Re: [PATCH 1/1] nvme-pci: Add CPU latency pm-qos handling

Christoph Hellwig
2024-10-09T08:00:55Z

On Wed, Oct 09, 2024 at 09:45:07AM +0300, Tero Kristo wrote:
> Initially, I posted the patch against block layer, but there the
> recommendation was to move this closer to the HW; i.e. NVMe driver
> level.

Even if it is called from NVMe, at lot of the code is not nvme specific.
Some of it appears block specific and other pats are entirely generic.

But I still don't see how walking cpumasks and updating paramters in
far away (in terms of cache lines and pointer dereferences) for every
single I/O could work without having a huge performance impact.