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Diffstat (limited to 'src/mscorlib/src/System/Threading/SpinLock.cs')
-rw-r--r--src/mscorlib/src/System/Threading/SpinLock.cs110
1 files changed, 25 insertions, 85 deletions
diff --git a/src/mscorlib/src/System/Threading/SpinLock.cs b/src/mscorlib/src/System/Threading/SpinLock.cs
index dea87435a7..1d90890d6e 100644
--- a/src/mscorlib/src/System/Threading/SpinLock.cs
+++ b/src/mscorlib/src/System/Threading/SpinLock.cs
@@ -12,11 +12,11 @@
//
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
using System;
-using System.Diagnostics;
using System.Security.Permissions;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;
using System.Runtime.ConstrainedExecution;
+using System.Diagnostics;
using System.Diagnostics.Contracts;
namespace System.Threading
@@ -55,7 +55,6 @@ namespace System.Threading
/// </para>
/// </remarks>
[ComVisible(false)]
- [HostProtection(Synchronization = true, ExternalThreading = true)]
[DebuggerTypeProxy(typeof(SystemThreading_SpinLockDebugView))]
[DebuggerDisplay("IsHeld = {IsHeld}")]
public struct SpinLock
@@ -107,7 +106,6 @@ namespace System.Threading
// The waiters count is calculated by m_owner & WAITERS_MASK 01111....110
private static int MAXIMUM_WAITERS = WAITERS_MASK;
-
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.SpinLock"/>
/// structure with the option to track thread IDs to improve debugging.
@@ -123,11 +121,10 @@ namespace System.Threading
if (!enableThreadOwnerTracking)
{
m_owner |= LOCK_ID_DISABLE_MASK;
- Contract.Assert(!IsThreadOwnerTrackingEnabled, "property should be false by now");
+ Debug.Assert(!IsThreadOwnerTrackingEnabled, "property should be false by now");
}
}
-
/// <summary>
/// Initializes a new instance of the <see cref="T:System.Threading.SpinLock"/>
/// structure with the option to track thread IDs to improve debugging.
@@ -157,9 +154,6 @@ namespace System.Threading
/// </exception>
public void Enter(ref bool lockTaken)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
//Try to keep the code and branching in this method as small as possible in order to inline the method
int observedOwner = m_owner;
if (lockTaken || //invalid parameter
@@ -225,7 +219,7 @@ namespace System.Threading
if (totalMilliseconds < -1 || totalMilliseconds > int.MaxValue)
{
throw new System.ArgumentOutOfRangeException(
- "timeout", timeout, Environment.GetResourceString("SpinLock_TryEnter_ArgumentOutOfRange"));
+ nameof(timeout), timeout, Environment.GetResourceString("SpinLock_TryEnter_ArgumentOutOfRange"));
}
// Call reliable enter with the int-based timeout milliseconds
@@ -256,10 +250,6 @@ namespace System.Threading
/// a negative number other than -1, which represents an infinite time-out.</exception>
public void TryEnter(int millisecondsTimeout, ref bool lockTaken)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
-
int observedOwner = m_owner;
if (millisecondsTimeout < -1 || //invalid parameter
lockTaken || //invalid parameter
@@ -277,10 +267,6 @@ namespace System.Threading
/// <param name="lockTaken">The lockTaken param</param>
private void ContinueTryEnter(int millisecondsTimeout, ref bool lockTaken)
{
- //Leave the critical region which is entered by the fast path
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
// The fast path doesn't throw any exception, so we have to validate the parameters here
if (lockTaken)
{
@@ -291,23 +277,15 @@ namespace System.Threading
if (millisecondsTimeout < -1)
{
throw new ArgumentOutOfRangeException(
- "millisecondsTimeout", millisecondsTimeout, Environment.GetResourceString("SpinLock_TryEnter_ArgumentOutOfRange"));
+ nameof(millisecondsTimeout), millisecondsTimeout, Environment.GetResourceString("SpinLock_TryEnter_ArgumentOutOfRange"));
}
-
uint startTime = 0;
if (millisecondsTimeout != Timeout.Infinite && millisecondsTimeout != 0)
{
startTime = TimeoutHelper.GetTime();
}
-#if !FEATURE_CORECLR
- if (CdsSyncEtwBCLProvider.Log.IsEnabled())
- {
- CdsSyncEtwBCLProvider.Log.SpinLock_FastPathFailed(m_owner);
- }
-#endif
-
if (IsThreadOwnerTrackingEnabled)
{
// Slow path for enabled thread tracking mode
@@ -333,18 +311,22 @@ namespace System.Threading
observedOwner = m_owner;
if ((observedOwner & LOCK_ANONYMOUS_OWNED) == LOCK_UNOWNED)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
-
if (Interlocked.CompareExchange(ref m_owner, observedOwner | 1, observedOwner, ref lockTaken) == observedOwner)
{
+ // Aquired lock
return;
}
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
+ if (millisecondsTimeout == 0)
+ {
+ // Did not aquire lock in CompareExchange and timeout is 0 so fail fast
+ return;
+ }
+ }
+ else if (millisecondsTimeout == 0)
+ {
+ // Did not aquire lock as owned and timeout is 0 so fail fast
+ return;
}
else //failed to acquire the lock,then try to update the waiters. If the waiters count reached the maximum, jsut break the loop to avoid overflow
{
@@ -352,17 +334,6 @@ namespace System.Threading
turn = (Interlocked.Add(ref m_owner, 2) & WAITERS_MASK) >> 1 ;
}
-
-
- // Check the timeout.
- if (millisecondsTimeout == 0 ||
- (millisecondsTimeout != Timeout.Infinite &&
- TimeoutHelper.UpdateTimeOut(startTime, millisecondsTimeout) <= 0))
- {
- DecrementWaiters();
- return;
- }
-
//***Step 2. Spinning
//lock acquired failed and waiters updated
int processorCount = PlatformHelper.ProcessorCount;
@@ -377,32 +348,24 @@ namespace System.Threading
observedOwner = m_owner;
if ((observedOwner & LOCK_ANONYMOUS_OWNED) == LOCK_UNOWNED)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
-
int newOwner = (observedOwner & WAITERS_MASK) == 0 ? // Gets the number of waiters, if zero
observedOwner | 1 // don't decrement it. just set the lock bit, it is zzero because a previous call of Exit(false) ehich corrupted the waiters
: (observedOwner - 2) | 1; // otherwise decrement the waiters and set the lock bit
- Contract.Assert((newOwner & WAITERS_MASK) >= 0);
+ Debug.Assert((newOwner & WAITERS_MASK) >= 0);
if (Interlocked.CompareExchange(ref m_owner, newOwner, observedOwner, ref lockTaken) == observedOwner)
{
return;
}
-
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
}
}
- }
- // Check the timeout.
- if (millisecondsTimeout != Timeout.Infinite && TimeoutHelper.UpdateTimeOut(startTime, millisecondsTimeout) <= 0)
- {
- DecrementWaiters();
- return;
+ // Check the timeout.
+ if (millisecondsTimeout != Timeout.Infinite && TimeoutHelper.UpdateTimeOut(startTime, millisecondsTimeout) <= 0)
+ {
+ DecrementWaiters();
+ return;
+ }
}
//*** Step 3, Yielding
@@ -413,22 +376,15 @@ namespace System.Threading
observedOwner = m_owner;
if ((observedOwner & LOCK_ANONYMOUS_OWNED) == LOCK_UNOWNED)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
int newOwner = (observedOwner & WAITERS_MASK) == 0 ? // Gets the number of waiters, if zero
observedOwner | 1 // don't decrement it. just set the lock bit, it is zzero because a previous call of Exit(false) ehich corrupted the waiters
: (observedOwner - 2) | 1; // otherwise decrement the waiters and set the lock bit
- Contract.Assert((newOwner & WAITERS_MASK) >= 0);
+ Debug.Assert((newOwner & WAITERS_MASK) >= 0);
if (Interlocked.CompareExchange(ref m_owner, newOwner, observedOwner, ref lockTaken) == observedOwner)
{
return;
}
-
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
}
if (yieldsoFar % SLEEP_ONE_FREQUENCY == 0)
@@ -470,7 +426,7 @@ namespace System.Threading
if ((observedOwner & WAITERS_MASK) == 0) return; // don't decrement the waiters if it's corrupted by previous call of Exit(false)
if (Interlocked.CompareExchange(ref m_owner, observedOwner - 2, observedOwner) == observedOwner)
{
- Contract.Assert(!IsThreadOwnerTrackingEnabled); // Make sure the waiters never be negative which will cause the thread tracking bit to be flipped
+ Debug.Assert(!IsThreadOwnerTrackingEnabled); // Make sure the waiters never be negative which will cause the thread tracking bit to be flipped
break;
}
spinner.SpinOnce();
@@ -483,7 +439,7 @@ namespace System.Threading
/// </summary>
private void ContinueTryEnterWithThreadTracking(int millisecondsTimeout, uint startTime, ref bool lockTaken)
{
- Contract.Assert(IsThreadOwnerTrackingEnabled);
+ Debug.Assert(IsThreadOwnerTrackingEnabled);
int lockUnowned = 0;
// We are using thread IDs to mark ownership. Snap the thread ID and check for recursion.
@@ -510,17 +466,10 @@ namespace System.Threading
if (m_owner == lockUnowned)
{
-#if !FEATURE_CORECLR
- Thread.BeginCriticalRegion();
-#endif
if (Interlocked.CompareExchange(ref m_owner, m_newOwner, lockUnowned, ref lockTaken) == lockUnowned)
{
return;
}
-#if !FEATURE_CORECLR
- // The thread failed to get the lock, so we don't need to remain in a critical region.
- Thread.EndCriticalRegion();
-#endif
}
// Check the timeout. We only RDTSC if the next spin will yield, to amortize the cost.
if (millisecondsTimeout == 0 ||
@@ -550,11 +499,6 @@ namespace System.Threading
ExitSlowPath(true);
else
Interlocked.Decrement(ref m_owner);
-
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
-
}
/// <summary>
@@ -586,10 +530,6 @@ namespace System.Threading
}
else
ExitSlowPath(useMemoryBarrier);
-
-#if !FEATURE_CORECLR
- Thread.EndCriticalRegion();
-#endif
}
/// <summary>
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-16 16:50:22 +0000