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-rwxr-xr-xscripts/system/irq-affinity.pl382
1 files changed, 0 insertions, 382 deletions
diff --git a/scripts/system/irq-affinity.pl b/scripts/system/irq-affinity.pl
deleted file mode 100755
index de0c3099..00000000
--- a/scripts/system/irq-affinity.pl
+++ /dev/null
@@ -1,382 +0,0 @@
-#!/usr/bin/perl
-
-# **** 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) 2009,2010 Vyatta, Inc.
-# All Rights Reserved.
-#
-# **** End License ****
-#
-use warnings;
-use strict;
-use Sys::Syslog qw(:standard :macros);
-
-my $PATH_SYS_SYSTEM = "/sys/devices/system";
-my $PATH_SYS_CPU0 = $PATH_SYS_SYSTEM . "/cpu/cpu0";
-
-die "Usage: $0 ifname {auto | mask} { debug }\n" if ($#ARGV < 1);
-
-my ($ifname, $mask, $debug) = @ARGV;
-
-die "Error: Interface $ifname does not exist\n"
- unless -d "/sys/class/net/$ifname";
-
-my $logopt = defined($debug) ? "perror" : "";
-openlog("irq-affinity", $logopt, LOG_LOCAL0);
-
-my ($cpus, undef, $threads) = cpuinfo();
-
-if ($mask eq 'auto') {
- affinity_auto($ifname);
-} else {
- affinity_mask($ifname, $mask);
-}
-
-exit 0;
-
-# Get current irq assignments by reading /proc/interrupts
-# returns reference to hash of interrupt infromation for given interface
-# i.e. {'eth1'} => 22, {'eth1-tx-1'} => 31, ...
-#
-# Code based on parsing in irqbalance program
-#
-# Format of /proc/interrupts is:
-#
-# CPU0 CPU1
-# 72: 1637 0 PCI-MSI-edge eth3
-sub irqinfo {
- my $ifname = shift;
- my $irqmap;
-
- open( my $f, '<', "/proc/interrupts" )
- or die "Can't read /proc/interrupts";
-
- # first line is the header we don't need
- <$f>;
-
- while (<$f>) {
- chomp;
-
- # lines with letters in front are special, like NMI count.
- #
- # First column is IRQ number (and colon)
- # after that match as many entries with digits
- last unless /^\s*(\d+):\s/;
- my $irq = $1;
-
- my @cols = split;
-
- # skip the irq number and all counts
- do {
- shift @cols;
- } while ($cols[0] =~ /^\d+$/);
-
- foreach my $name ( @cols ) {
- $name =~ s/,$//;
-
- next unless ($name eq $ifname || $name =~ /^$ifname-/ );
-
- $irqmap->{$name} = $irq;
- }
- }
- close $f;
-
- return $irqmap;
-}
-
-# compute number of bits set
-sub hweight {
- my $bits = shift;
- my $count = 0;
-
- for (; $bits > 0; $bits >>= 1) {
- ++$count if ($bits & 1);
- }
- return $count;
-}
-
-# count the bits set in a mapping file
-sub path_sibling {
- my $path = shift;
- my $result = 0;
-
- open (my $f, '<', $path)
- or die "can't open $path : $!";
-
- my $line = <$f>;
- close $f;
- chomp $line;
-
- for my $mask (split(/,/, $line)) {
- $result += hweight(hex($mask));
- }
-
- return $result;
-}
-
-# Determine number of cpu topology information
-#
-# This algorithm is based on the command lscpu from util-linux
-# it cases like multiple socket, offline cpus, etc
-sub cpuinfo {
- my $cpu = 0;
-
- # XXX doesn't handle offline CPU's...
- while ( -e $PATH_SYS_SYSTEM . '/cpu/cpu' . $cpu ) {
- ++$cpu;
- }
-
- my $thread = path_sibling($PATH_SYS_CPU0 . '/topology/thread_siblings');
- my $core = path_sibling($PATH_SYS_CPU0 . '/topology/core_siblings') / $thread;
- my $socket = $cpu / $core / $thread;
-
- syslog(LOG_DEBUG, "cpus=%d cores=%d threads=%d sockets=%d\n",
- $cpu, $core, $thread, $socket);
-
- return ($cpu, $core, $thread);
-}
-
-# Set affinity value for a irq
-sub set_affinity {
- my ( $ifname, $irq, $mask ) = @_;
- my $smp_affinity = "/proc/irq/$irq/smp_affinity";
-
- syslog(LOG_DEBUG, "%s: irq %d affinity set to 0x%x", $ifname, $irq, $mask);
-
- open( my $f, '>', $smp_affinity )
- or die "Can't open: $smp_affinity : $!\n";
- printf {$f} "%x\n", $mask;
- close $f;
-}
-
-# set Receive Packet Steering mask
-sub set_rps {
- my ( $ifname, $q, $mask ) = @_;
-
- # ignore if older kernel without RPS
- my $rxq = "/sys/class/net/$ifname/queues";
- return unless ( -d $rxq );
-
- syslog(LOG_INFO, "%s: receive queue %d cpus set to 0x%x",
- $ifname, $q, $mask);
-
- my $rps_cpus = "$rxq/rx-$q/rps_cpus";
- open( my $f, '>', $rps_cpus )
- or die "Can't open: $rps_cpus : $!\n";
- printf {$f} "%x\n", $mask;
- close $f;
-}
-
-# Check if the current if this cpu is in the banned mask
-# Uses environment variable VYATTA_IRQAFFINITY_BANNED_CPUS
-# to mask cpus which irq affinity script should ignore
-sub skip_cpu {
- my $cpu = shift;
- my $banned = $ENV{'VYATTA_IRQAFFINITY_BANNED_CPUS'};
-
- return unless defined($banned); # false
-
- return ((1 << $cpu) & hex($banned)) != 0;
-}
-
-# For multi-queue NIC choose next cpu to be on next core
-# XXX doesn't handle offline CPU's...
-sub next_cpu {
- my $origcpu = shift;
- my $cpu = $origcpu;
-
- do {
- $cpu += $threads;
- if ( $cpu >= $cpus ) {
- # wraparound to next thread on core 0
- $cpu = ($cpu + 1) % $threads;
- }
- } while ($cpu != $origcpu && skip_cpu($cpu));
-
- return $cpu;
-}
-
-# Get cpu to assign for the queues for single queue nic
-sub choose_cpu {
- my $ifname = shift;
-
- # For single-queue nic choose IRQ based on name
- # Ideally should make decision on least loaded CPU
- my ($ifunit) = ($ifname =~ m/^[a-z]*(\d+)$/);
- die "can't find number for $ifname\n"
- unless defined($ifunit);
-
- # Give the load first to one CPU of each hyperthreaded core, then
- # if there are enough NICs, give the load to the other CPU of
- # each core.
- # XXX doesn't handle offline CPU's...
- my $ht_wrap = (($ifunit * $threads) / $cpus) % $threads;
- my $cpu = ((($ifunit * $threads) + $ht_wrap) % $cpus);
-
- $cpu = next_cpu($cpu) if skip_cpu($cpu);
- return $cpu;
-}
-
-# Assignment for multi-queue NICs
-sub assign_multiqueue {
- my $ifname = shift;
- my $irqmap = shift;
- my $numq = scalar(@_);
- my $cpu;
-
- if ($numq == 1) {
- # This is a single-queue NIC using the multi-queue naming
- # format. In this case, we use the same algorithm to select
- # the CPU as we use for standard single-queue NICs. This
- # algorithm spreads the work of different NICs accross
- # different CPUs.
-
- $cpu = choose_cpu($ifname);
- } else {
- # For multi-queue nic's always starts with CPU 0
- # This is less than ideal when there are more core's available
- # than number of queues (probably should barber pole);
- # but the Intel IXGBE needs CPU 0 <-> queue 0
- # because of flow director bug.
-
- $cpu = 0;
- }
-
- foreach my $name (sort @_) {
- my $irq = $irqmap->{$name};
-
- die "Can't find irq in map for $name\n" unless $irq;
-
- syslog(LOG_INFO, "%s: assign %s to cpu %d",
- $ifname, $name, $cpu );
-
- # Assign CPU affinity for both IRQs
- set_affinity( $ifname, $irq, 1 << $cpu );
-
- # TODO use RPS to steer data if cores > queues?
- $cpu = next_cpu($cpu);
- }
-}
-
-# Affinity assignment function for single-queue NICs. The strategy
-# here is to just spread the interrupts of different NICs evenly
-# across all CPUs. That is the best we can do without monitoring the
-# load and traffic patterns. So we just directly map the NIC unit
-# number into a CPU number.
-sub assign_single {
- my ( $ifname, $irq ) = @_;
- my $cpu = choose_cpu($ifname);
-
- syslog(LOG_INFO,"%s: assign irq %d to cpu %d", $ifname, $irq, $cpu );
-
- set_affinity( $ifname, $irq, 1 << $cpu );
-
- if ($threads > 1) {
- # Use both threads on this cpu if hyperthreading
- my $mask = ((1 << $threads) - 1) << $cpu;
- set_rps($ifname, 0, $mask);
- }
- # MAYBE - Use all cpu's if no HT
-}
-
-# Mask must contain at least one CPU and
-# no bits outside of range of available CPU's
-sub check_mask {
- my ($ifname, $name, $mask) = @_;
- my $m = hex($mask);
-
- die "$ifname: $name mask $mask has no bits set\n"
- if ($m == 0);
-
- die "$ifname: $name mask $mask too large for number of CPU's: $cpus\n"
- if ($m >= 1 << $cpus);
-}
-
-# Set affinity (and RPS) based on mask
-sub affinity_mask {
- my ($ifname, $mask) = @_;
-
- # match on <hex> or <hex>,<hex>
- unless ($mask =~ /^([0-9a-f]+)(|,([0-9a-f]+))$/) {
- die "$ifname: irq mask $mask is not a valid affinity mask\n"
- }
-
- my $irqmsk = $1;
- my $rpsmsk = $3;
-
- check_mask($ifname, "irq", $irqmsk);
- check_mask($ifname, "rps", $rpsmsk) if $rpsmsk;
-
- my $irqmap = irqinfo($ifname);
- while (my ($name, $irq) = each (%{$irqmap})) {
- syslog(LOG_INFO, "%s: assign irq %d mask %s", $name, $irq, $irqmsk);
- set_affinity($name, $irq, hex($irqmsk));
- }
-
- set_rps($ifname, 0, hex($rpsmsk)) if $rpsmsk;
-}
-
-# The auto strategy involves trying to achieve the following goals:
-#
-# - Spread the receive load among as many CPUs as possible.
-#
-# - For all multi-queue NICs in the system that provide both tx and
-# rx queues, keep all of the queues that share the same queue
-# number on same CPUs. I.e. tx and rx queue 0 of all such NICs
-# should interrupt one CPU; tx and rx queue 1 should interrupt a
-# different CPU, etc.
-#
-# - If hyperthreading is supported and enabled, avoid assigning
-# queues to both CPUs of a hyperthreaded pair if there are enough
-# CPUs available to do that.
-sub affinity_auto {
- my $ifname = shift;
-
- my $irqmap = irqinfo($ifname);
- my @irqnames = keys %{$irqmap};
- my $numirq = scalar(@irqnames);
-
- # Figure out what style of irq naming is being used
- if ( $numirq == 1 ) {
- my $irq = $irqmap->{$ifname};
- assign_single( $ifname, $irq) if $irq;
- } elsif ($numirq > 1) {
- # Special case for paired Rx and Tx
- my @mirq = grep { /^$ifname-rx-/ } @irqnames;
- my $num_mirq = scalar(@mirq);
- if ( $num_mirq > 0 ) {
- assign_multiqueue( $ifname, $irqmap, @mirq );
-
- @mirq = grep { /^$ifname-tx-/ } @irqnames;
- assign_multiqueue( $ifname, $irqmap, @mirq );
- return;
- }
-
- # Normal case for single irq per queue
- @mirq = grep { /^$ifname-/ } @irqnames;
- $num_mirq = scalar(@mirq);
- if ( $num_mirq > 0 ) {
- assign_multiqueue( $ifname, $irqmap, @mirq );
- return;
- }
-
- # Netxen thought up yet another convention
- @mirq = grep { /^$ifname\[/ } @irqnames;
- if ( $#mirq > 0 ) {
- assign_multiqueue( $ifname, $irqmap, @mirq );
- return;
- }
-
- syslog(LOG_ERR, "%s: Unknown multiqueue irq naming: %s\n", $ifname,
- join(' ', @irqnames));
- }
-}
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