66 lines
1.8 KiB
C#
66 lines
1.8 KiB
C#
namespace PerfectNumbers.Core.Gpu;
|
|
|
|
public static class GpuWorkLimiter
|
|
{
|
|
private static SemaphoreSlim _semaphore = new(1, int.MaxValue);
|
|
private static readonly object _lock = new();
|
|
private static int _currentLimit = 1;
|
|
|
|
public static IDisposable Acquire()
|
|
{
|
|
// TODO: Replace the per-call Releaser allocation with the pooled struct-based guard from the
|
|
// GpuLimiterThroughputBenchmarks so limiter acquisition does not allocate when we enter the
|
|
// GPU scanning hot path.
|
|
var sem = _semaphore;
|
|
sem.Wait();
|
|
return new Releaser(sem);
|
|
}
|
|
|
|
public static void SetLimit(int value)
|
|
{
|
|
if (value < 1)
|
|
{
|
|
value = 1;
|
|
}
|
|
|
|
lock (_lock)
|
|
{
|
|
if (value == _currentLimit)
|
|
{
|
|
return;
|
|
}
|
|
|
|
// Swap to a new semaphore for the new limit. We intentionally
|
|
// do not dispose the old semaphore to avoid releasing handles
|
|
// that may still be in use by existing Releaser instances.
|
|
// TODO: Consolidate with GpuPrimeWorkLimiter so both limiters share a pooled SemaphoreSlim and avoid rebuilding the
|
|
// limiter state whenever limits are adjusted from the CLI.
|
|
_semaphore = new SemaphoreSlim(value, value);
|
|
_currentLimit = value;
|
|
}
|
|
}
|
|
|
|
private sealed class Releaser : IDisposable
|
|
{
|
|
private readonly SemaphoreSlim _sem;
|
|
private bool _disposed;
|
|
|
|
public Releaser(SemaphoreSlim sem)
|
|
{
|
|
_sem = sem;
|
|
}
|
|
|
|
public void Dispose()
|
|
{
|
|
if (_disposed)
|
|
{
|
|
return;
|
|
}
|
|
|
|
_sem.Release();
|
|
_disposed = true;
|
|
}
|
|
}
|
|
}
|
|
|