 /* record scheduling event timestamps */
144 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
145 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
146 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
147 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
148 #define _TIF_IRET (1 << TIF_IRET)
149 #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
150 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
151 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
152 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
153 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
154 #define _TIF_DEBUG (1 << TIF_DEBUG)
155 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
156 #define _TIF_FREEZE (1 << TIF_FREEZE)
157 #define _TIF_NOTSC (1 << TIF_NOTSC)
158 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
159 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
160 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
161 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
163 /* work to do on interrupt/exception return */
164 #define _TIF_WORK_MASK \
165 (0x0000FFFF & ~(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
166 _TIF_SECCOMP | _TIF_SYSCALL_EMU))
167 /* work to do on any return to u-space */
168 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
170 /* flags to check in __switch_to() */
171 #define _TIF_WORK_CTXSW \
172 (_TIF_IO_BITMAP | _TIF_NOTSC | _TIF_DEBUGCTLMSR | \
173 _TIF_DS_AREA_MSR | _TIF_BTS_TRACE_TS)
174 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
175 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW | _TIF_DEBUG)
182 * macros/functions for gaining access to the thread information structure
183 * preempt_count needs to be 1 initially, until the scheduler is functional.
186 static inline struct thread_info *current_thread_info(void)
188 struct thread_info *ti;
189 ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE);
193 /* do not use in interrupt context */
194 static inline struct thread_info *stack_thread_info(void)
196 struct thread_info *ti;
197 asm("andq %%rsp,%0; " : "=r" (ti) : "0" (~(THREAD_SIZE - 1)));
201 /* thread information allocation */
202 #ifdef CONFIG_DEBUG_STACK_USAGE
203 #define THREAD_FLAGS (GFP_KERNEL | __GFP_ZERO)
205 #define THREAD_FLAGS GFP_KERNEL
208 #define alloc_thread_info(tsk) \
209 ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER))
211 #else /* !__ASSEMBLY__ */
213 /* how to get the thread information struct from ASM */
214 #define GET_THREAD_INFO(reg) \
215 movq %gs:pda_kernelstack,reg ; \
216 subq $(THREAD_SIZE-PDA_STACKOFFSET),reg
221 * thread information flags
222 * - these are process state flags that various assembly files
224 * - pending work-to-be-done flags are in LSW
225 * - other flags in MSW
226 * Warning: layout of LSW is hardcoded in entry.S
228 #define TIF_SYSCALL_TRACE 0 /* syscall trace active */
229 #define TIF_SIGPENDING 2 /* signal pending */
230 #define TIF_NEED_RESCHED 3 /* rescheduling necessary */
231 #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
232 #define TIF_IRET 5 /* force IRET */
233 #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
234 #define TIF_SECCOMP 8 /* secure computing */
235 #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */
236 #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */
237 #define TIF_HRTICK_RESCHED 11 /* reprogram hrtick timer */
239 #define TIF_IA32 17 /* 32bit process */
240 #define TIF_FORK 18 /* ret_from_fork */
241 #define TIF_ABI_PENDING 19
242 #define TIF_MEMDIE 20
243 #define TIF_DEBUG 21 /* uses debug registers */
244 #define TIF_IO_BITMAP 22 /* uses I/O bitmap */
245 #define TIF_FREEZE 23 /* is freezing for suspend */
246 #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
247 #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */
248 #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */
249 #define TIF_BTS_TRACE_TS 27 /* record scheduling event timestamps */
250 #define TIF_NOTSC 28 /* TSC is not accessible in userland */
252 #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
253 #define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
254 #define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
255 #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
256 #define _TIF_IRET (1 << TIF_IRET)
257 #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
258 #define _TIF_SECCOMP (1 << TIF_SECCOMP)
259 #define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
260 #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY)
261 #define _TIF_HRTICK_RESCHED (1 << TIF_HRTICK_RESCHED)
262 #define _TIF_IA32 (1 << TIF_IA32)
263 #define _TIF_FORK (1 << TIF_FORK)
264 #define _TIF_ABI_PENDING (1 << TIF_ABI_PENDING)
265 #define _TIF_DEBUG (1 << TIF_DEBUG)
266 #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)
267 #define _TIF_FREEZE (1 << TIF_FREEZE)
268 #define _TIF_FORCED_TF (1 << TIF_FORCED_TF)
269 #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR)
270 #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR)
271 #define _TIF_BTS_TRACE_TS (1 << TIF_BTS_TRACE_TS)
272 #define _TIF_NOTSC (1 << TIF_NOTSC)
274 /* work to do on interrupt/exception return */
275 #define _TIF_WORK_MASK \
277 ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP))
278 /* work to do on any return to user space */
279 #define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP)
281 #define _TIF_DO_NOTIFY_MASK \
282 (_TIF_SIGPENDING|_TIF_SINGLESTEP|_TIF_MCE_NOTIFY|_TIF_HRTICK_RESCHED)
284 /* flags to check in __switch_to() */
285 #define _TIF_WORK_CTXSW \
286 (_TIF_IO_BITMAP|_TIF_DEBUGCTLMSR|_TIF_DS_AREA_MSR|_TIF_BTS_TRACE_TS|_TIF_NOTSC)
287 #define _TIF_WORK_CTXSW_PREV _TIF_WORK_CTXSW
288 #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW|_TIF_DEBUG)
293 * Thread-synchronous status.
295 * This is different from the flags in that nobody else
296 * ever touches our thread-synchronous status, so we don't
297 * have to worry about atomic accesses.
299 #define TS_USEDFPU 0x0001 /* FPU was used by this task
300 this quantum (SMP) */
301 #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/
302 #define TS_POLLING 0x0004 /* true if in idle loop
305 #define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
308 extern void arch_task_cache_init(void);
309 extern void free_thread_info(struct thread_info *ti);
310 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
311 #define arch_task_cache_init arch_task_cache_init
313 #endif /* _ASM_X86_THREAD_INFO_H */