diff options
Diffstat (limited to 'MdePkg/Library/BaseLib/SynchronizationGcc.c')
| -rw-r--r-- | MdePkg/Library/BaseLib/SynchronizationGcc.c | 63 |
1 files changed, 47 insertions, 16 deletions
diff --git a/MdePkg/Library/BaseLib/SynchronizationGcc.c b/MdePkg/Library/BaseLib/SynchronizationGcc.c index 1681b4cf44..4c30dbc4b1 100644 --- a/MdePkg/Library/BaseLib/SynchronizationGcc.c +++ b/MdePkg/Library/BaseLib/SynchronizationGcc.c @@ -110,15 +110,32 @@ AcquireSpinLock ( IN OUT SPIN_LOCK *SpinLock
)
{
- UINT64 Tick;
- UINT64 Start, End;
- UINT64 Timeout;
+ UINT64 Current;
+ UINT64 Previous;
+ UINT64 Total;
+ UINT64 Start;
+ UINT64 End;
+ UINT64 Timeout;
+ INT64 Cycle;
+ INT64 Delta;
- Tick = 0;
- Start = 0;
- End = 0;
if (PcdGet32 (PcdSpinLockTimeout) > 0) {
- Tick = GetPerformanceCounter ();
+ //
+ // Get the current timer value
+ //
+ Current = GetPerformanceCounter();
+
+ //
+ // Initialize local variables
+ //
+ Start = 0;
+ End = 0;
+ Total = 0;
+
+ //
+ // Retrieve the performance counter properties and compute the number of performance
+ // counter ticks required to reach the timeout
+ //
Timeout = DivU64x32 (
MultU64x32 (
GetPerformanceCounterProperties (&Start, &End),
@@ -126,16 +143,30 @@ AcquireSpinLock ( ),
1000000
);
- if (Start < End) {
- Tick += Timeout;
- } else {
- Tick -= Timeout;
+ Cycle = End - Start;
+ if (Cycle < 0) {
+ Cycle = -Cycle;
+ }
+ Cycle++;
+
+ while (!AcquireSpinLockOrFail (SpinLock)) {
+ CpuPause ();
+ Previous = Current;
+ Current = GetPerformanceCounter();
+ Delta = (INT64) (Current - Previous);
+ if (Start > End) {
+ Delta = -Delta;
+ }
+ if (Delta < 0) {
+ Delta += Cycle;
+ }
+ Total += Delta;
+ ASSERT (Total < Timeout);
+ }
+ } else {
+ while (!AcquireSpinLockOrFail (SpinLock)) {
+ CpuPause ();
}
- }
-
- while (!AcquireSpinLockOrFail (SpinLock)) {
- CpuPause ();
- ASSERT ((Start < End) ^ (Tick <= GetPerformanceCounter ()));
}
return SpinLock;
}
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