Implement a ballooning mechanism in L4Linux similar to solutions like XEN's
balloon driver. Therefore the new parent interface extensions for requesting
and yielding resources are used. L4Linux registers a yield signal context at
its parent. Whenever the parent triggers a yield, the balloon driver blows up,
which means it requests all pages available, and then frees the corresponding
backend memory.
This commit comprises the following changes to enable L4Linux to use several
CPUs:
* change default configuration for x86 and ARM
* add atomic cmpxchg operation to l4re library
* implement l4_sleep (per thread)
* enable setting affinity for VCPUs and IRQs
* move "per CPU" section within linker-script (x86 only)
* introduce SMP run-script for pandaboard
* deactivate direct scheduler (Fiasco.OC syscall) access by L4Linux
Make calls using IPCs IRQ safe, handle packet exhaustion, removed
'Packet_pool', tweak TCP rmem and wmem buffer sizes to show better performance
results, use 'Net::Packet_allocator, fix 'update-patch' Makefile command
