arch/x86/lib/thunk_64.S

   1 /*
   2  * Save registers before calling assembly functions. This avoids
   3  * disturbance of register allocation in some inline assembly constructs.
   4  * Copyright 2001,2002 by Andi Kleen, SuSE Labs.
   5  * Subject to the GNU public license, v.2. No warranty of any kind.
   6  */
   7
   8         #include <linux/linkage.h>
   9         #include <asm/dwarf2.h>
  10         #include <asm/calling.h>
  11         #include <asm/rwlock.h>
  12
  13         /* rdi: arg1 ... normal C conventions. rax is saved/restored. */
  14         .macro thunk name,func
  15         .globl \name
  16 \name:
  17         CFI_STARTPROC
  18         SAVE_ARGS
  19         call \func
  20         jmp  restore
  21         CFI_ENDPROC
  22         .endm
  23
  24         /* rdi: arg1 ... normal C conventions. rax is passed from C. */
  25         .macro thunk_retrax name,func
  26         .globl \name
  27 \name:
  28         CFI_STARTPROC
  29         SAVE_ARGS
  30         call \func
  31         jmp  restore_norax
  32         CFI_ENDPROC
  33         .endm
  34
  35
  36         .section .sched.text, "ax"
  37 #ifdef CONFIG_RWSEM_XCHGADD_ALGORITHM
  38         thunk rwsem_down_read_failed_thunk,rwsem_down_read_failed
  39         thunk rwsem_down_write_failed_thunk,rwsem_down_write_failed
  40         thunk rwsem_wake_thunk,rwsem_wake
  41         thunk rwsem_downgrade_thunk,rwsem_downgrade_wake
  42 #endif
  43
  44 #ifdef CONFIG_TRACE_IRQFLAGS
  45         thunk trace_hardirqs_on_thunk,trace_hardirqs_on
  46         thunk trace_hardirqs_off_thunk,trace_hardirqs_off
  47 #endif
  48
  49 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  50         thunk lockdep_sys_exit_thunk,lockdep_sys_exit
  51 #endif
  52
  53         /* SAVE_ARGS below is used only for the .cfi directives it contains. */
  54         CFI_STARTPROC
  55         SAVE_ARGS
  56 restore:
  57         RESTORE_ARGS
  58         ret
  59         CFI_ENDPROC
  60
  61         CFI_STARTPROC
  62         SAVE_ARGS
  63 restore_norax:
  64         RESTORE_ARGS 1
  65         ret
  66         CFI_ENDPROC