fork() subprocesses to handle uevents in parallel.
This reduces coldboot time on bullhead from ~446ms to ~230ms.
This reduces coldboot time on sailfish from ~690ms to ~360ms.
This reduces coldboot time on ryu from ~187ms to ~122ms.
Bug: 33785894
Test: boot bullhead x40, observe no major differences in /dev and /sys
Test: boot sailfish x40, observe no major differences in /dev and /sys
Test: boot ryu x40, observe no major differences in /dev and /sys
Test: boottime tests on bullhead and sailfish
Test: init unit tests
Change-Id: Ie2f63e000b8af78d187477d31fe109f20304d749
devices.cpp handles too many things for creating one class. This
change breaks it up into various files and classes.
* Parsing is moved to ueventd_parser.cpp
* Reading from the uevent socket and Cold booting is moved to a
UeventListener class, in uevent_listener.cpp
* Firmware handling is moved to firmware_handler.cpp
* The remaining contents form a DeviceHandler class within devices.cpp
Bug: 33785894
Test: boot bullhead x40, observe no major differences in /dev and /sys
Test: boot sailfish x40, observe no major differences in /dev and /sys
Test: init unit tests
Change-Id: I846a2e5995fbb344c7a8e349065c18a934fa6aba
Tom Cherry