/* MN10300 task switching definitions * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public Licence * as published by the Free Software Foundation; either version * 2 of the Licence, or (at your option) any later version. */ #ifndef _ASM_SWITCH_TO_H #define _ASM_SWITCH_TO_H #include <asm/barrier.h> struct task_struct; struct thread_struct; #if defined([31mCONFIG_FPU[0m) && !defined([31mCONFIG_LAZY_SAVE_FPU[0m) struct fpu_state_struct; extern asmlinkage void fpu_save(struct fpu_state_struct *); #define switch_fpu(prev, next) \ do { \ if ((prev)->thread.fpu_flags & THREAD_HAS_FPU) { \ (prev)->thread.fpu_flags &= ~THREAD_HAS_FPU; \ (prev)->thread.uregs->epsw &= ~EPSW_FE; \ fpu_save(&(prev)->thread.fpu_state); \ } \ } while (0) #else #define switch_fpu(prev, next) do {} while (0) #endif /* context switching is now performed out-of-line in switch_to.S */ extern asmlinkage struct task_struct *__switch_to(struct thread_struct *prev, struct thread_struct *next, struct task_struct *prev_task); #define switch_to(prev, next, last) \ do { \ switch_fpu(prev, next); \ current->thread.wchan = (u_long) __builtin_return_address(0); \ (last) = __switch_to(&(prev)->thread, &(next)->thread, (prev)); \ mb(); \ current->thread.wchan = 0; \ } while (0) #endif /* _ASM_SWITCH_TO_H */ |