gnu-efi/lib/runtime/rtlock.c

   1 /*++
   2
   3 Copyright (c) 1998  Intel Corporation
   4
   5 Module Name:
   6
   7     lock.c
   8
   9 Abstract:
  10
  11     Implements FLOCK
  12
  13
  14
  15 Revision History
  16
  17 --*/
  18
  19
  20 #include "lib.h"
  21
  22
  23
  24 #ifndef __GNUC__
  25 #pragma RUNTIME_CODE(RtAcquireLock)
  26 #endif
  27 VOID
  28 RtAcquireLock (
  29     IN FLOCK    *Lock
  30     )
  31 /*++
  32
  33 Routine Description:
  34
  35     Raising to the task priority level of the mutual exclusion
  36     lock, and then acquires ownership of the lock.
  37
  38 Arguments:
  39
  40     Lock        - The lock to acquire
  41
  42 Returns:
  43
  44     Lock owned
  45
  46 --*/
  47 {
  48     if (BS) {
  49         if (BS->RaiseTPL != NULL) {
  50             Lock->OwnerTpl = uefi_call_wrapper(BS->RaiseTPL, 1, Lock->Tpl);
  51         }
  52     }
  53     else {
  54         if (LibRuntimeRaiseTPL != NULL) {
  55             Lock->OwnerTpl = LibRuntimeRaiseTPL(Lock->Tpl);
  56         }
  57     }
  58     Lock->Lock += 1;
  59     ASSERT (Lock->Lock == 1);
  60 }
  61
  62
  63 #ifndef __GNUC__
  64 #pragma RUNTIME_CODE(RtAcquireLock)
  65 #endif
  66 VOID
  67 RtReleaseLock (
  68     IN FLOCK    *Lock
  69     )
  70 /*++
  71
  72 Routine Description:
  73
  74     Releases ownership of the mutual exclusion lock, and
  75     restores the previous task priority level.
  76
  77 Arguments:
  78
  79     Lock        - The lock to release
  80
  81 Returns:
  82
  83     Lock unowned
  84
  85 --*/
  86 {
  87     EFI_TPL     Tpl;
  88
  89     Tpl = Lock->OwnerTpl;
  90     ASSERT(Lock->Lock == 1);
  91     Lock->Lock -= 1;
  92     if (BS) {
  93         if (BS->RestoreTPL != NULL) {
  94             uefi_call_wrapper(BS->RestoreTPL, 1, Tpl);
  95         }
  96     }
  97     else {
  98         if (LibRuntimeRestoreTPL != NULL) {
  99             LibRuntimeRestoreTPL(Tpl);
 100         }
 101     }
 102 }