Add Weighted RED Qos

Bug 4296
Ehancement to allow configuring GRED as form of weighted RED.

1 files changed, 177 insertions, 0 deletions

diff --git a/lib/Vyatta/Qos/WeightedRandom.pm b/lib/Vyatta/Qos/WeightedRandom.pm
new file mode 100644
index 0000000..12e591a
--- /dev/null
+++ b/lib/Vyatta/Qos/WeightedRandom.pm
@@ -0,0 +1,177 @@
+# Weighted Random i.e. GRED (Generic Random Early Detect)
+#
+# **** License ****
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+# This code was originally developed by Vyatta, Inc.
+# Portions created by Vyatta are Copyright (C) 2008 Vyatta, Inc.
+# All Rights Reserved.
+# **** End License ****
+
+package Vyatta::Qos::WeightedRandom;
+use strict;
+use warnings;
+
+require Vyatta::Config;
+require Vyatta::Qos::ShaperClass;
+
+my $wred = 'weighted-random-detect';
+
+# Create a new instance based on config information
+sub new {
+    my ( $that, $config, $name ) = @_;
+    my $level = $config->setLevel();
+    my $rate  = $config->returnValue("bandwidth");
+
+    my @classes = _getClasses($level);
+
+    _checkClasses( $level, $rate, @classes );
+
+    my $self = {};
+    my $class = ref($that) || $that;
+    bless $self, $class;
+    $self->{_classes} = \@classes;
+
+    return $self;
+}
+
+sub _getClasses {
+    my $level = shift;
+    my @classes;
+    my $config = new Vyatta::Config;
+
+    $config->setLevel($level);
+    $config->exists("default")
+      or die "$level configuration not complete: missing default class\n";
+
+    $config->setLevel("$level default");
+    push @classes, new Vyatta::Qos::ShaperClass($config);
+    $config->setLevel($level);
+
+    foreach my $id ( $config->listNodes("class") ) {
+        $config->setLevel("$level class $id");
+        push @classes, new Vyatta::Qos::ShaperClass( $config, $id );
+    }
+
+    return @classes;
+}
+
+# Check constraints on class bandwidth values
+sub _checkClasses {
+    my $level   = shift;
+    my $rate    = shift;
+    my $default = shift;
+
+    # if auto, can't check at create must wait for policy to be applied
+    $rate = ( $rate eq "auto" ) ? undef : getRate($rate);
+    $default->rateCheck( $rate, "$level default" ) if $rate;
+
+    foreach my $class (@_) {
+        die "$class->{level} bandwidth not defined\n" unless $class->{_rate};
+        $class->rateCheck( $rate, "$level class $class->{id}" ) if $rate;
+    }
+}
+
+sub commands {
+    my ( $self, $dev ) = @_;
+    my $rate    = getAutoRate( $self->{_rate}, $dev );
+    my $classes = $self->{_classes};
+    my $default = shift @$classes;
+    my $maxid   = 1;
+
+    $default->rateCheck( $rate, "$self->{_level} default" );
+    foreach my $class (@$classes) {
+        $class->rateCheck( $rate, "$self->{_level} class $class->{id}" );
+
+        # find largest class id
+        if ( defined $class->{id} && $class->{id} > $maxid ) {
+            $maxid = $class->{id};
+        }
+    }
+
+    # fill in id of default
+    $default->{id} = ++$maxid;
+    unshift @$classes, $default;
+
+    print "qdisc add dev $dev root handle 1: gred";
+    print " setup DPs $maxid default $maxid";
+
+    foreach my $class (@$classes) {
+        my $classbw = $class->get_rate($rate);
+        my $avg     = $class->{_avgpkt};
+        my $latency = $class->{_latency};
+
+        my ( $qmin, $qmax, $burst ) = RedParam( $classbw, $latency, $avg );
+
+        print "qdisc chang dev $dev root gred ";
+        printf "limit %d min %d max %d avpkt %d", 4 * $qmax, $qmin, $qmax, $avg;
+        printf " burst %d probability 0.02 bandwidth %d ecn\n",
+          $burst, $classbw / 1000;
+
+        foreach my $match ( $class->matchRules() ) {
+            $match->filter( $dev, 1, $class->{_priority} );
+            printf " flowid :%x\n", $class->{id};
+        }
+    }
+}
+
+# Walk configuration tree and look for changed nodes
+# The configuration system should do this but doesn't do it right
+sub isChanged {
+    my ( $self, $name ) = @_;
+    my $config = new Vyatta::Config;
+    my @attributes =
+      qw(bandwidth burst latency packet-length priority queue-limit);
+
+    $config->setLevel("qos-policy $wred $name");
+
+    return 'bandwidth' if ( $config->isChanged('bandwidth') );
+
+    foreach my $attr (@attributes) {
+	return "default $attr" if ( $config->isChanged("default $attr") );
+    }
+
+    my %classNodes = $config->listNodeStatus('class');
+    while ( my ( $class, $status ) = each %classNodes ) {
+        return "class $class" if ( $status ne 'static' );
+
+        foreach my $attr (@attributes) {
+            return "class $class $attr"
+              if ( $config->isChanged("class $class $attr") );
+        }
+
+        my %matchNodes = $config->listNodeStatus("class $class match");
+        while ( my ( $match, $status ) = each %matchNodes ) {
+            my $level = "class $class match $match";
+            return $level if ( $status ne 'static' );
+
+            foreach my $parm (
+                'vif',
+                'ether destination',
+                'ether source',
+                'ether protocol',
+                'interface',
+                'ip dscp',
+                'ip protocol',
+                'ip source address',
+                'ip destination address',
+                'ip source port',
+                'ip destination port'
+              )
+            {
+                return "$level $parm" if ( $config->isChanged("$level $parm") );
+            }
+        }
+    }
+
+    return;    # false
+}
+
+1;