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linux/arch/mips/kernel/entry.S
Thiemo Seufer b59a9504cb De-optimize and decomplicate the spurious interrupt handler.
Signed-off-by: Thiemo Seufer <ths@networkno.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29 19:30:15 +01:00

153 lines
3.4 KiB
ArmAsm

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2001 MIPS Technologies, Inc.
*/
#include <linux/config.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/isadep.h>
#include <asm/thread_info.h>
#include <asm/war.h>
#ifdef CONFIG_PREEMPT
.macro preempt_stop reg=t0
.endm
#else
.macro preempt_stop reg=t0
local_irq_disable \reg
.endm
#define resume_kernel restore_all
#endif
.text
.align 5
FEXPORT(ret_from_exception)
preempt_stop
FEXPORT(ret_from_irq)
LONG_L t0, PT_STATUS(sp) # returning to kernel mode?
andi t0, t0, KU_USER
beqz t0, resume_kernel
FEXPORT(resume_userspace)
local_irq_disable t0 # make sure we dont miss an
# interrupt setting need_resched
# between sampling and return
LONG_L a2, TI_FLAGS($28) # current->work
andi a2, _TIF_WORK_MASK # (ignoring syscall_trace)
bnez a2, work_pending
j restore_all
#ifdef CONFIG_PREEMPT
ENTRY(resume_kernel)
lw t0, TI_PRE_COUNT($28)
bnez t0, restore_all
need_resched:
LONG_L t0, TI_FLAGS($28)
andi t1, t0, _TIF_NEED_RESCHED
beqz t1, restore_all
LONG_L t0, PT_STATUS(sp) # Interrupts off?
andi t0, 1
beqz t0, restore_all
li t0, PREEMPT_ACTIVE
sw t0, TI_PRE_COUNT($28)
local_irq_enable t0
jal schedule
sw zero, TI_PRE_COUNT($28)
local_irq_disable t0
b need_resched
#endif
FEXPORT(ret_from_fork)
jal schedule_tail # a0 = task_t *prev
FEXPORT(syscall_exit)
local_irq_disable # make sure need_resched and
# signals dont change between
# sampling and return
LONG_L a2, TI_FLAGS($28) # current->work
li t0, _TIF_ALLWORK_MASK
and t0, a2, t0
bnez t0, syscall_exit_work
FEXPORT(restore_all) # restore full frame
.set noat
RESTORE_TEMP
RESTORE_AT
RESTORE_STATIC
FEXPORT(restore_partial) # restore partial frame
RESTORE_SOME
RESTORE_SP_AND_RET
.set at
FEXPORT(work_pending)
andi t0, a2, _TIF_NEED_RESCHED
beqz t0, work_notifysig
work_resched:
jal schedule
local_irq_disable t0 # make sure need_resched and
# signals dont change between
# sampling and return
LONG_L a2, TI_FLAGS($28)
andi t0, a2, _TIF_WORK_MASK # is there any work to be done
# other than syscall tracing?
beqz t0, restore_all
andi t0, a2, _TIF_NEED_RESCHED
bnez t0, work_resched
work_notifysig: # deal with pending signals and
# notify-resume requests
move a0, sp
li a1, 0
jal do_notify_resume # a2 already loaded
j restore_all
FEXPORT(syscall_exit_work_partial)
SAVE_STATIC
FEXPORT(syscall_exit_work)
LONG_L t0, TI_FLAGS($28)
li t1, _TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT
and t0, t1
beqz t0, work_pending # trace bit is set
local_irq_enable # could let do_syscall_trace()
# call schedule() instead
move a0, sp
li a1, 1
jal do_syscall_trace
b resume_userspace
/*
* Common spurious interrupt handler.
*/
LEAF(spurious_interrupt)
/*
* Someone tried to fool us by sending an interrupt but we
* couldn't find a cause for it.
*/
PTR_LA t1, irq_err_count
#ifdef CONFIG_SMP
1: ll t0, (t1)
addiu t0, 1
sc t0, (t1)
#if R10000_LLSC_WAR
beqzl t0, 1b
#else
beqz t0, 1b
#endif
#else
lw t0, (t1)
addiu t0, 1
sw t0, (t1)
#endif
j ret_from_irq
END(spurious_interrupt)