Use a bit allocator for the allocation management of thread contexts,
instead of holding allocation information within the Thread_base objects,
which lead to race conditions in the past.
Moreover, extend the Thread_base class interface with the ability to
to add additional stacks to a thread, and associate the context they're
located in with the corresponding Thread_base object. Additional stacks
can be used to do user-level scheduling with stack switching, without breaking
Genode's API.
Fixes#1024Fixes#1036
If an RM client gets dissolved the RM server tries to first
dissolve and then destruct the according pager object. As pager objects
previously cancelled unresolved faults only in destructor the dissolve
operation blocked forever when an unresolved fault existed.
As every pager object should get dissolved before it gets destructed
(signal-context complains otherwise) no more unresolved-fault cancelling
is needed in the destructor.
ref #989
As synchronization of signal contexts is now the users business instead of
cores and the signal framework ensures that every context of a receiver gets
synchronously destructed before the destruction of the receiver itself
synchronization and thus blocking at the destruction of a kernel
receiver-object isn't necessary anymore.
ref #989
Kernel::signal_context_kill can be used by any program to halt the processing
of a signal context synchronously to prevent broken refs when core destructs
the according kernel object. In turn, Kernel::bin_signal_context doesn't block
anymore and destructs a signal context no matter if there are unacknowledged
signals. This way, cores entrypoint doesn't depend on signal acks of a
untrustworthy client anymore.
ref #989
In the future bin_* means the direct destruction of a kernel object
without any blocking. kill_* in contrast is used for bringing a
kernel object such as signal contexts synchronized into a sleeping
state from where they can be destructed without the risk of getting
broken refs in userland.
ref #989
To remap its UTCB to its context area later, a main thread needs
to know the according dataspace capability. This is done through
the start-info it receives from its creator at startup.
ref #989
The previously used RAM 0x0..0x10000000 was just an alias for
0x70000000..0x80000000. Qemu provides up to of 768 MB RAM with the
correct -m argument. This RAM is located at 0x70000000..0x90000000 and
0x20000000..0x30000000. At least the noux_tool_chain scripts are
happy to have that much RAM.
ref #964
When using the initial SP of a main thread for the UTCB
startup-argument, fork_trampoline in libc_noux gets broken.
The function expects the SP to be initialized already in contrast
to the _start function in crt0.s that is called for processes that
are not forked. As the main-thread UTCB is located at the same virtual
address for every PD anyways, we can circumvent this problem by
defining it statically.
ref #964
Struct Msg was introduced due to the handling of pagefaults
and interrupts via synchronous IPC. Its only purpose was to provide
the message type in front of the typed message. Now pagefaults and
interrupts are handled via signals and struct Msg is not necessary
anymore.
ref #958
In programs with dynamic linker, _main and thus also platform_main_bootstrap
are called twice. By now, platform_main_bootstrap tried to always access the
startup message in the UTCB of the main thread that gets overridden till the
second call.
fix#967
When saving/resuming translation table base registers, and data fault register
a VMM is able to translate the VM's virtual addresses, and to analyse aborts
it has generated.
Every thread receives a startup message from its creator through the initial
state of its userland thread-context. The thread-startup code remembers the
kernel name of the new thread by reading this message before the userland
thread-context gets polluted. This way, Kernel::current_thread_id becomes
unnecessary.
fix#953
Don't set priority and label in platform thread and then communicate this
core object via Kernel::new_thread but communicate priority and label directly.
This way kernel doesn't need to know anymore what a platform thread is.
ref #953
Instead of writing initial thread context to the platform-thread members
and then communicating this core object to kernel, core calls
Kernel::access_thread_regs first to initialize thread context and then
Kernel::start_thread without a platform-thread pointer. This way
the frontend as well as the backend of Kernel::start_thread loose
complexity and it is a first step to remove platform thread from the
vocabulary of the kernel.
ref #953
