/* thread_info.h: x86_64 low-level thread information * * Copyright (C) 2002 David Howells (dhowells@redhat.com) * - Incorporating suggestions made by Linus Torvalds and Dave Miller */ #ifndef _ASM_THREAD_INFO_H #define _ASM_THREAD_INFO_H #ifdef __KERNEL__ #include #include #include /* * low level task data that entry.S needs immediate access to * - this struct should fit entirely inside of one cache line * - this struct shares the supervisor stack pages */ #ifndef __ASSEMBLY__ struct task_struct; struct exec_domain; #include struct thread_info { struct task_struct *task; /* main task structure */ struct exec_domain *exec_domain; /* execution domain */ __u32 flags; /* low level flags */ __u32 status; /* thread synchronous flags */ __u32 cpu; /* current CPU */ int preempt_count; /* 0 => preemptable, <0 => BUG */ mm_segment_t addr_limit; struct restart_block restart_block; }; #endif /* * macros/functions for gaining access to the thread information structure * preempt_count needs to be 1 initially, until the scheduler is functional. */ #ifndef __ASSEMBLY__ #define INIT_THREAD_INFO(tsk) \ { \ .task = &tsk, \ .exec_domain = &default_exec_domain, \ .flags = 0, \ .cpu = 0, \ .preempt_count = 1, \ .addr_limit = KERNEL_DS, \ .restart_block = { \ .fn = do_no_restart_syscall, \ }, \ } #define init_thread_info (init_thread_union.thread_info) #define init_stack (init_thread_union.stack) #if !defined(__VMKLNX__) static inline struct thread_info *current_thread_info(void) { struct thread_info *ti; ti = (void *)(read_pda(kernelstack) + PDA_STACKOFFSET - THREAD_SIZE); return ti; } /* do not use in interrupt context */ static inline struct thread_info *stack_thread_info(void) { struct thread_info *ti; __asm__("andq %%rsp,%0; ":"=r" (ti) : "0" (~(THREAD_SIZE - 1))); return ti; } /* thread information allocation */ #ifdef CONFIG_DEBUG_STACK_USAGE #define alloc_thread_info(tsk) \ ({ \ struct thread_info *ret; \ \ ret = ((struct thread_info *) __get_free_pages(GFP_KERNEL,THREAD_ORDER)); \ if (ret) \ memset(ret, 0, THREAD_SIZE); \ ret; \ }) #else #define alloc_thread_info(tsk) \ ((struct thread_info *) __get_free_pages(GFP_KERNEL,THREAD_ORDER)) #endif #define free_thread_info(ti) free_pages((unsigned long) (ti), THREAD_ORDER) #else /* !__ASSEMBLY__ */ /* how to get the thread information struct from ASM */ #define GET_THREAD_INFO(reg) \ movq %gs:pda_kernelstack,reg ; \ subq $(THREAD_SIZE-PDA_STACKOFFSET),reg #endif /* * thread information flags * - these are process state flags that various assembly files may need to access * - pending work-to-be-done flags are in LSW * - other flags in MSW * Warning: layout of LSW is hardcoded in entry.S */ #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_NOTIFY_RESUME 1 /* resumption notification requested */ #define TIF_SIGPENDING 2 /* signal pending */ #define TIF_NEED_RESCHED 3 /* rescheduling necessary */ #define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/ #define TIF_IRET 5 /* force IRET */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ #define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */ /* 16 free */ #define TIF_IA32 17 /* 32bit process */ #define TIF_FORK 18 /* ret_from_fork */ #define TIF_ABI_PENDING 19 #define TIF_MEMDIE 20 #define TIF_FORCED_TF 21 /* true if TF in eflags artificially */ #define _TIF_SYSCALL_TRACE (1<thread_info->status & TS_POLLING) #endif /* __KERNEL__ */ #endif /* !defined(__VMKLNX__) */ #endif /* _ASM_THREAD_INFO_H */