From c8c80d23b8d76ae642293e06fb487de2b3152fa9 Mon Sep 17 00:00:00 2001 From: Joseph Henry Date: Tue, 6 Dec 2016 14:00:28 -0800 Subject: [PATCH] Updated rx/tx doc --- docs/rxtx.md | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/docs/rxtx.md b/docs/rxtx.md index 3e5030a..ccee7ba 100644 --- a/docs/rxtx.md +++ b/docs/rxtx.md @@ -8,42 +8,39 @@ How Data is Sent and Received by an App using the SDK The **tap service** monitors incoming packets, when one destined for us is detected it notifies the **stack driver** via `put()`. Then `pico_rx()` is called, its job is to re-encapsulate the ethernet frame and copy it onto the guarded `pico_frame_rxbuf`. This buffer is guarded because it is accessed via the **tap service** thread and the **network stack** thread. ``` -SERVICE_THREAD wire put() pico_rx() ---> ``` -Periodically the stack thread will call `pico_eth_poll()`, this is responsible for reading the frames from the aformentioned RX I/O frame buffer and feeding it into the stack via `pico_stack_recv()`. +Periodically the **network stack** thread will call `pico_eth_poll()`, this is responsible for reading the frames from the aformentioned `pico_frame_rxbuf` and feeding it into the stack via `pico_stack_recv()`. ``` -STACK_THREAD pico_eth_poll() ---> pico_stack_recv ``` -After some time has passed and the stack has processed the incoming frames a `PICO_SOCK_EV_RD` event will be triggered which calls `pico_cb_socket_activity()`, and ultimately `pico_cb_tcp_read()`. This is where we copy the incoming data from the `pico_socket` to the `Connection`'s `rxbuf`. We then notify the ZeroTier tap service that the `PhySocket` (a wrapped file descriptor with one end visible to the application) associated with with this `Connection` has data in the `rxbuf` that needs to be written to it. +After some time has passed and the **network stack** has processed the incoming frames a `PICO_SOCK_EV_RD` event will be triggered which calls `pico_cb_socket_activity()`, and ultimately `pico_cb_tcp_read()`. This is where we copy the incoming data from the `pico_socket` to the `Connection`'s `rxbuf` (different from `pico_frame_rxbuf`). We then notify the **tap service** that the `PhySocket` (a wrapped file descriptor with one end visible to the application) associated with this `Connection` has data in its `rxbuf` that needs to be written so the app can read it. ``` -STACK_THREAD pico_cb_socket_activity() pico_cb_tcp_read() ---> conn->rxbuf setNotifyWritable=TRUE ``` -After some (more) time, the ZeroTier tap service thread will call `pico_handleRead()`, this will copy the data from the `rxbuf` to the `AF_UNIX` socket which links the service and your application. After this point it's up to you application to read the data via a conventional `read()`, `recv()`, or `recvfrom()` call. +After some (more) time, the **tap service** thread will call `pico_handleRead()`, this will copy the data from the `rxbuf` to the `AF_UNIX` socket which links the service and your application. ``` -SERVICE_THREAD -pico_handleRead()x +pico_handleRead() streamSend(): conn->rxbuf --- conn->sock ``` -... +After this point it's up to your application to read the data via a conventional `read()`, `recv()`, or `recvfrom()` call. +``` +read() +``` -APP_THREAD - read() ***