Re: [PATCH v3 2/3] sched_ext: Provide scx_bpf_task_acquire_remote_curr()
From: Tejun Heo
Date: Mon Aug 11 2025 - 13:08:37 EST
On Sat, Aug 09, 2025 at 09:01:18AM -1000, Tejun Heo wrote:
> On Tue, Aug 05, 2025 at 12:10:35PM +0100, Christian Loehle wrote:
> > Provide scx_bpf_task_acquire_remote_curr() as a way for scx schedulers
> > to check the curr task of a remote rq without assuming its lock is
> > held.
> >
> > Many scx schedulers make use of scx_bpf_cpu_rq() to check a remote curr
> > (e.g. to see if it should be preempted). This is problematic because
> > scx_bpf_cpu_rq() provides access to all fields of struct rq, most of
> > which aren't safe to use without holding the associated rq lock.
> >
> > Signed-off-by: Christian Loehle <christian.loehle@xxxxxxx>
>
> Applied 1-2 to sched_ext/for-6.17-fixes.
Reverted due to compatibility issues. Let's try again with warnings as
discussed in the other subthread.
Thanks.
--
tejun