Bugfix: 2189

Add config node to configure NIC interrupt CPU affinity on SMPs.

1 files changed, 139 insertions, 0 deletions

diff --git a/scripts/vyatta-irqaffin b/scripts/vyatta-irqaffin
new file mode 100644
index 0000000..6650175
--- /dev/null
+++ b/scripts/vyatta-irqaffin
@@ -0,0 +1,139 @@
+#!/bin/bash
+#
+# CLI back-end script to manipulate NIC interrupt CPU affinity.
+#
+# Provides sub-commands to:
+#   - Check the validity of an interface name and affinity mask value
+#   - Set the affinity mask to the IRQ being used by an interface
+#   - Reset the affinity mask of the IRQ being used by an interface to the
+#     system default value of all-ones.
+#   - Print the affinity mask of the IRQ being used by an interface
+#
+
+# The default "all-ones" IRQ affinity mask.  Used in the "reset" sub-command.
+DEFAULT_MASK=ffff
+
+# Max number of hex characters in an IRQ affinity mask.  Support up to 16 CPUs.
+MAX_MASK=4
+
+print_usage()
+{
+    echo "Usage:"
+    echo -e "\t$0 check <ifname> <mask>"
+    echo -e "\t$0 set <ifname> <mask>"
+    echo -e "\t$0 reset <ifname>"
+    echo -e "\t$0 print <ifname>"
+}
+
+get_irqnum()
+{
+    irqnum=`find /proc/irq -name $1 -print | awk -F / '{ print $4 }'`
+    if [ -z "$irqnum" ]; then
+	echo "Invalid interface name: $1"
+	return 1
+    fi
+    return 0
+}
+
+
+get_mask()
+{
+    mask=$1
+    # mask must be a short hex value
+    if [ ${#mask} -gt $MAX_MASK ]; then
+	echo "mask too long: ${#2} characters."
+	return 1
+    fi
+
+    # strip out all the hex digits
+    exmask=`echo $mask | sed -e s/[0-9a-f]//g`
+
+    # if anything is left, its not hex
+    if [ ! -z "$exmask" ]; then
+	echo "Invalid characters in hex mask: $exmask"
+	return 1
+    fi
+    return 0
+}
+
+case "$1" in
+    check)
+	if [ $# -ne 3 ]; then
+		print_usage
+		exit 1
+	fi
+
+	if ! get_irqnum $2 ; then
+	    exit 1
+	fi
+
+	if ! get_mask $3 ; then
+	    exit 1
+	fi
+	exit 0
+	;;
+
+    set)
+	if [ $# -ne 3 ]; then
+		print_usage
+		exit 1
+	fi
+	if ! get_irqnum $2 ; then
+	    exit 1
+	fi
+
+	if ! get_mask $3 ; then
+	    exit 1
+	fi
+
+	echo $mask > /proc/irq/$irqnum/smp_affinity
+
+	if [ $? -ne 0 ]; then
+	    echo "Couldn't assign smp_affinity.  Exit status: $?"
+	    exit 1
+	fi
+	;;
+
+    reset)
+	if [ $# -ne 2 ]; then
+		print_usage
+		exit 1
+	fi
+	if ! get_irqnum $2 ; then
+	    exit 1
+	fi
+
+	echo $DEFAULT_MASK > /proc/irq/$irqnum/smp_affinity
+	if [ $? -ne 0 ]; then
+	    echo "Couldn't assign smp_affinity.  Exit status: $?"
+	    exit 1
+	fi
+	;;
+     
+
+    print)
+	if [ $# -ne 2 ]; then
+		print_usage
+		exit 1
+	fi
+	if ! get_irqnum $2 ; then
+	    exit 1
+	fi
+
+	mask=`cat /proc/irq/$irqnum/smp_affinity`
+	
+	if [ -z $mask ]; then
+	    echo "Couldn't get smp_affinity for interface $2, irq $irqnum"
+	    exit 1
+	fi
+
+	echo "Interface $2 is using IRQ: $irqnum"
+	echo "SMP affinity mask for IRQ $irqnum is: $mask"
+	;;
+
+    *)
+	print_usage
+	exit 1
+	;;
+	
+esac