arch/xen/kernel/evtchn.c: Communication via Xen event channels
->HYPERVISOR_xen_version call 
->HYPERVISOR_physdev_op call
->HYPERVISOR_event_channel_op call
-> global HYPERVISOR_shared_info

arch/xen/kernel/fixup.c: binary rewrinting for threads TLS
-> message to suppress... + boot delay

arch/xen/kernel/gnttab.c: memory access and sharing
  inline assemby from privcmd.c using TRAP_INSTR macro to do an hypervisor
  call apparently.

arch/xen/kernel/reboot.c: 
-> HYPERVISOR_suspend call

include/asm-xen/asm-i386/hypercall.h:
-> assembly macro for the hypervisor calls

tools/libxc/xc_*.c: library for xen control

tools/libxc/xc_private.h:
  -> Xen hypervisor call is an ioctl() with an privcmd_hypercall_t parameter
  xc_domain.c:
  -> API for all domain supervisor calls, create, memory, cpu weight, destroy

=> Fraser all over the place ...

/Xen/xen-unstable.hg/tools/libxc


  The hypervisor calls are defined as inlined functions in xc_private.h
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