Fix x86 arch_switch_thread
PATCH 1/1 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 <[email protected]>
extras/mini-os/arch/x86/x86_32.S +18 -0
@@ -283,3 +283,21 @@ 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
extras/mini-os/arch/x86/x86_64.S +20 -0
@@ -382,3 +378,23 @@ 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
extras/mini-os/include/x86/arch_sched.h +2 -37
@@ -11,44 +4,9 @@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)
extras/mini-os/include/sched.h +1 -0
@@ -10,6 +10,7 @@ struct threadchar *name;char *stack;#if !defined(__ia64__) +/* keep in that order */ unsigned long sp;/* Stack pointer */ unsigned long ip;/* Instruction pointer */ #else /* !defined(__ia64__) */