policy_pf.hh revision 13023 
13760SN/A/*
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53760SN/A * The license below extends only to copyright in the software and shall
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243760SN/A *
253760SN/A * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
263760SN/A * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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293760SN/A * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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3111793Sbrandon.potter@amd.com * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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353760SN/A * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
365597Sgblack@eecs.umich.edu *
373760SN/A * Author: Giacomo Travaglini
38 */
39
40#ifndef __MEM_QOS_POLICY_PF_HH__
41#define __MEM_QOS_POLICY_PF_HH__
42
43#include "mem/qos/policy.hh"
44#include "params/QoSPropFairPolicy.hh"
45
46namespace QoS {
47
48/**
49 * Proportional Fair QoS Policy
50 * Providing a configurable fair scheduling policy based on
51 * utilization; utilization is directly proportional to a
52 * score which is inversely proportional to the QoS priority
53 * Users can tune the policy by adjusting the weight parameter
54 * (weight of the formula)
55 *
56 * This is the formula used by the policy
57 * ((1.0 - weight) * old_score) + (weight * served_bytes);
58 */
59class PropFairPolicy : public Policy
60{
61    using Params = QoSPropFairPolicyParams;
62    const Params *params() const
63    { return static_cast<const Params *>(_params); }
64
65  public:
66    PropFairPolicy(const Params*);
67    virtual ~PropFairPolicy();
68
69    /**
70     * Initialize the master's score by providing
71     * the master's name and initial score value.
72     * The master's name has to match a name in the system.
73     *
74     * @param master master's name to lookup.
75     * @param score initial score value for the master
76     */
77    void initMasterName(const std::string master, const double score);
78
79    /**
80     * Initialize the master's score by providing
81     * the master's SimObject pointer and initial score value.
82     * The master's pointer has to match a master in the system.
83     *
84     * @param master master's SimObject pointer to lookup.
85     * @param score initial score value for the master
86     */
87    void initMasterObj(const SimObject* master, const double score);
88
89    /**
90     * Schedules a packet based on proportional fair configuration
91     *
92     * @param m_id master id to schedule
93     * @param pkt_size size of the packet
94     * @return QoS priority value
95     */
96    virtual uint8_t
97    schedule(const MasterID m_id, const uint64_t pkt_size) override;
98
99  protected:
100    template <typename Master>
101    void initMaster(const Master master, const double score);
102
103    inline double
104    updateScore(const double old_score, const uint64_t served_bytes) const;
105
106  protected:
107    /** PF Policy weight */
108    const double weight;
109
110    /** history is keeping track of every master's score */
111    using MasterHistory = std::pair<MasterID, double>;
112    std::vector<MasterHistory> history;
113};
114
115} // namespace QoS
116
117#endif // __MEM_QOS_POLICY_PF_HH__
118