threadctxhooks-r0drv-linux.c: Looks like 3.19 stopped restoring kernel RFLAGS during context switches, so we need to handle RFLAGS.AC our selves.

threadctxhooks-r0drv-linux.c: Be a little bit more careful with EFLAGS in the context hook callouts.

another place where we have to handle SMAP

Runtime/r0drv: be on the safe side

Runtime/r0drv: Depend only on kernel config define rather than the version.

r0drv/linux/threadctxhooks: Assert may fail, don't assert here.

Runtime/r0drv/threadctxhooks: Added an assertion.

Runtime/threadctxhooks/linux: Again, Assert not AssertPtr for bools.

Runtime/threadctxhooks/linux: Assert() not AssertPtr() for booleans.

Runtime/threadctxhooks: RTThreadCtxHooksAreRegistered().

r0drv/linux: Unintentional commit of release logging.

iprt/thread.h: Define/document the return values more explicitly when NIL_RTHREADCTX handles are involved.

Runtime/r0drv: Reference counting for kernel thread-context hooks.

Runtime/r0drv/threadctxhooks: Assert on Linux that the hook invocation means it has been registered.

IPRT: Kernel thread-context hooks, Solaris implementation.

IPRT: Kernel thread-context hooks, linux implementation. Extended tstR0ThreadPreemption testcase to test the thread-context hooks.