9cc719ab3f
Due to the slightly odd way that new threads and processes start execution when scheduled for the very first time they were bypassing the required disable_msa call. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
127 lines
3.9 KiB
C
127 lines
3.9 KiB
C
/*
|
|
* 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, 95, 96, 97, 98, 99, 2003, 06 by Ralf Baechle
|
|
* Copyright (C) 1996 by Paul M. Antoine
|
|
* Copyright (C) 1999 Silicon Graphics
|
|
* Kevin D. Kissell, kevink@mips.org and Carsten Langgaard, carstenl@mips.com
|
|
* Copyright (C) 2000 MIPS Technologies, Inc.
|
|
*/
|
|
#ifndef _ASM_SWITCH_TO_H
|
|
#define _ASM_SWITCH_TO_H
|
|
|
|
#include <asm/cpu-features.h>
|
|
#include <asm/watch.h>
|
|
#include <asm/dsp.h>
|
|
#include <asm/cop2.h>
|
|
#include <asm/msa.h>
|
|
|
|
struct task_struct;
|
|
|
|
enum {
|
|
FP_SAVE_NONE = 0,
|
|
FP_SAVE_VECTOR = -1,
|
|
FP_SAVE_SCALAR = 1,
|
|
};
|
|
|
|
/**
|
|
* resume - resume execution of a task
|
|
* @prev: The task previously executed.
|
|
* @next: The task to begin executing.
|
|
* @next_ti: task_thread_info(next).
|
|
* @fp_save: Which, if any, FP context to save for prev.
|
|
*
|
|
* This function is used whilst scheduling to save the context of prev & load
|
|
* the context of next. Returns prev.
|
|
*/
|
|
extern asmlinkage struct task_struct *resume(struct task_struct *prev,
|
|
struct task_struct *next, struct thread_info *next_ti,
|
|
s32 fp_save);
|
|
|
|
extern unsigned int ll_bit;
|
|
extern struct task_struct *ll_task;
|
|
|
|
#ifdef CONFIG_MIPS_MT_FPAFF
|
|
|
|
/*
|
|
* Handle the scheduler resume end of FPU affinity management. We do this
|
|
* inline to try to keep the overhead down. If we have been forced to run on
|
|
* a "CPU" with an FPU because of a previous high level of FP computation,
|
|
* but did not actually use the FPU during the most recent time-slice (CU1
|
|
* isn't set), we undo the restriction on cpus_allowed.
|
|
*
|
|
* We're not calling set_cpus_allowed() here, because we have no need to
|
|
* force prompt migration - we're already switching the current CPU to a
|
|
* different thread.
|
|
*/
|
|
|
|
#define __mips_mt_fpaff_switch_to(prev) \
|
|
do { \
|
|
struct thread_info *__prev_ti = task_thread_info(prev); \
|
|
\
|
|
if (cpu_has_fpu && \
|
|
test_ti_thread_flag(__prev_ti, TIF_FPUBOUND) && \
|
|
(!(KSTK_STATUS(prev) & ST0_CU1))) { \
|
|
clear_ti_thread_flag(__prev_ti, TIF_FPUBOUND); \
|
|
prev->cpus_allowed = prev->thread.user_cpus_allowed; \
|
|
} \
|
|
next->thread.emulated_fp = 0; \
|
|
} while(0)
|
|
|
|
#else
|
|
#define __mips_mt_fpaff_switch_to(prev) do { (void) (prev); } while (0)
|
|
#endif
|
|
|
|
#define __clear_software_ll_bit() \
|
|
do { if (cpu_has_rw_llb) { \
|
|
write_c0_lladdr(0); \
|
|
} else { \
|
|
if (!__builtin_constant_p(cpu_has_llsc) || !cpu_has_llsc)\
|
|
ll_bit = 0; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define switch_to(prev, next, last) \
|
|
do { \
|
|
u32 __c0_stat; \
|
|
s32 __fpsave = FP_SAVE_NONE; \
|
|
__mips_mt_fpaff_switch_to(prev); \
|
|
if (cpu_has_dsp) \
|
|
__save_dsp(prev); \
|
|
if (cop2_present && (KSTK_STATUS(prev) & ST0_CU2)) { \
|
|
if (cop2_lazy_restore) \
|
|
KSTK_STATUS(prev) &= ~ST0_CU2; \
|
|
__c0_stat = read_c0_status(); \
|
|
write_c0_status(__c0_stat | ST0_CU2); \
|
|
cop2_save(prev); \
|
|
write_c0_status(__c0_stat & ~ST0_CU2); \
|
|
} \
|
|
__clear_software_ll_bit(); \
|
|
if (test_and_clear_tsk_thread_flag(prev, TIF_USEDFPU)) \
|
|
__fpsave = FP_SAVE_SCALAR; \
|
|
if (test_and_clear_tsk_thread_flag(prev, TIF_USEDMSA)) \
|
|
__fpsave = FP_SAVE_VECTOR; \
|
|
(last) = resume(prev, next, task_thread_info(next), __fpsave); \
|
|
} while (0)
|
|
|
|
#define finish_arch_switch(prev) \
|
|
do { \
|
|
u32 __c0_stat; \
|
|
if (cop2_present && !cop2_lazy_restore && \
|
|
(KSTK_STATUS(current) & ST0_CU2)) { \
|
|
__c0_stat = read_c0_status(); \
|
|
write_c0_status(__c0_stat | ST0_CU2); \
|
|
cop2_restore(current); \
|
|
write_c0_status(__c0_stat & ~ST0_CU2); \
|
|
} \
|
|
if (cpu_has_dsp) \
|
|
__restore_dsp(current); \
|
|
if (cpu_has_userlocal) \
|
|
write_c0_userlocal(current_thread_info()->tp_value); \
|
|
__restore_watch(); \
|
|
disable_msa(); \
|
|
} while (0)
|
|
|
|
#endif /* _ASM_SWITCH_TO_H */
|