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/*
* Mach Operating System
* Copyright (c) 1991,1990 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
#include <mach/machine/asm.h>
#include <i386/i386/proc_reg.h>
#include <i386/i386/i386asm.h>
#include <i386/i386/cpu_number.h>
/*
* Context switch routines for x86_64.
*/
ENTRY(Load_context)
movq S_ARG0,%rcx /* get thread */
movq TH_KERNEL_STACK(%rcx),%rcx /* get kernel stack */
lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%rcx),%rdx
/* point to stack top */
CPU_NUMBER(%eax)
movq %rcx,CX(EXT(active_stacks),%eax) /* store stack address */
movq %rdx,CX(EXT(kernel_stack),%eax) /* store stack top */
/* XXX complete */
movq KSS_ESP(%rcx),%rsp /* switch stacks */
movq KSS_EBP(%rcx),%rbp /* restore registers */
movq KSS_EBX(%rcx),%rbx
movq KSS_R12(%rcx),%r12
movq KSS_R13(%rcx),%r13
movq KSS_R14(%rcx),%r14
movq KSS_R15(%rcx),%r15
xorq %rax,%rax /* return zero (no old thread) */
jmp *KSS_EIP(%rcx) /* resume thread */
/*
* This really only has to save registers
* when there is no explicit continuation.
*/
ENTRY(Switch_context)
CPU_NUMBER(%eax)
movq CX(EXT(active_stacks),%eax),%rcx /* get old kernel stack */
movq %r12,KSS_R12(%rcx) /* save registers */
movq %r13,KSS_R13(%rcx)
movq %r14,KSS_R14(%rcx)
movq %r15,KSS_R15(%rcx)
movq %rbx,KSS_EBX(%rcx)
movq %rbp,KSS_EBP(%rcx)
popq KSS_EIP(%rcx) /* save return PC */
movq %rsp,KSS_ESP(%rcx) /* save SP */
movq S_ARG0,%rax /* get old thread */
movq %rcx,TH_KERNEL_STACK(%rax) /* save old stack */
movq S_ARG1,%rbx /* get continuation */
movq %rbx,TH_SWAP_FUNC(%rax) /* save continuation */
movq S_ARG2,%rsi /* get new thread */
movq TH_KERNEL_STACK(%rsi),%rcx /* get its kernel stack */
lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%rcx),%rbx
/* point to stack top */
CPU_NUMBER(%eax)
movq %rsi,CX(EXT(active_threads),%eax) /* new thread is active */
movq %rcx,CX(EXT(active_stacks),%eax) /* set current stack */
movq %rbx,CX(EXT(kernel_stack),%eax) /* set stack top */
movq KSS_ESP(%rcx),%rsp /* switch stacks */
movq KSS_EBP(%rcx),%rbp /* restore registers */
movq KSS_EBX(%rcx),%rbx
movq KSS_R12(%rcx),%r12
movq KSS_R13(%rcx),%r13
movq KSS_R14(%rcx),%r14
movq KSS_R15(%rcx),%r15
jmp *KSS_EIP(%rcx) /* return old thread */
ENTRY(Thread_continue)
movq %rax,%rdi /* push the thread argument */
xorq %rbp,%rbp /* zero frame pointer */
call *%rbx /* call real continuation */
#if NCPUS > 1
/*
* void switch_to_shutdown_context(thread_t thread,
* void (*routine)(processor_t),
* processor_t processor)
*
* saves the kernel context of the thread,
* switches to the interrupt stack,
* continues the thread (with thread_continue),
* then runs routine on the interrupt stack.
*
* Assumes that the thread is a kernel thread (thus
* has no FPU state)
*/
ENTRY(switch_to_shutdown_context)
ud2
CPU_NUMBER(%eax)
movq EXT(active_stacks)(,%eax,8),%rcx /* get old kernel stack */
movq %r12,KSS_R12(%rcx) /* save registers */
movq %r13,KSS_R13(%rcx)
movq %r14,KSS_R14(%rcx)
movq %r15,KSS_R15(%rcx)
movq %rbx,KSS_EBX(%rcx)
movq %rbp,KSS_EBP(%rcx)
popq KSS_EIP(%rcx) /* save return PC */
movq %rsp,KSS_ESP(%rcx) /* save SP */
movq S_ARG0,%rax /* get old thread */
movq %rcx,TH_KERNEL_STACK(%rax) /* save old stack */
movq $0,TH_SWAP_FUNC(%rax) /* clear continuation */
movq S_ARG1,%rbx /* get routine to run next */
movq S_ARG2,%rsi /* get its argument */
CPU_NUMBER(%eax)
movq EXT(interrupt_stack)(,%eax,8),%rcx /* point to its interrupt stack */
lea INTSTACK_SIZE(%rcx),%rsp /* switch to it (top) */
movq %rax,%rdi /* push thread */
call EXT(thread_dispatch) /* reschedule thread */
movq %rsi,%rdi /* push argument */
call *%rbx /* call routine to run */
hlt /* (should never return) */
#endif /* NCPUS > 1 */
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