This is meant to be an example scheduler that won't necessarily run well
in production. Let's remove the 3 second timeout and use the system
default of 30.
Signed-off-by: David Vernet <void@manifault.com>
In the latest kernel, sched_ext API has changed in two areas:
- ops.prep_enable/cancel_enable/enable/disable() replaced with
ops.init_task/enable/disable/exit_task().
- scx_bpf_dispatch() can now be called from ops.select_cpu(). Also,
SCX_ENQ_LOCAL flag is removed. Instead, users can call
scx_bpf_select_cpu_dfl() from ops.select_cpu() and use the @is_idle out
param value to determine whether to dispatch directly.
This commit updates all schedules so that they build.
- Init functions renamed / merged / split.
- ops.select_cpu() is added to several schedulers and local direct
disptching logic is moved there.
This is the minimum update which is need to make the schedulers build and
work. It needs further update to e.g. move vtime udpates to ops.enable().
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
