docs: networking: convert pktgen.txt to ReST

- add SPDX header;
- adjust title markup;
- use bold markups on a few places;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines where needed;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/index.rst

@@ -91,6 +91,7 @@ Contents:
    operstates
    packet_mmap
    phonet
+   pktgen
 
 .. only::  subproject and html
 

Documentation/networking/pktgen.rst

@@ -1,7 +1,8 @@
+.. SPDX-License-Identifier: GPL-2.0
 
-
+====================================
 HOWTO for the linux packet generator
-                  ------------------------------------
+====================================
 
 Enable CONFIG_NET_PKTGEN to compile and build pktgen either in-kernel
 or as a module.  A module is preferred; modprobe pktgen if needed.  Once
@@ -9,14 +10,15 @@ running, pktgen creates a thread for each CPU with affinity to that CPU.
 Monitoring and controlling is done via /proc.  It is easiest to select a
 suitable sample script and configure that.
 
-On a dual CPU:
+On a dual CPU::
 
     ps aux | grep pkt
     root       129  0.3  0.0     0    0 ?        SW    2003 523:20 [kpktgend_0]
     root       130  0.3  0.0     0    0 ?        SW    2003 509:50 [kpktgend_1]
 
 
-For monitoring and control pktgen creates:
+For monitoring and control pktgen creates::
+
 	/proc/net/pktgen/pgctrl
 	/proc/net/pktgen/kpktgend_X
 	/proc/net/pktgen/ethX
@@ -28,7 +30,8 @@ Tuning NIC for max performance
 The default NIC settings are (likely) not tuned for pktgen's artificial
 overload type of benchmarking, as this could hurt the normal use-case.
 
-Specifically increasing the TX ring buffer in the NIC:
+Specifically increasing the TX ring buffer in the NIC::
+
  # ethtool -G ethX tx 1024
 
 A larger TX ring can improve pktgen's performance, while it can hurt
@@ -46,7 +49,8 @@ This cleanup issue is specifically the case for the driver ixgbe
 and the cleanup interval is affected by the ethtool --coalesce setting
 of parameter "rx-usecs".
 
-For ixgbe use e.g. "30" resulting in approx 33K interrupts/sec (1/30*10^6):
+For ixgbe use e.g. "30" resulting in approx 33K interrupts/sec (1/30*10^6)::
+
  # ethtool -C ethX rx-usecs 30
 
 
@@ -55,7 +59,7 @@ Kernel threads
 Pktgen creates a thread for each CPU with affinity to that CPU.
 Which is controlled through procfile /proc/net/pktgen/kpktgend_X.
 
-Example: /proc/net/pktgen/kpktgend_0
+Example: /proc/net/pktgen/kpktgend_0::
 
  Running:
  Stopped: eth4@0
@@ -64,6 +68,7 @@ Example: /proc/net/pktgen/kpktgend_0
 Most important are the devices assigned to the thread.
 
 The two basic thread commands are:
+
  * add_device DEVICE@NAME -- adds a single device
  * rem_device_all         -- remove all associated devices
 
@@ -83,7 +88,7 @@ Viewing devices
 
 The Params section holds configured information.  The Current section
 holds running statistics.  The Result is printed after a run or after
-interruption.  Example:
+interruption.  Example::
 
     /proc/net/pktgen/eth4@0
 
@@ -114,11 +119,12 @@ Configuring devices
 This is done via the /proc interface, and most easily done via pgset
 as defined in the sample scripts.
 You need to specify PGDEV environment variable to use functions from sample
-scripts, i.e.:
+scripts, i.e.::
+
     export PGDEV=/proc/net/pktgen/eth4@0
     source samples/pktgen/functions.sh
 
-Examples:
+Examples::
 
  pg_ctrl start           starts injection.
  pg_ctrl stop            aborts injection. Also, ^C aborts generator.
@@ -232,10 +238,14 @@ A collection of tutorial scripts and helpers for pktgen is in the
 samples/pktgen directory. The helper parameters.sh file support easy
 and consistent parameter parsing across the sample scripts.
 
-Usage example and help:
+Usage example and help::
+
  ./pktgen_sample01_simple.sh -i eth4 -m 00:1B:21:3C:9D:F8 -d 192.168.8.2
 
-Usage: ./pktgen_sample01_simple.sh [-vx] -i ethX
+Usage:::
+
+  ./pktgen_sample01_simple.sh [-vx] -i ethX
+
   -i : ($DEV)       output interface/device (required)
   -s : ($PKT_SIZE)  packet size
   -d : ($DEST_IP)   destination IP
@@ -250,7 +260,7 @@ The global variables being set are also listed.  E.g. the required
 interface/device parameter "-i" sets variable $DEV.  Copy the
 pktgen_sampleXX scripts and modify them to fit your own needs.
 
-The old scripts:
+The old scripts::
 
     pktgen.conf-1-2                  # 1 CPU 2 dev
     pktgen.conf-1-1-rdos             # 1 CPU 1 dev w. route DoS
@@ -271,7 +281,7 @@ to the running threads CPU (directly from smp_processor_id()).
 Enable IPsec
 ============
 Default IPsec transformation with ESP encapsulation plus transport mode
-can be enabled by simply setting:
+can be enabled by simply setting::
 
     pgset "flag IPSEC"
     pgset "flows 1"
@@ -284,19 +294,19 @@ to employ.
 Current commands and configuration options
 ==========================================
 
-** Pgcontrol commands:
+**Pgcontrol commands**::
 
     start
     stop
     reset
 
-** Thread commands:
+**Thread commands**::
 
     add_device
     rem_device_all
 
 
-** Device commands:
+**Device commands**::
 
     count
     clone_skb
@@ -386,13 +396,15 @@ svlan_p
 
 
 References:
-ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/
+
-ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/
+- ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/
+- tp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/
 
 Paper from Linux-Kongress in Erlangen 2004.
-ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf
+- ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf
 
 Thanks to:
+
 Grant Grundler for testing on IA-64 and parisc, Harald Welte,  Lennert Buytenhek
 Stephen Hemminger, Andi Kleen, Dave Miller and many others.
 

net/Kconfig

@@ -344,7 +344,7 @@ config NET_PKTGEN
 	  what was just said, you don't need it: say N.
 
 	  Documentation on how to use the packet generator can be found
-	  at <file:Documentation/networking/pktgen.txt>.
+	  at <file:Documentation/networking/pktgen.rst>.
 
 	  To compile this code as a module, choose M here: the
 	  module will be called pktgen.

net/core/pktgen.c

@@ -56,7 +56,7 @@
  * Integrated to 2.5.x 021029 --Lucio Maciel (luciomaciel@zipmail.com.br)
  *
  * 021124 Finished major redesign and rewrite for new functionality.
- * See Documentation/networking/pktgen.txt for how to use this.
+ * See Documentation/networking/pktgen.rst for how to use this.
  *
  * The new operation:
  * For each CPU one thread/process is created at start. This process checks

samples/pktgen/README.rst

@@ -3,7 +3,7 @@ Sample and benchmark scripts for pktgen (packet generator)
 This directory contains some pktgen sample and benchmark scripts, that
 can easily be copied and adjusted for your own use-case.
 
-General doc is located in kernel: Documentation/networking/pktgen.txt
+General doc is located in kernel: Documentation/networking/pktgen.rst
 
 Helper include files
 ====================