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Diffstat (limited to 'include/asm-i386/thread_info.h')
| -rw-r--r-- | include/asm-i386/thread_info.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/include/asm-i386/thread_info.h b/include/asm-i386/thread_info.h new file mode 100644 index 000000000000..2cd57271801d --- /dev/null +++ b/include/asm-i386/thread_info.h @@ -0,0 +1,174 @@ +/* thread_info.h: i386 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 <linux/config.h> +#include <linux/compiler.h> +#include <asm/page.h> + +#ifndef __ASSEMBLY__ +#include <asm/processor.h> +#endif + +/* + * 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 + * - if the contents of this structure are changed, the assembly constants must also be changed + */ +#ifndef __ASSEMBLY__ + +struct thread_info { + struct task_struct *task; /* main task structure */ + struct exec_domain *exec_domain; /* execution domain */ + unsigned long flags; /* low level flags */ + unsigned long status; /* thread-synchronous flags */ + __u32 cpu; /* current CPU */ + __s32 preempt_count; /* 0 => preemptable, <0 => BUG */ + + + mm_segment_t addr_limit; /* thread address space: + 0-0xBFFFFFFF for user-thead + 0-0xFFFFFFFF for kernel-thread + */ + struct restart_block restart_block; + + unsigned long previous_esp; /* ESP of the previous stack in case + of nested (IRQ) stacks + */ + __u8 supervisor_stack[0]; +}; + +#else /* !__ASSEMBLY__ */ + +#include <asm/asm_offsets.h> + +#endif + +#define PREEMPT_ACTIVE 0x10000000 +#ifdef CONFIG_4KSTACKS +#define THREAD_SIZE (4096) +#else +#define THREAD_SIZE (8192) +#endif + +#define STACK_WARN (THREAD_SIZE/8) +/* + * 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) + + +/* how to get the thread information struct from C */ +static inline struct thread_info *current_thread_info(void) +{ + struct thread_info *ti; + __asm__("andl %%esp,%0; ":"=r" (ti) : "0" (~(THREAD_SIZE - 1))); + return ti; +} + +/* how to get the current stack pointer from C */ +register unsigned long current_stack_pointer asm("esp") __attribute_used__; + +/* thread information allocation */ +#ifdef CONFIG_DEBUG_STACK_USAGE +#define alloc_thread_info(tsk) \ + ({ \ + struct thread_info *ret; \ + \ + ret = kmalloc(THREAD_SIZE, GFP_KERNEL); \ + if (ret) \ + memset(ret, 0, THREAD_SIZE); \ + ret; \ + }) +#else +#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL) +#endif + +#define free_thread_info(info) kfree(info) +#define get_thread_info(ti) get_task_struct((ti)->task) +#define put_thread_info(ti) put_task_struct((ti)->task) + +#else /* !__ASSEMBLY__ */ + +/* how to get the thread information struct from ASM */ +#define GET_THREAD_INFO(reg) \ + movl $-THREAD_SIZE, reg; \ + andl %esp, reg + +/* use this one if reg already contains %esp */ +#define GET_THREAD_INFO_WITH_ESP(reg) \ + andl $-THREAD_SIZE, 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 + */ +#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 /* restore singlestep on return to user mode */ +#define TIF_IRET 5 /* return with iret */ +#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ +#define TIF_SECCOMP 8 /* secure computing */ +#define TIF_POLLING_NRFLAG 16 /* true if poll_idle() is polling TIF_NEED_RESCHED */ +#define TIF_MEMDIE 17 + +#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) +#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME) +#define _TIF_SIGPENDING (1<<TIF_SIGPENDING) +#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED) +#define _TIF_SINGLESTEP (1<<TIF_SINGLESTEP) +#define _TIF_IRET (1<<TIF_IRET) +#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT) +#define _TIF_SECCOMP (1<<TIF_SECCOMP) +#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) + +/* work to do on interrupt/exception return */ +#define _TIF_WORK_MASK \ + (0x0000FFFF & ~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP|_TIF_SECCOMP)) +/* work to do on any return to u-space */ +#define _TIF_ALLWORK_MASK (0x0000FFFF & ~_TIF_SECCOMP) + +/* + * Thread-synchronous status. + * + * This is different from the flags in that nobody else + * ever touches our thread-synchronous status, so we don't + * have to worry about atomic accesses. + */ +#define TS_USEDFPU 0x0001 /* FPU was used by this task this quantum (SMP) */ + +#endif /* __KERNEL__ */ + +#endif /* _ASM_THREAD_INFO_H */ |