Squashed commit of the following:
Fix up some final compile isses.
net/netdev: Convert the network down notification logic to use the new wqueue-based notification factility.
net/udp: Convert the UDP readahead notification logic to use the new wqueue-based notification factility.
net/tcp: Convert the TCP readahead notification logic to use the new wqueue-based notification factility.
mm/iob: Convert the IOB notification logic to use the new wqueue-based notification factility.
sched/wqueue: Signals are not good IPCs to support the target poll functionality for several reasons including the amount of data that can be passed with a signal and in the fact that in protected and kernel modes, user threads executing signal handlers in protected, kernel memory is problematic. Instead, convert the same logic to perform the notifications via function callback on the high priority work queue.
Squashed commit of the following:
net/tcp: Add signal notification for the case when UDP read-ahead data is buffered. This is basically of clone of the TCP notification logic with naming adapted for UDP.
net/tcp: Add signal notification for the case when TCP read-ahead data is buffered.
Fix a few typo/compilation problems.
net/: Remove all CONFIG_NET_xxx_TCP_RECVWNDO configuration variables. They were used only to initialize the d_recwndo of the network device structure which no longer exists.
net/: Remove the device TCP receive window field (d_recvwndo) from the device structure. That value is no longer retained, but is calculated dynamically.
Remove some dangling references to CONFIG_NET_TCP_RWND_CONTROL.
net/tcp: Take read-ahead throttling into account when calculating the TCP receive window size.
net/tcp: tcp_get_recvwindow() now returns the receive window size directly (vs. indirectly via the device structure).
net/tcp: Remove CONFIG_NET_TCP_RWND_CONTROL. TCP window algorithm is now trigged only by CONFIG_NET_TCP_READAHEAD.
Squashed commit of the following:
sched: Rename all use of system_t to clock_t.
syscall: Rename all use of system_t to clock_t.
net: Rename all use of system_t to clock_t.
libs: Rename all use of system_t to clock_t.
fs: Rename all use of system_t to clock_t.
drivers: Rename all use of system_t to clock_t.
arch: Rename all use of system_t to clock_t.
include: Remove definition of systime_t; rename all use of system_t to clock_t.
net/tcp: Add logic to send probes when SO_KEEPALIVE is enabled.
net/tcp: TCP socket should not have to be connected to configure KeepAlive.
net/: Add a separate configuration to enable/disable KEEPALIVE socket options.
net/tcp: Arguments to TCP keep-alive timing functions probably should be struct timeval as are the times for other time-related socket options.
net/tcp: Fix a backward conditional
net/tcp: Add some more checks and debug output to TCP-protocol socket options.
net/tcp: Cosmetic changes to some alignment.
net/: Adds socket options needed to manage TCP-keepalive and TCP state machine logic to detect if that the remote peer is alive. Still missing the timer poll logic to send the keep-alive probes and the state machine logic to respond to probes.
User-space networking stack API allows user-space daemon to
provide TCP/IP stack implementation for NuttX network.
Main use for this is to allow use and seamless integration of
HW-provided TCP/IP stacks to NuttX.
For example, user-space daemon can translate /dev/usrsock
API requests to HW TCP/IP API requests while rest of the
user-space can access standard socket API, with socket
descriptors that can be used with NuttX system calls.
When a poll requesting POLLOUT happens, the poll should return
immediately if a write will not block. This change adds that, as
opposed to the old behaviour of blocking until a timer from the
Ethernet driver eventually triggers the poll to complete.
This is only implemented for buffered TCP. Unbuffered TCP should
behave as before.
The solution here is to eliminate the device devices semaphore altogether. This eliminates netdev_semtake() and netdev_semgive() and replaces them with net_lock() and net_unlock() which have larger scope as needed for this purpose.
