On Mon, Mar 22, 2021 at 01:57:48PM -0400, Chris Hyser wrote: > On 3/20/21 11:46 AM, Peter Zijlstra wrote: > > On Fri, Mar 19, 2021 at 04:32:49PM -0400, Joel Fernandes (Google) wrote: > > > From: Josh Don <josh...@google.com> > > > > > > Adds per-task and per-cgroup interfaces for specifying which tasks can > > > co-execute on adjacent SMT hyperthreads via core scheduling. > > > > > > The per-task interface hooks are implemented here, but are not currently > > > used. The following patch adds a prctl interface which then takes > > > advantage of these. > > > > > > The cgroup interface can be used to toggle a unique cookie value for all > > > descendent tasks, preventing these tasks from sharing with any others. > > > See Documentation/admin-guide/hw-vuln/core-scheduling.rst for a full > > > rundown. > > > > > > One important property of this interface is that neither the per-task > > > nor the per-cgroup setting overrides the other. For example, if two > > > tasks are in different cgroups, and one or both of the cgroups is tagged > > > using the per-cgroup interface, then these tasks cannot share, even if > > > they use the per-task interface to attempt to share with one another. > > > > > > The above is implemented by making the overall core scheduling cookie a > > > compound structure, containing both a task-level cookie and a > > > group-level cookie. Two tasks will only be allowed to share if all > > > fields of their respective cookies match. > > > > > > Core scheduler has extra overhead. Enable it only for machines with > > > more than one SMT hardware thread. > > > > Oh man.. I'd soooo hoped to first see the simple task interface and then > > see the cgroup patch on top of that... I'll see if I can flip them > > myself (on monday). > > Peter, given we need to rebase this and we have some cleanup, we can go > ahead and flip the order if you have not yet done so yet.
I didn't get around to it yet :/ So yes, please! Also can you then split the selftest thingies?
