kernel-ark/include/asm-blackfin/thread_info.h
Robert P. J. Day 18628e4375 [Blackfin] arch: Clean up the definition and correct the commentary for current_thread_info().
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
2008-04-24 09:02:00 +08:00

139 lines
4.2 KiB
C

/*
* File: include/asm-blackfin/thread_info.h
* Based on: include/asm-m68knommu/thread_info.h
* Author: LG Soft India
* Copyright (C) 2004-2005 Analog Devices Inc.
* Created: Tue Sep 21 2004
* Description: Blackfin low-level thread information
* Modified:
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING.
* If not, write to the Free Software Foundation,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _ASM_THREAD_INFO_H
#define _ASM_THREAD_INFO_H
#include <asm/page.h>
#include <asm/entry.h>
#include <asm/l1layout.h>
#include <linux/compiler.h>
#ifdef __KERNEL__
/* Thread Align Mask to reach to the top of the stack
* for any process
*/
#define ALIGN_PAGE_MASK 0xffffe000
/*
* Size of kernel stack for each process. This must be a power of 2...
*/
#define THREAD_SIZE 8192 /* 2 pages */
#ifndef __ASSEMBLY__
typedef unsigned long mm_segment_t;
/*
* low level task data.
* If you change this, change the TI_* offsets below to match.
*/
struct thread_info {
struct task_struct *task; /* main task structure */
struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */
int cpu; /* cpu we're on */
int preempt_count; /* 0 => preemptable, <0 => BUG */
mm_segment_t addr_limit; /* address limit */
struct restart_block restart_block;
struct l1_scratch_task_info l1_task_info;
};
/*
* macros/functions for gaining access to the thread information structure
*/
#define INIT_THREAD_INFO(tsk) \
{ \
.task = &tsk, \
.exec_domain = &default_exec_domain, \
.flags = 0, \
.cpu = 0, \
.preempt_count = 1, \
.restart_block = { \
.fn = do_no_restart_syscall, \
}, \
}
#define init_thread_info (init_thread_union.thread_info)
#define init_stack (init_thread_union.stack)
/* Given a task stack pointer, you can find its corresponding
* thread_info structure just by masking it to the THREAD_SIZE
* boundary (currently 8K as you can see above).
*/
__attribute_const__
static inline struct thread_info *current_thread_info(void)
{
struct thread_info *ti;
__asm__("%0 = sp;": "=&d"(ti):
);
return (struct thread_info *)((long)ti & ~((long)THREAD_SIZE-1));
}
/* thread information allocation */
#define alloc_thread_info(tsk) ((struct thread_info *) \
__get_free_pages(GFP_KERNEL, 1))
#define free_thread_info(ti) free_pages((unsigned long) (ti), 1)
#endif /* __ASSEMBLY__ */
/*
* Offsets in thread_info structure, used in assembly code
*/
#define TI_TASK 0
#define TI_EXECDOMAIN 4
#define TI_FLAGS 8
#define TI_CPU 12
#define TI_PREEMPT 16
#define PREEMPT_ACTIVE 0x4000000
/*
* thread information flag bit numbers
*/
#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
#define TIF_SIGPENDING 1 /* signal pending */
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
#define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling
TIF_NEED_RESCHED */
#define TIF_MEMDIE 4
#define TIF_RESTORE_SIGMASK 5 /* restore signal mask in do_signal() */
#define TIF_FREEZE 6 /* is freezing for suspend */
/* as above, but as bit values */
#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_WORK_MASK 0x0000FFFE /* work to do on interrupt/exception return */
#endif /* __KERNEL__ */
#endif /* _ASM_THREAD_INFO_H */