vhost: add power monitor API

[dpdk.git] / doc / guides / prog_guide / pdump_lib.rst

diff --git a/doc/guides/prog_guide/pdump_lib.rst b/doc/guides/prog_guide/pdump_lib.rst
index ed3c15e..07b9f39 100644 (file)
--- a/doc/guides/prog_guide/pdump_lib.rst
+++ b/doc/guides/prog_guide/pdump_lib.rst
@@ -1,29 +1,39 @@
 ..  SPDX-License-Identifier: BSD-3-Clause
     Copyright(c) 2016 Intel Corporation.
 
 ..  SPDX-License-Identifier: BSD-3-Clause
     Copyright(c) 2016 Intel Corporation.
 

-.. _pdump_library:
+Packet Capture Library
+======================

 
 

-The librte_pdump Library
-========================
-
-The ``librte_pdump`` library provides a framework for packet capturing in DPDK.
+The DPDK ``pdump`` library provides a framework for packet capturing in DPDK.

 The library does the complete copy of the Rx and Tx mbufs to a new mempool and
 hence it slows down the performance of the applications, so it is recommended
 to use this library for debugging purposes.
 
 The library does the complete copy of the Rx and Tx mbufs to a new mempool and
 hence it slows down the performance of the applications, so it is recommended
 to use this library for debugging purposes.
 

+The library uses a generic multi process channel to facilitate communication
+between primary and secondary process for enabling/disabling packet capture on
+ports.
+

 The library provides the following APIs to initialize the packet capture framework, to enable
 The library provides the following APIs to initialize the packet capture framework, to enable

-or disable the packet capture, and to uninitialize it:
+or disable the packet capture, and to uninitialize it.

 
 * ``rte_pdump_init()``:
   This API initializes the packet capture framework.
 
 * ``rte_pdump_enable()``:
   This API enables the packet capture on a given port and queue.
 
 * ``rte_pdump_init()``:
   This API initializes the packet capture framework.
 
 * ``rte_pdump_enable()``:
   This API enables the packet capture on a given port and queue.

-  Note: The filter option in the API is a place holder for future enhancements.
+
+* ``rte_pdump_enable_bpf()``
+  This API enables the packet capture on a given port and queue.
+  It also allows setting an optional filter using DPDK BPF interpreter
+  and setting the captured packet length.

 
 * ``rte_pdump_enable_by_deviceid()``:
   This API enables the packet capture on a given device id (``vdev name or pci address``) and queue.
 
 * ``rte_pdump_enable_by_deviceid()``:
   This API enables the packet capture on a given device id (``vdev name or pci address``) and queue.

-  Note: The filter option in the API is a place holder for future enhancements.
+
+* ``rte_pdump_enable_bpf_by_deviceid()``
+  This API enables the packet capture on a given device id (``vdev name or pci address``) and queue.
+  It also allows setting an optional filter using DPDK BPF interpreter
+  and setting the captured packet length.

 
 * ``rte_pdump_disable()``:
   This API disables the packet capture on a given port and queue.
 
 * ``rte_pdump_disable()``:
   This API disables the packet capture on a given port and queue.


@@ -34,63 +44,50 @@ or disable the packet capture, and to uninitialize it:
 * ``rte_pdump_uninit()``:
   This API uninitializes the packet capture framework.
 
 * ``rte_pdump_uninit()``:
   This API uninitializes the packet capture framework.
 

-* ``rte_pdump_set_socket_dir()``:
-  This API sets the server and client socket paths.
-  Note: This API is not thread-safe.
-

 
 Operation
 ---------
 
 
 Operation
 ---------
 

-The ``librte_pdump`` library works on a client/server model. The server is responsible for enabling or
-disabling the packet capture and the clients are responsible for requesting the enabling or disabling of
-the packet capture.
-
-The packet capture framework, as part of its initialization, creates the pthread and the server socket in
-the pthread. The application that calls the framework initialization will have the server socket created,
-either under the path that the application has passed or under the default path i.e. either ``/var/run/.dpdk`` for
-root user or ``~/.dpdk`` for non root user.
-
-Applications that request enabling or disabling of the packet capture will have the client socket created either under
-the path that the application has passed or under the default path i.e. either ``/var/run/.dpdk`` for root user or
-``~/.dpdk`` for not root user to send the requests to the server. The server socket will listen for client requests for
-enabling or disabling the packet capture.
-
+The primary process using ``librte_pdump`` is responsible for initializing the packet
+capture framework. The packet capture framework, as part of its initialization, creates the
+multi process channel to facilitate communication with secondary process, so the
+secondary process ``app/pdump`` tool is responsible for enabling and disabling the packet capture on ports.

 
 Implementation Details
 ----------------------
 
 
 Implementation Details
 ----------------------
 

-The library API ``rte_pdump_init()``, initializes the packet capture framework by creating the pthread and the server
-socket. The server socket in the pthread context will be listening to the client requests to enable or disable the
-packet capture.
+The library API ``rte_pdump_init()``, initializes the packet capture framework by creating the multi process
+channel using ``rte_mp_action_register()`` API. The primary process will listen to secondary process requests
+to enable or disable the packet capture over the multi process channel.

 
 The library APIs ``rte_pdump_enable()`` and ``rte_pdump_enable_by_deviceid()`` enables the packet capture.
 
 The library APIs ``rte_pdump_enable()`` and ``rte_pdump_enable_by_deviceid()`` enables the packet capture.

-On each call to these APIs, the library creates a separate client socket, creates the "pdump enable" request and sends
-the request to the server. The server that is listening on the socket will take the request and enable the packet capture
-by registering the Ethernet RX and TX callbacks for the given port or device_id and queue combinations.
-Then the server will mirror the packets to the new mempool and enqueue them to the rte_ring that clients have passed
-to these APIs. The server also sends the response back to the client about the status of the request that was processed.
-After the response is received from the server, the client socket is closed.
+For the calls to these APIs from secondary process, the library creates the "pdump enable" request and sends
+the request to the primary process over the multi process channel. The primary process takes this request
+and enables the packet capture by registering the Ethernet RX and TX callbacks for the given port or device_id
+and queue combinations. Then the primary process will mirror the packets to the new mempool and enqueue them to
+the rte_ring that secondary process have passed to these APIs.
+
+The packet ring supports one of two formats.
+The default format enqueues copies of the original packets into the rte_ring.
+If the ``RTE_PDUMP_FLAG_PCAPNG`` is set, the mbuf data is extended
+with header and trailer to match the format of Pcapng enhanced packet block.
+The enhanced packet block has meta-data such as the timestamp, port and queue
+the packet was captured on.
+It is up to the application consuming the packets from the ring
+to select the format desired.

 
 The library APIs ``rte_pdump_disable()`` and ``rte_pdump_disable_by_deviceid()`` disables the packet capture.
 
 The library APIs ``rte_pdump_disable()`` and ``rte_pdump_disable_by_deviceid()`` disables the packet capture.

-On each call to these APIs, the library creates a separate client socket, creates the "pdump disable" request and sends
-the request to the server. The server that is listening on the socket will take the request and disable the packet
-capture by removing the Ethernet RX and TX callbacks for the given port or device_id and queue combinations. The server
-also sends the response back to the client about the status of the request that was processed. After the response is
-received from the server, the client socket is closed.
-
-The library API ``rte_pdump_uninit()``, uninitializes the packet capture framework by closing the pthread and the
-server socket.
+For the calls to these APIs from secondary process, the library creates the "pdump disable" request and sends
+the request to the primary process over the multi process channel. The primary process takes this request and
+disables the packet capture by removing the Ethernet RX and TX callbacks for the given port or device_id and
+queue combinations.

 
 

-The library API ``rte_pdump_set_socket_dir()``, sets the given path as either server socket path
-or client socket path based on the ``type`` argument of the API.
-If the given path is ``NULL``, default path will be selected, i.e. either ``/var/run/.dpdk`` for root user or ``~/.dpdk``
-for non root user. Clients also need to call this API to set their server socket path if the server socket
-path is different from default path.
+The library API ``rte_pdump_uninit()``, uninitializes the packet capture framework by calling ``rte_mp_action_unregister()``
+function.

 
 
 Use Case: Packet Capturing
 --------------------------
 
 
 
 Use Case: Packet Capturing
 --------------------------
 

-The DPDK ``app/pdump`` tool is developed based on this library to capture packets in DPDK.
-Users can use this as an example to develop their own packet capturing tools.
+The DPDK ``app/dpdk-dumpcap`` utility uses this library
+to capture packets in DPDK.