On 16-06-30 01:23 AM, Jesper Dangaard Brouer wrote:

On Wed, 29 Jun 2016 13:03:26 -0700
John Fastabend [off-list ref] wrote:

quoted

This adds samples for pktgen to use with new mode to inject pkts into
the qdisc layer. This also doubles as nice test cases to test any
patches against qdisc layer.

[...]

quoted

+#
+# Benchmark script:
+#  - developed for benchmarking egress qdisc path, derived from
+#    ingress benchmark script.
+#

As you probably gathered 'derived' is giving me too much credit here
its more like cut'n'pasted from ingress benchmark scrip :)

quoted

+# Script for injecting packets into egress qdisc path of the stack
+# with pktgen "xmit_mode queue_xmit".
+#
+basedir=`dirname $0`
+source ${basedir}/functions.sh
+root_check_run_with_sudo "$@"
+
+# Parameter parsing via include
+source ${basedir}/parameters.sh
+# Using invalid DST_MAC will cause the packets to get dropped in
+# ip_rcv() which is part of the test
+[ -z "$DEST_IP" ] && DEST_IP="198.18.0.42"
+[ -z "$DST_MAC" ] && DST_MAC="90:e2:ba:ff:ff:ff"
+
+# Burst greater than 1 are invalid but allow users to specify it and
+# get an error instead of silently ignoring it.
+[ -z "$BURST" ] && BURST=1

In other scripts I've rejected this at this step, instead of depending
on failure when sending the burst option to pktgen. Like:

https://github.com/netoptimizer/network-testing/blob/master/pktgen/pktgen_sample04_many_flows.sh#L31-L33

Agreed that is nicer. I had originally left it to make sure I was
catching the burst > 1 case in pktgen but will remove.

quoted

+
+# Base Config
+DELAY="0"        # Zero means max speed
+COUNT="10000000" # Zero means indefinitely
+
+# General cleanup everything since last run
+pg_ctrl "reset"
+
+# Threads are specified with parameter -t value in $THREADS
+for ((thread = 0; thread < $THREADS; thread++)); do
+    # The device name is extended with @name, using thread number to
+    # make then unique, but any name will do.
+    dev=${DEV}@${thread}
+
+    # Add remove all other devices and add_device $dev to thread
+    pg_thread $thread "rem_device_all"
+    pg_thread $thread "add_device" $dev
+
+    # Base config of dev
+    pg_set $dev "flag QUEUE_MAP_CPU"
+    pg_set $dev "count $COUNT"
+    pg_set $dev "pkt_size $PKT_SIZE"
+    pg_set $dev "delay $DELAY"
+    pg_set $dev "flag NO_TIMESTAMP"
+
+    # Destination
+    pg_set $dev "dst_mac $DST_MAC"
+    pg_set $dev "dst $DEST_IP"
+
+    # Inject packet into RX path of stack

Hmmm, maybe above comment need to be adjusted...

Yep.

quoted

+    pg_set $dev "xmit_mode queue_xmit"
+
+    # Burst allow us to avoid measuring SKB alloc/free overhead

This comment is confusing, maybe just remove. Didn't think burst is a
valid use-case.

Yep.