Imported Upstream version 16.04

Change-Id: I77eadcd8538a9122e4773cbe55b24033dc451757
Signed-off-by: C.J. Collier <cjcollier@linuxfoundation.org>

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+..  BSD LICENSE
+    Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+
+    * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+    * Neither the name of Intel Corporation nor the names of its
+    contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Hello World Sample Application
+==============================
+
+The Hello World sample application is an example of the simplest DPDK application that can be written.
+The application simply prints an "helloworld" message on every enabled lcore.
+
+Compiling the Application
+-------------------------
+
+#.  Go to the example directory:
+
+    .. code-block:: console
+
+        export RTE_SDK=/path/to/rte_sdk
+        cd ${RTE_SDK}/examples/helloworld
+
+#.  Set the target (a default target is used if not specified). For example:
+
+    .. code-block:: console
+
+        export RTE_TARGET=x86_64-native-linuxapp-gcc
+
+    See the *DPDK Getting Started* Guide for possible RTE_TARGET values.
+
+#.  Build the application:
+
+    .. code-block:: console
+
+        make
+
+Running the Application
+-----------------------
+
+To run the example in a linuxapp environment:
+
+.. code-block:: console
+
+    $ ./build/helloworld -c f -n 4
+
+Refer to *DPDK Getting Started Guide* for general information on running applications
+and the Environment Abstraction Layer (EAL) options.
+
+Explanation
+-----------
+
+The following sections provide some explanation of code.
+
+EAL Initialization
+~~~~~~~~~~~~~~~~~~
+
+The first task is to initialize the Environment Abstraction Layer (EAL).
+This is done in the main() function using the following code:
+
+.. code-block:: c
+
+    int
+
+    main(int argc, char **argv)
+
+    {
+        ret = rte_eal_init(argc, argv);
+        if (ret < 0)
+            rte_panic("Cannot init EAL\n");
+
+This call finishes the initialization process that was started before main() is called (in case of a Linuxapp environment).
+The argc and argv arguments are provided to the rte_eal_init() function.
+The value returned is the number of parsed arguments.
+
+Starting Application Unit Lcores
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Once the EAL is initialized, the application is ready to launch a function on an lcore.
+In this example, lcore_hello() is called on every available lcore.
+The following is the definition of the function:
+
+.. code-block:: c
+
+    static int
+    lcore_hello( attribute ((unused)) void *arg)
+    {
+        unsigned lcore_id;
+
+        lcore_id = rte_lcore_id();
+        printf("hello from core %u\n", lcore_id);
+        return 0;
+    }
+
+The code that launches the function on each lcore is as follows:
+
+.. code-block:: c
+
+    /* call lcore_hello() on every slave lcore */
+
+    RTE_LCORE_FOREACH_SLAVE(lcore_id) {
+       rte_eal_remote_launch(lcore_hello, NULL, lcore_id);
+    }
+
+    /* call it on master lcore too */
+
+    lcore_hello(NULL);
+
+The following code is equivalent and simpler:
+
+.. code-block:: c
+
+    rte_eal_mp_remote_launch(lcore_hello, NULL, CALL_MASTER);
+
+Refer to the *DPDK API Reference* for detailed information on the rte_eal_mp_remote_launch() function.