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use the new RandomStream class and fix a small bug in the testsuite

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This commit is contained in:
Mathieu Lacage
2007-10-16 13:32:48 +02:00
parent 2922488eb9
commit 87d56eb866
3 changed files with 124 additions and 59 deletions
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168
src/devices/wifi/dcf.cc
View File

@@ -18,31 +18,24 @@
* Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#include <iostream>
#include <cassert>
#include <math.h>
#include "ns3/random-variable.h"
#include "ns3/simulator.h"
#include "ns3/assert.h"
#include "ns3/log.h"
#include "dcf.h"
#include "random-stream.h"
#include "mac-parameters.h"
#define noDCF_TRACE 1
#ifdef DCF_TRACE
# include <iostream>
# define TRACE(x) \
std::cout << "DCF " << x << std::endl;
#else /* DCF_TRACE */
# define TRACE(x)
#endif /* DCF_TRACE */
NS_LOG_COMPONENT_DEFINE ("Dcf");
namespace ns3 {
DcfAccessListener::DcfAccessListener ()
{}
DcfAccessListener::~DcfAccessListener ()
@@ -67,19 +60,19 @@ Dcf::Dcf ()
m_rxing (false)
{
ResetCw ();
m_random = new UniformVariable ();
m_rng = new RealRandomStream ();
}
Dcf::~Dcf ()
{
delete m_random;
delete m_rng;
}
void
Dcf::ResetRng (uint32_t seed)
Dcf::ResetRngForTest (RandomStream *stream)
{
// XXX
// m_random->Reset (seed);
delete m_rng;
m_rng = stream;
}
void
Dcf::SetParameters (MacParameters const*parameters)
@@ -124,24 +117,24 @@ Dcf::RequestAccess (void)
/* don't do anything. We will start a backoff and maybe
* a timer when the txop notifies us of the end-of-access.
*/
TRACE ("accessing. will be notified.");
NS_LOG_DEBUG ("accessing. will be notified.");
}
else if (m_accessTimerEvent.IsRunning ())
{
/* we don't need to do anything because we have an access
* timer which will expire soon.
*/
TRACE ("access timer running. will be notified");
NS_LOG_DEBUG ("access timer running. will be notified");
}
else if (IsBackoffNotCompleted (Now ()) && m_accessTimerEvent.IsExpired ())
{
/* start timer for ongoing backoff.
*/
TRACE ("request access X delayed for="<<delayUntilAccessGranted);
NS_LOG_DEBUG ("request access X delayed for="<<delayUntilAccessGranted);
m_accessTimerEvent = Simulator::Schedule (delayUntilAccessGranted,
&Dcf::AccessTimeout, this);
}
else if (IsPhyBusy ())
else if (IsPhyBusy () || IsNavBusy ())
{
/* someone else has accessed the medium.
* generate a backoff, start timer.
@@ -153,8 +146,8 @@ Dcf::RequestAccess (void)
/* medium is IDLE, we have no backoff running but we
* need to wait a bit before accessing the medium.
*/
TRACE ("request access Y delayed for="<< delayUntilAccessGranted);
assert (m_accessTimerEvent.IsExpired ());
NS_LOG_DEBUG ("request access Y delayed for="<< delayUntilAccessGranted);
NS_ASSERT (m_accessTimerEvent.IsExpired ());
m_accessTimerEvent = Simulator::Schedule (delayUntilAccessGranted,
&Dcf::AccessTimeout, this);
}
@@ -162,7 +155,7 @@ Dcf::RequestAccess (void)
{
/* we can access the medium now.
*/
TRACE ("access granted immediatly");
NS_LOG_DEBUG ("access granted immediatly");
m_listener->AccessGrantedNow ();
}
}
@@ -178,13 +171,13 @@ Dcf::AccessTimeout ()
UpdateBackoff (Now ());
if (m_backoffLeft.IsZero ())
{
TRACE ("timeout access granted");
NS_LOG_DEBUG ("timeout access granted");
m_listener->AccessGrantedNow ();
}
else
{
Time delayUntilAccessGranted = GetDelayUntilAccessGranted (Now ());
TRACE ("timeout access delayed for "<< delayUntilAccessGranted);
NS_LOG_DEBUG ("timeout access delayed for "<< delayUntilAccessGranted);
m_accessTimerEvent = Simulator::Schedule (delayUntilAccessGranted,
&Dcf::AccessTimeout, this);
}
@@ -198,10 +191,8 @@ Dcf::AccessTimeout ()
Time
Dcf::PickBackoffDelay (void)
{
// XXX
//uint32_t pickedCw = m_random->GetSingleValue (0, m_cw);
uint32_t pickedCw = 0;
TRACE ("cw="<<GetCwMin ()<<
uint32_t pickedCw = m_rng->GetNext (0, m_cw);
NS_LOG_DEBUG ("cw="<<GetCwMin ()<<
"<"<<m_cw<<"<"<<GetCwMax ()<<
", picked="<<pickedCw);
Time delay = Scalar (pickedCw) * m_parameters->GetSlotTime ();
@@ -272,7 +263,7 @@ Dcf::GetCwMax (void) const
***************************************************************/
bool
Dcf::IsPhyBusy (void)
Dcf::IsPhyBusy (void) const
{
if (m_rxing)
{
@@ -286,13 +277,24 @@ Dcf::IsPhyBusy (void)
return false;
}
bool
Dcf::IsNavBusy (void) const
{
Time lastNavEnd = m_lastNavStart + m_lastNavDuration;
if (lastNavEnd > Simulator::Now ())
{
return true;
}
return false;
}
void
Dcf::StartBackoff (void)
{
Time backoffStart = Now ();
Time backoffDuration = PickBackoffDelay ();
m_backoffTrace (backoffDuration);
assert (m_backoffStart <= backoffStart);
NS_ASSERT (m_backoffStart <= backoffStart);
m_backoffStart = backoffStart;
m_backoffLeft = backoffDuration;
if (m_listener->AccessNeeded () && m_accessTimerEvent.IsExpired ())
@@ -300,13 +302,13 @@ Dcf::StartBackoff (void)
Time delayUntilAccessGranted = GetDelayUntilAccessGranted (Now ());
if (delayUntilAccessGranted.IsStrictlyPositive ())
{
TRACE ("start at "<<backoffStart<<", for "<<backoffDuration);
NS_LOG_DEBUG ("start at "<<backoffStart<<", for "<<backoffDuration);
m_accessTimerEvent = Simulator::Schedule (delayUntilAccessGranted,
&Dcf::AccessTimeout, this);
}
else
{
TRACE ("access granted now");
NS_LOG_DEBUG ("access granted now");
m_listener->AccessGrantedNow ();
}
}
@@ -314,13 +316,13 @@ Dcf::StartBackoff (void)
{
if (m_accessTimerEvent.IsRunning ())
{
TRACE ("no access needed because timer running.");
NS_LOG_DEBUG ("no access needed because timer running.");
}
if (!m_listener->AccessNeeded ())
{
TRACE ("no access needed.");
NS_LOG_DEBUG ("no access needed.");
}
TRACE ("no access needed for now.");
NS_LOG_DEBUG ("no access needed for now.");
}
}
Time
@@ -353,6 +355,7 @@ Dcf::GetAccessGrantedStart (void) const
busyAccessStart,
txAccessStart,
navAccessStart);
NS_LOG_DEBUG ("access granted start=" << accessGrantedStart);
return accessGrantedStart;
}
@@ -388,8 +391,8 @@ Dcf::UpdateBackoff (Time time)
return;
}
//TRACE ("time: %f, backoffstart: %f\n", time, m_backoffStart);
assert (time >= m_backoffStart);
//NS_LOG_DEBUG ("time: %f, backoffstart: %f\n", time, m_backoffStart);
NS_ASSERT (time >= m_backoffStart);
Time mostRecentEvent = MostRecent (m_backoffStart,
GetAccessGrantedStart ());
@@ -397,9 +400,9 @@ Dcf::UpdateBackoff (Time time)
{
Time newBackoffLeft = m_backoffLeft - (time - mostRecentEvent);
m_backoffLeft = Max (newBackoffLeft, Seconds (0));
TRACE ("at="<<time<<", left="<< m_backoffLeft);
m_backoffStart = time;
}
NS_LOG_DEBUG ("backoff at="<<m_backoffStart<<", left="<< m_backoffLeft);
}
/***************************************************************
@@ -408,11 +411,12 @@ Dcf::UpdateBackoff (Time time)
void
Dcf::NotifyNavReset (Time navStart, Time duration)
{
NS_LOG_DEBUG ("nav reset at="<<navStart<<", for="<<duration);
m_lastNavStart = navStart;
m_lastNavDuration = duration;
Time navEnd = navStart + duration;
Time newDelayUntilAccessGranted = GetDelayUntilAccessGranted (navEnd);
assert (newDelayUntilAccessGranted.IsStrictlyPositive ());
NS_ASSERT (newDelayUntilAccessGranted.IsStrictlyPositive ());
/* This is quite unfortunate but we need to cancel the access timer
* because this nav reset might have brought the time of
* possible access closer to us than expected.
@@ -427,8 +431,8 @@ Dcf::NotifyNavReset (Time navStart, Time duration)
void
Dcf::NotifyNavStart (Time navStart, Time duration)
{
assert (m_lastNavStart < navStart);
TRACE ("nav start at="<<navStart<<", for="<<duration);
NS_ASSERT (m_lastNavStart < navStart);
NS_LOG_DEBUG ("nav start at="<<navStart<<", for="<<duration);
UpdateBackoff (navStart);
m_lastNavStart = navStart;
m_lastNavDuration = duration;
@@ -443,7 +447,7 @@ void
Dcf::NotifyRxStartNow (Time duration)
{
Time now = Now ();
TRACE ("rx start at="<<now<<", for="<<duration);
NS_LOG_DEBUG ("rx start at="<<now<<", for="<<duration);
UpdateBackoff (now);
m_lastRxStart = now;
m_lastRxDuration = duration;
@@ -453,7 +457,7 @@ void
Dcf::NotifyRxEndOkNow (void)
{
Time now = Now ();
TRACE ("rx end ok at="<<now);
NS_LOG_DEBUG ("rx end ok at="<<now);
m_lastRxEnd = now;
m_lastRxReceivedOk = true;
m_rxing = false;
@@ -462,7 +466,7 @@ void
Dcf::NotifyRxEndErrorNow (void)
{
Time now = Now ();
TRACE ("rx end error at=");
NS_LOG_DEBUG ("rx end error at=");
m_lastRxEnd = now;
m_lastRxReceivedOk = false;
m_rxing = false;
@@ -471,7 +475,7 @@ void
Dcf::NotifyTxStartNow (Time duration)
{
Time now = Now ();
TRACE ("tx start at="<<now<<" for "<<duration);
NS_LOG_DEBUG ("tx start at="<<now<<" for "<<duration);
UpdateBackoff (now);
m_lastTxStart = now;
m_lastTxDuration = duration;
@@ -481,7 +485,7 @@ void
Dcf::NotifyCcaBusyStartNow (Time duration)
{
Time now = Now ();
TRACE ("busy start at="<<now<<" for "<<duration);
NS_LOG_DEBUG ("busy start at="<<now<<" for "<<duration);
UpdateBackoff (now);
m_lastBusyStart = now;
m_lastBusyDuration = duration;
@@ -697,7 +701,14 @@ void
DcfTest::StartTest (void)
{
m_dcf = new Dcf ();
m_dcf->ResetRng (0);
TestRandomStream *stream = new TestRandomStream ();
stream->AddNext (1);
stream->AddNext (1);
stream->AddNext (1);
stream->AddNext (1);
stream->AddNext (1);
stream->AddNext (1);
m_dcf->ResetRngForTest (stream);
m_parameters = new MacParameters ();
m_listener = new TestAccessListener (this);
m_dcf->SetParameters (m_parameters);
@@ -729,6 +740,11 @@ DcfTest::RunTests (void)
{
m_failed = false;
// 32 37
// | rx ok |
// | idle | rx ok | nav busy | difs | backoff |
// 0 10 30 40 43 44
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 2+8);
@@ -736,10 +752,15 @@ DcfTest::RunTests (void)
AddAccessRequest (15);
AddAccessRequest (16);
AddAccessRequest (20);
ExpectAccessGranted (51);
ExpectAccessGranted (44);
Simulator::Run ();
EndTest ();
// 32 39
// | rx ok |
// | idle | rx ok | nav busy | | difs | backoff |
// 0 10 30 37 42 43
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 2+5);
@@ -747,7 +768,7 @@ DcfTest::RunTests (void)
AddAccessRequest (15);
AddAccessRequest (16);
AddAccessRequest (20);
ExpectAccessGranted (50);
ExpectAccessGranted (43);
Simulator::Run ();
EndTest ();
@@ -757,6 +778,11 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
// 32 39
// | rx ok |
// | idle | rx ok | nav busy | difs |
// 0 10 30 40 43
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 2+8);
@@ -766,6 +792,11 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
// 32 39
// | rx ok |
// | idle | rx ok | nav busy | difs |
// 0 10 30 40 43
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 2+8);
@@ -775,6 +806,11 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
// 32 39
// | rx ok |
// | idle | rx ok | nav busy | difs |
// 0 10 30 40 43
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 2+8);
@@ -784,6 +820,10 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
//
// | idle | rx error | idle | rx ok | difs |
// 0 10 30 31 38 41
//
StartTest ();
AddRxErrorEvt (10, 20);
AddRxOkEvt (31, 7);
@@ -792,6 +832,10 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
//
// | idle | rx error | idle | rx error | eifs |
// 0 10 30 31 38 42
//
StartTest ();
AddRxErrorEvt (10, 20);
AddRxErrorEvt (31, 7);
@@ -801,16 +845,28 @@ DcfTest::RunTests (void)
EndTest ();
//
// 30 45
// | nav busy |
// | idle | rx ok | idle | rx ok | difs | backoff |
// 0 10 30 35 45 48 49
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 200);
AddRxOkEvt (35, 10);
AddNavReset (45, 45, 0);
AddAccessRequest (32);
ExpectAccessGranted (48);
ExpectAccessGranted (49);
Simulator::Run ();
EndTest ();
//
// 30 45
// | nav busy |
// | idle | rx ok | idle | rx ok |
// 0 10 30 35 45
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 200);
@@ -819,6 +875,12 @@ DcfTest::RunTests (void)
Simulator::Run ();
EndTest ();
//
// 30 45
// | nav busy |
// | idle | rx ok | idle | rx ok | difs |
// 0 10 30 35 45 48
//
StartTest ();
AddRxOkEvt (10, 20);
AddNavStart (30, 30, 200);

12
src/devices/wifi/dcf.h
View File

@@ -29,7 +29,7 @@
namespace ns3 {
class UniformVariable;
class RandomStream;
class MacParameters;
class DcfAccessListener {
@@ -59,8 +59,6 @@ public:
Dcf ();
~Dcf ();
void ResetRng (uint32_t seed);
void SetParameters (const MacParameters *parameters);
void SetDifs (Time difs);
void SetEifs (Time eifs);
@@ -82,6 +80,9 @@ public:
void NotifyNavReset (Time now, Time duration);
void NotifyNavStart (Time now, Time duration);
void NotifyNavContinue (Time now, Time duration);
// for testing only.
void ResetRngForTest (RandomStream *stream);
private:
void AccessTimeout (void);
@@ -96,7 +97,8 @@ private:
uint32_t GetCwMax (void) const;
/* time calculation helpers */
bool IsPhyBusy (void);
bool IsPhyBusy (void) const;
bool IsNavBusy (void) const;
bool IsBackoffNotCompleted (Time now);
Time GetDelayUntilAccessGranted (Time now);
Time GetAccessGrantedStart (void) const;
@@ -104,7 +106,7 @@ private:
EventId m_accessTimerEvent;
UniformVariable *m_random;
RandomStream *m_rng;
const MacParameters *m_parameters;
DcfAccessListener *m_listener;
Time m_difs;

3
src/devices/wifi/wscript
View File

@@ -31,7 +31,8 @@ def build(bld):
'mac-high-nqap.cc',
'mac-high-nqsta.cc',
'wifi-net-device.cc',
'wifi-default-parameters.cc'
'wifi-default-parameters.cc',
'random-stream.cc'
]
headers = bld.create_obj('ns3header')
headers.source = [