pktgen: cleanups and introducing new samples/pktgen scripts

v3:
- Aborted v2 send due it was not generating diff stat (this is a bug in stg-mail, if not in the root directory)

v2: address nitpicks from Cong Wang
- Remove useless cat's, but keep them for old pgset()
- Comment on: Due to pgctrl, cannot use exit code $? from grep
- Use arithmetic compare in pktgen_sample03_burst_single_flow.sh

This patchset is focused on making pktgen easier to use and better documented. It contains a number of documentation updates and minor changes to pktgen. The major contribution is introduction of common helper function for sample scripts.

Instead of the old pgset() function, three new shell functions for configuring the different components of pktgen are introduced:
pg_ctrl(), pg_thread() and pg_set().

The new functions correspond to pktgens different components.
* pg_ctrl() control "pgctrl" (/proc/net/pktgen/pgctrl)
* pg_thread() control the kernel threads and binding to devices
* pg_set() control setup of individual devices

Helpers also provide consistent parameter parsing across the sample scripts.

Usage example:
./pktgen_sample01_simple.sh -i eth41 -m 00:12:C0:02:AC:5A -d 192.168.41.2

Usage: ./pktgen_sample01_simple.sh [-vx] -i ethX

  -i : ($DEV)       output interface/device (required)
  -s : ($PKT_SIZE)  packet size
  -d : ($DEST_IP)   destination IP
  -m : ($DST_MAC)   destination MAC-addr
  -t : ($THREADS)   threads to start
  -c : ($SKB_CLONE) SKB clones send before alloc new SKB
  -b : ($BURST)     HW level bursting of SKBs
  -v : ($VERBOSE)   verbose
  -x : ($DEBUG)     debug

These scripts are borrowed from:
https://github.com/netoptimizer/network-testing/tree/master/pktgen

---

Jesper Dangaard Brouer (10):
pktgen: add benchmark script pktgen_bench_xmit_mode_netif_receive.sh
pktgen: add sample script pktgen_sample03_burst_single_flow.sh
pktgen: add sample script pktgen_sample02_multiqueue.sh
pktgen: add sample script pktgen_sample01_simple.sh
pktgen: new pktgen helper functions for samples scripts
pktgen: make /proc/net/pktgen/pgctrl report fail on invalid input
pktgen: document ability to add same device to several threads
pktgen: doc were missing several config options
pktgen: adjust spacing in proc file interface output
pktgen: remove obsolete "max_before_softirq" from pktgen doc

 Documentation/networking/pktgen.txt                |  141 ++++++++++++++------
 net/core/pktgen.c                                  |    6 -
 samples/pktgen/README.rst                          |   43 ++++++
 samples/pktgen/functions.sh                        |  121 +++++++++++++++++
 samples/pktgen/parameters.sh                       |   97 ++++++++++++++
 samples/pktgen/pktgen.conf-1-1                     |   59 --------
 samples/pktgen/pktgen.conf-2-1                     |   66 ---------
 samples/pktgen/pktgen.conf-2-2                     |   73 ----------
 .../pktgen/pktgen_bench_xmit_mode_netif_receive.sh |   86 ++++++++++++
 samples/pktgen/pktgen_sample01_simple.sh           |   71 ++++++++++
 samples/pktgen/pktgen_sample02_multiqueue.sh       |   75 +++++++++++
 .../pktgen/pktgen_sample03_burst_single_flow.sh    |   82 ++++++++++++
 12 files changed, 678 insertions(+), 242 deletions(-)
 create mode 100644 samples/pktgen/README.rst
 create mode 100644 samples/pktgen/functions.sh
 create mode 100644 samples/pktgen/parameters.sh
 delete mode 100755 samples/pktgen/pktgen.conf-1-1
 delete mode 100755 samples/pktgen/pktgen.conf-2-1
 delete mode 100755 samples/pktgen/pktgen.conf-2-2
 create mode 100755 samples/pktgen/pktgen_bench_xmit_mode_netif_receive.sh
 create mode 100755 samples/pktgen/pktgen_sample01_simple.sh
 create mode 100755 samples/pktgen/pktgen_sample02_multiqueue.sh
 create mode 100755 samples/pktgen/pktgen_sample03_burst_single_flow.sh