src/user/leakybucket.c

   1 #include "leakybucket.h"
   2 #include <math.h> // for ceil
   3
   4
   5 /////////////////////////////////////////////////////////////////////////////
   6 // Dual Leaky Bucket
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 // Issue: we need to change the code to be according to the ATMF GCRA
  10 // and to be with integer logic!
  11
  12 // Issue: what is implemented now is a dual token bucket similar to the
  13 // "Two-Rate Three Color Marker" defined in RFC2698
  14 // the counter, however, counts up for each packet (in RFC2698 it counts down)
  15
  16
  17 LeakyBucket::LeakyBucket(void)
  18 {
  19    value = 0;
  20    max = 0;
  21    last_update = 0;
  22 } // LeakyBucket::LeakyBucket(void) - constructor
  23
  24 LeakyBucket::~LeakyBucket(void)
  25 {
  26 }
  27
  28 void LeakyBucket::SetParam(double rate, int burstsize)
  29 {
  30    decrement_per_slot = rate / 8.0 * SlotLength;
  31    max = burstsize;
  32
  33    //printf("LeakyBucket::SetParam : decrement_per_slot=%f max=%f\n",
  34    //    decrement_per_slot, max);
  35
  36 } // LeakyBucket::SetParam(double rate, int burstsize)
  37
  38 /////////////////////////////////////////////////////////
  39 // LeakyBucket::PacketArrivalConformance
  40 // A packet of with framelength "bytes" has arrived, is
  41 // this packet conforming?
  42 // The buckets are increased
  43 // Return value:
  44 //  0 - packet is not conforming
  45 //  1 - packet is conforming
  46 /////////////////////////////////////////////////////////
  47 int LeakyBucket::PacketArrivalConformance(int bytes)
  48 {
  49    update();
  50
  51    value += bytes;
  52
  53    //printf("value=%f\n",value);
  54
  55    if(value > max)
  56    {
  57       value -= bytes;
  58       return 0;   // not conforming
  59    }
  60    else
  61       return 1;   // conforming
  62
  63 }; // LeakyBucket::PacketArrivalConformance(int bytes)
  64
  65 /////////////////////////////////////////////////////////
  66 // LeakyBucket::Update
  67 // Update the LeakyBucket counter to the current time
  68 // we decrement the counter by n*decrement_per_slot
  69 // decrement_per_slot determines the data rate
  70 /////////////////////////////////////////////////////////
  71 void LeakyBucket::update(void)
  72 {
  73    int n;
  74    n = SimTime - last_update;
  75    if(n >= 0)
  76         {
  77         value -= (double) (n * decrement_per_slot);
  78         if(value < 0)
  79         value = 0;
  80         } // decrement only
  81
  82    last_update = SimTime;
  83
  84 } // LeakyBucket::update(void)
  85
  86
  87 /////////////////////////////////////////////////////////////////////////////
  88 // Dual Leaky Bucket
  89 /////////////////////////////////////////////////////////////////////////////
  90 DualLeakyBucket::DualLeakyBucket(root* owner)
  91 {
  92   pOwner = owner;
  93   pLbCir = NULL;
  94   pLbPir = NULL;
  95   CHECK(pLbCir = new LeakyBucket());
  96   CHECK(pLbPir = new LeakyBucket());
  97 }
  98
  99 DualLeakyBucket::~DualLeakyBucket(void)
 100 {
 101   if (pLbCir)
 102     delete pLbCir;
 103   if (pLbPir)
 104     delete pLbPir;
 105 }
 106
 107 /////////////////////////////////////////////////////////
 108 // DualLeakyBucket::SetParam
 109 // Set the parameters for a dual leaky bucket
 110 /////////////////////////////////////////////////////////
 111 void DualLeakyBucket::SetParam(double cir, int cbs, double pir, int pbs)
 112 {
 113    pLbCir->SetParam(cir, cbs);
 114    pLbPir->SetParam(pir, pbs);
 115 }
 116
 117 /////////////////////////////////////////////////////////
 118 // DualLeakyBucket::PacketArrivalConformance(bytes)
 119 // A packet of with framelength "bytes" has arrived, is
 120 // this packet conforming?
 121 // The buckets are increased
 122 // Return value:
 123 //      TRUE if packet is conforming and need not be dropped
 124 //      FALSE if packet is not conforming and must be dropped
 125 //      *PDropPrec = 0 (green), 1 (yellow) or 2 (red)
 126 /////////////////////////////////////////////////////////
 127 int DualLeakyBucket::PacketArrivalConformance(int bytes,int *pDropPrec)
 128 {
 129
 130 // issue: we need to add the color-aware mode
 131 // issue: in the data processing spec I have defined separate handling
 132 //   for PIR and CIR, here it is combined
 133
 134    int confCir, confPir;
 135
 136    confCir = pLbCir->PacketArrivalConformance(bytes);
 137    confPir = pLbPir->PacketArrivalConformance(bytes);
 138
 139         if(action == 0)
 140            return TRUE;                 //packet always conforming
 141         else if(action == 1)    // mark - impelement 2-Rate 3color marker (RFC2698)
 142         {
 143            if(!confPir)                 // PIR bucket not conforming
 144                    *pDropPrec = 2;      // red
 145                 else if(!confCir)               // CIR bucket not conforming
 146                    *pDropPrec = 1;      // yellow
 147                 else
 148                    *pDropPrec = 0;      // green
 149
 150                 return TRUE;                    // packet is conforming and not dropped
 151         }
 152         else if (action == 2)   // drop if CIR bucket not conforming
 153         {
 154                 if(!confCir)                    // not conforming to CIR
 155          return FALSE;
 156         }
 157         else if (action == 3)   // drop if PIR bucket not conforming
 158         {
 159                 if(!confPir)                    // PIR bucket not conforming
 160          return FALSE;          // drop packet
 161         }
 162         else
 163         {
 164            errm2s2d("%s: (file %s, line %d) Internal error: policing action %d shall be applied but no rule exists",
 165            pOwner->name, __FILE__, __LINE__, action);
 166         }
 167
 168         return TRUE;
 169
 170 } // DualLeakyBucket::PacketArrivalConformance(int bytes,int *pDropPrec)
 171