X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Fswitch.S;h=feca86cd16d02e3d6f31d1dde25cff379c0861a4;hb=a03618133f7df0954802a470a4bee7674f7aed45;hp=16c95180c2d36ec4ebe95bc02d775af26c8a0d4c;hpb=b190a933e6fc9048fbea90d626cffb0fb7ef21cc;p=pintos-anon diff --git a/src/threads/switch.S b/src/threads/switch.S index 16c9518..feca86c 100644 --- a/src/threads/switch.S +++ b/src/threads/switch.S @@ -12,15 +12,17 @@ #### restore the registers. As part of switching stacks we record the #### current stack pointer in CUR's thread structure. -.globl switch_threads +.globl switch_threads +.func switch_threads switch_threads: # Save caller's register state. # # Note that the SVR4 ABI allows us to destroy %eax, %ecx, %edx, # but requires us to preserve %ebx, %ebp, %esi, %edi. See - # [SV-ABI-386] pages 3-11 and 3-12 for details. + # [SysV-ABI-386] pages 3-11 and 3-12 for details. # - # This stack frame must match the one set up by thread_create(). + # This stack frame must match the one set up by thread_create() + # in size. pushl %ebx pushl %ebp pushl %esi @@ -32,10 +34,7 @@ switch_threads: # Save current stack pointer to old thread's stack, if any. movl SWITCH_CUR(%esp), %eax - test %eax, %eax - jz 1f movl %esp, (%eax,%edx,1) -1: # Restore stack pointer from new thread's stack. movl SWITCH_NEXT(%esp), %ecx @@ -47,17 +46,20 @@ switch_threads: popl %ebp popl %ebx ret +.endfunc .globl switch_entry +.func switch_entry switch_entry: # Discard switch_threads() arguments. addl $8, %esp - # Call schedule_tail(prev). + # Call thread_schedule_tail(prev). pushl %eax -.globl schedule_tail - call schedule_tail +.globl thread_schedule_tail + call thread_schedule_tail addl $4, %esp # Start thread proper. ret +.endfunc