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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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#ifndef BRPC_POLICY_CONSTANT_CONCURRENCY_LIMITER_H
#define BRPC_POLICY_CONSTANT_CONCURRENCY_LIMITER_H

#include "brpc/concurrency_limiter.h"

namespace brpc {
namespace policy {

class ConstantConcurrencyLimiter : public ConcurrencyLimiter {
public:
    explicit ConstantConcurrencyLimiter(int max_concurrency);
    
    bool OnRequested(int current_concurrency, Controller*) override;
    
    void OnResponded(int error_code, int64_t latency_us) override;

    int MaxConcurrency() override;

    int ResetMaxConcurrency(const AdaptiveMaxConcurrency&) override;

    ConstantConcurrencyLimiter* New(const AdaptiveMaxConcurrency&) const override;

private:
    butil::atomic<int> _max_concurrency;
};

}  // namespace policy
}  // namespace brpc


#endif // BRPC_POLICY_CONSTANT_CONCURRENCY_LIMITER_H
