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linux/include/asm-sh/thread_info.h
Paul Mundt a6a3113989 sh: Add support for 4K stacks.
This enables support for 4K stacks on SH.

Currently this depends on DEBUG_KERNEL, but likely all boards
will switch to this as the default in the future.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-09-27 18:22:14 +09:00

130 lines
3.6 KiB
C

#ifndef __ASM_SH_THREAD_INFO_H
#define __ASM_SH_THREAD_INFO_H
/* SuperH version
* Copyright (C) 2002 Niibe Yutaka
*
* The copyright of original i386 version is:
*
* Copyright (C) 2002 David Howells (dhowells@redhat.com)
* - Incorporating suggestions made by Linus Torvalds and Dave Miller
*/
#ifdef __KERNEL__
#include <asm/page.h>
#ifndef __ASSEMBLY__
#include <asm/processor.h>
struct thread_info {
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */
__u32 cpu;
int preempt_count; /* 0 => preemptable, <0 => BUG */
mm_segment_t addr_limit; /* thread address space */
struct restart_block restart_block;
unsigned long previous_sp; /* sp of previous stack in case
of nested IRQ stacks */
__u8 supervisor_stack[0];
};
#endif
#define PREEMPT_ACTIVE 0x10000000
#ifdef CONFIG_4KSTACKS
#define THREAD_SIZE (PAGE_SIZE)
#else
#define THREAD_SIZE (PAGE_SIZE * 2)
#endif
#define STACK_WARN (THREAD_SIZE / 8)
/*
* macros/functions for gaining access to the thread information structure
*/
#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 current stack pointer from C */
register unsigned long current_stack_pointer asm("r15") __attribute_used__;
/* how to get the thread information struct from C */
static inline struct thread_info *current_thread_info(void)
{
struct thread_info *ti;
#ifdef CONFIG_CPU_HAS_SR_RB
__asm__("stc r7_bank, %0" : "=r" (ti));
#else
unsigned long __dummy;
__asm__ __volatile__ (
"mov r15, %0\n\t"
"and %1, %0\n\t"
: "=&r" (ti), "=r" (__dummy)
: "1" (~(THREAD_SIZE - 1))
: "memory");
#endif
return ti;
}
/* thread information allocation */
#ifdef CONFIG_DEBUG_STACK_USAGE
#define alloc_thread_info(ti) kzalloc(THREAD_SIZE, GFP_KERNEL)
#else
#define alloc_thread_info(ti) kmalloc(THREAD_SIZE, GFP_KERNEL)
#endif
#define free_thread_info(ti) kfree(ti)
#else /* !__ASSEMBLY__ */
/* how to get the thread information struct from ASM */
#define GET_THREAD_INFO(reg) \
stc r7_bank, 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_RESTORE_SIGMASK 4 /* restore signal mask in do_signal() */
#define TIF_USEDFPU 16 /* FPU was used by this task this quantum (SMP) */
#define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */
#define TIF_MEMDIE 18
#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_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_USEDFPU (1<<TIF_USEDFPU)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_WORK_MASK 0x000000FE /* work to do on interrupt/exception return */
#define _TIF_ALLWORK_MASK 0x000000FF /* work to do on any return to u-space */
#endif /* __KERNEL__ */
#endif /* __ASM_SH_THREAD_INFO_H */