This function is used to decrement the program counter to re-run a given
instruction. This can be used as a cheap way to implement blocking
calls.
Signed-off-by: Sean Cross <sean@xobs.io>
Previously, each process could return one chunk of memory. With this
change, processes can now return one chunk of memory per thread. This
enables multiple threads to lend memory to a server.
Signed-off-by: Sean <xobs@ci.betrusted.io>
Cargo appears to cache packages in the workspace when multiple packages
use the same crate. Unfortunately, Xous uses different features
depending on whether it's running in the kernel or in userspace.
Pull the kernel version of "xous" in under a different namespace in
order to force it to use a different build.
Signed-off-by: Sean Cross <sean@xobs.io>
This package serves only to build tests for the kernel, because the
kernel wants to use a different mechanism for spawning processes.
Cargo doesn't support having `#[cfg(test)]` attributes on modules in
order to allow conditional compilation depending on whether we're
running a test or not. To work around this, `main.rs` is included in
another dummy crate.
Signed-off-by: Sean Cross <sean@xobs.io>
This now uses a system of access keys to associate processes with the
kernel.
This currently does not pass tests.
Signed-off-by: Sean Cross <sean@xobs.io>
Connections weren't getting multiplexed correctly. As a result, they
would respond with the wrong message to a given thread.
Signed-off-by: Sean Cross <sean@xobs.io>
Previously, we were recycling PIDs when devices disconnected, however we
weren't cleaning up PIDs within the system-level table.
This now cleans up these entries.
Signed-off-by: Sean Cross <sean@xobs.io>
We now have two tests. These tests may be run either in parallel or in series.
If they are run in parallel, then they will each have their own thread
local storage, and each will initialize things from scratch.
If they are run in series, then the thread local storage will be reused
between the two processes.
Signed-off-by: Sean Cross <sean@xobs.io>
This gets basic scalar message passing working again. With this, the
following operations may be performed:
* Starting a server
* Connecting to a server
* Sending a scalar message
Care must be taken to not overflow a server's queue, particularly if
writers are faster than readers.
Signed-off-by: Sean Cross <sean@xobs.io>
The goal is to get a basic message passing engine working that will also
function as a device that works on real hardware.
This is still reworking it to function correctly on a desktop system.
Once that is working, it will be reworked to function once again on
hardware.
Signed-off-by: Sean Cross <sean@xobs.io>
This refactors the kernel so that it *can* run on baremetal, but it can
also run as part of a full system.
This will aid in developing, and ensure that a minimum amount of unsafe
code is present within the kernel.
Signed-off-by: Sean Cross <sean@xobs.io>
