On Sat, Jun 15, 2024 at 03:28:14AM +0200, Peter Zijlstra wrote:

On Fri, Jun 14, 2024 at 12:48:37PM +0200, Vincent Guittot wrote:

quoted

The main problem is that need_resched becomes somewhat meaningless
because it doesn't  only mean "I need to resched a task" and we have
to add more tests around even for those not using polling

True, however we already had some of that by having the wakeup list,
that made nr_running less 'reliable'.

Doesn't using !idle_cpu() instead of need_resched() in those balance
paths already do the right thing?

Checking need_resched() as an indicator of it getting work is already a
bit an assumption.

Also, Ingo, idle_cpu() and friends don't really belong in syscalls.c...