C SCX_OPS_ATTACH() and rust scx_ops_attach() macros were not calling
.attach() and were only attaching the struct_ops. This meant that all
non-struct_ops BPF programs contained in the skels were never attached which
breaks e.g. scx_layered.
Let's fix it by adding .attach() invocation the the attach macros.
Let's make it clear that this scheduler isn't expected to perform well,
and instead point people to scx_rustland.
Signed-off-by: David Vernet <void@manifault.com>
We can sometimes hit scenarios in the scx_userland scheduler where there
is work to be done in user space, but we incorrectly fail to run the
user space scheduler. In order to avoid this, we can use global
variables that are set from both BPF and user space. The BPF-side
variable reflects when one or more tasks have been enqueued, and the
user space-side variable reflects when user space has received tasks but
has not yet dispatched them.
In the ops.update_idle() callback, we can check these variables and send
a resched IPI to a core to ensure that the user-space scheduler is
always scheduled when there's work to be done.
Signed-off-by: David Vernet <void@manifault.com>
- combine c and kernel-examples as it's confusing to have both
- rename 'rust-user' and 'c-user' to just 'rust' and 'c', which is simpler
- update and fix sync-to-kernel.sh
