From fd2f80c255acc5edf0cea58053c81f392042bf51 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Fri, 23 Nov 2007 16:23:28 +0000 Subject: [PATCH] [Mini-OS] Fix x86 arch_switch_thread Fix x86 arch_switch_thread by making it pure assembly. There were missing general register clobbers for x86_64, and BP should theorically be clobbered too, but gcc does not believe that, so the only simple safe solution is to use pure assembly. Signed-off-by: Samuel Thibault --- extras/mini-os/arch/x86/x86_32.S | 18 ++++++++++++ extras/mini-os/arch/x86/x86_64.S | 20 +++++++++++++ extras/mini-os/include/sched.h | 1 + extras/mini-os/include/x86/arch_sched.h | 39 ++----------------------- 4 files changed, 41 insertions(+), 37 deletions(-) diff --git a/extras/mini-os/arch/x86/x86_32.S b/extras/mini-os/arch/x86/x86_32.S index 2d359ab44a..09ffeda9ba 100644 --- a/extras/mini-os/arch/x86/x86_32.S +++ b/extras/mini-os/arch/x86/x86_32.S @@ -288,3 +288,21 @@ ENTRY(thread_starter) call *%ebx call exit_thread +ENTRY(__arch_switch_threads) + movl 4(%esp), %ecx /* prev */ + movl 8(%esp), %edx /* next */ + pushl %ebp + pushl %ebx + pushl %esi + pushl %edi + movl %esp, (%ecx) /* save ESP */ + movl (%edx), %esp /* restore ESP */ + movl $1f, 4(%ecx) /* save EIP */ + pushl 4(%edx) /* restore EIP */ + ret +1: + popl %edi + popl %esi + popl %ebx + popl %ebp + ret diff --git a/extras/mini-os/arch/x86/x86_64.S b/extras/mini-os/arch/x86/x86_64.S index 0f85577716..55b17da5f7 100644 --- a/extras/mini-os/arch/x86/x86_64.S +++ b/extras/mini-os/arch/x86/x86_64.S @@ -386,3 +386,23 @@ ENTRY(thread_starter) call exit_thread +ENTRY(__arch_switch_threads) + pushq %rbp + pushq %rbx + pushq %r12 + pushq %r13 + pushq %r14 + pushq %r15 + movq %rsp, (%rdi) /* save ESP */ + movq (%rsi), %rsp /* restore ESP */ + movq $1f, 8(%rdi) /* save EIP */ + pushq 8(%rsi) /* restore EIP */ + ret +1: + popq %r15 + popq %r14 + popq %r13 + popq %r12 + popq %rbx + popq %rbp + ret diff --git a/extras/mini-os/include/sched.h b/extras/mini-os/include/sched.h index 1425d0943c..9f209f195d 100644 --- a/extras/mini-os/include/sched.h +++ b/extras/mini-os/include/sched.h @@ -10,6 +10,7 @@ struct thread char *name; char *stack; #if !defined(__ia64__) + /* keep in that order */ unsigned long sp; /* Stack pointer */ unsigned long ip; /* Instruction pointer */ #else /* !defined(__ia64__) */ diff --git a/extras/mini-os/include/x86/arch_sched.h b/extras/mini-os/include/x86/arch_sched.h index 7bf0036fac..35a4344efd 100644 --- a/extras/mini-os/include/x86/arch_sched.h +++ b/extras/mini-os/include/x86/arch_sched.h @@ -15,44 +15,9 @@ static inline struct thread* get_current(void) return *current; } -#ifdef __i386__ -#define arch_switch_threads(prev, next) do { \ - unsigned long esi,edi; \ - __asm__ __volatile__("pushfl\n\t" \ - "pushl %%ebp\n\t" \ - "movl %%esp,%0\n\t" /* save ESP */ \ - "movl %4,%%esp\n\t" /* restore ESP */ \ - "movl $1f,%1\n\t" /* save EIP */ \ - "pushl %5\n\t" /* restore EIP */ \ - "ret\n\t" \ - "1:\t" \ - "popl %%ebp\n\t" \ - "popfl" \ - :"=m" (prev->sp),"=m" (prev->ip), \ - "=S" (esi),"=D" (edi) \ - :"m" (next->sp),"m" (next->ip), \ - "2" (prev), "d" (next)); \ -} while (0) -#elif __x86_64__ -#define arch_switch_threads(prev, next) do { \ - unsigned long rsi,rdi; \ - __asm__ __volatile__("pushfq\n\t" \ - "pushq %%rbp\n\t" \ - "movq %%rsp,%0\n\t" /* save RSP */ \ - "movq %4,%%rsp\n\t" /* restore RSP */ \ - "movq $1f,%1\n\t" /* save RIP */ \ - "pushq %5\n\t" /* restore RIP */ \ - "ret\n\t" \ - "1:\t" \ - "popq %%rbp\n\t" \ - "popfq" \ - :"=m" (prev->sp),"=m" (prev->ip), \ - "=S" (rsi),"=D" (rdi) \ - :"m" (next->sp),"m" (next->ip), \ - "2" (prev), "d" (next)); \ -} while (0) -#endif +extern void __arch_switch_threads(unsigned long *prevctx, unsigned long *nextctx); +#define arch_switch_threads(prev,next) __arch_switch_threads(&(prev)->sp, &(next)->sp) -- 2.30.2