In the current net stack implementation, there is no mechanism
for notifying the loss of the wireless connection, if the network
is disconnected then application sends data packets through tcp,
the tcp_timer will keep retrying fetch the ack for awhile, the
connection status will not be able to be switched timely.
Change-Id: I84d1121527edafc6ee6ad56ba164838694e7e11c
Signed-off-by: chao.an <anchao@xiaomi.com>
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
Squashed commit of the following:
sched/sched/sched_getsockets.c: Fix an error in conditional compilation.
fs/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
Documentation/: Remove all references to CONFIG_NSOCKET_DESCRIPTORS == 0
include/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
libs/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
net/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
sched/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
syscall/: Remove all conditional logic based on CONFIG_NSOCKET_DESCRIPTORS == 0
tools/: Fixups for CONFIG_NSOCKET_DESCRIPTORS no longer used to disable sockets.
net/mld: The MLD logic now compiles and is much less toxic. It still is not a proper MLD implementation: (1) It is basically a port of IGMP, tweaked to work with IPv6 and ICMPv6 MLD messages, (2) it needs a proper analysis and comparison with RFC 3810, and (3) it is completely untested. For this reason, it will remain EXPERIMENTAL for some time.
net/mld: Add some missing macros, more fixes related to IPv6 vs IPv4 types,
net/mld: More compilation cleaning. Most fixups for IPv6 vs IPv4 types.
net/mld: Hook crudely converted .c files into build system and resolve a few of the many, many compilation/design problems.
net/mld: Add support for MLD statistics.
net/mld: Hook in MLD poll and packet transmission logic.
net/mld: Change references to IPv4 definitions to IPv6 definitions; Remove mld_input() since MLD piggybacks on ICMPv6 input. Add functions to catch MLD messages dispatched by ICMPv6 input logic.
net/mld: As a starting point, copy all net/igmp/*.c files to net/mld/. and change all occurrences of igmp (or IGMP) to mld (or MLD).
net/mld: More compilation cleaning. Most fixups for IPv6 vs IPv4 types.
net/mld: Hook crudely converted .c files into build system and resolve a few of the many, many compilation/design problems.
net/mld: Add support for MLD statistics.
net/mld: Hook in MLD poll and packet transmission logic.
net/mld: Change references to IPv4 definitions to IPv6 definitions; Remove mld_input() since MLD piggybacks on ICMPv6 input. Add functions to catch MLD messages dispatched by ICMPv6 input logic.
net/mld: As a starting point, copy all net/igmp/*.c files to net/mld/. and change all occurrences of igmp (or IGMP) to mld (or MLD).
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.
chao.an