Sorry for the formatting. On Fri, 15 Feb 2019, 18:30 Andrii Anisov, <andrii.ani...@gmail.com> wrote:
> Hello Julien, > > On 15.02.19 18:31, Julien Grall wrote: > > Why? Is it because you want to be cache-aligned? If so, requiring the > > structure to be 64-bytes is not enough. > > I did not mean caches. > What is the reason then? > You also want the address to > > be 64-bytes aligned. > > I would keep it as a hint for static/dynamic allocations in VMs, hoping > the address would be normally 64 bytes aligned. > I hope it might be stronger than, only commenting it should not cross a > page boundary. E.g. like `struct vcpu_register_vcpu_info` is commented. > > I've got this idea after looking at runstate definition as per-cpu in > Linux [1] > It is not obvious why it would be 64-bytes alignment from the definition. Can you please explain the rationale to impose that alignment? I really appreciate you suggest ideas/patches but it would be helpful if you provide rationale at the same time. This would avoid a round of e-mails just for asking the reasons and delay the interesting bits. > > If an OS cares about it, then it can aligned itself here. > I suppose we can hint the OS by structure alignment in the interface > header, and require it from OS verifying it on hypercall handling . > [1] > https://elixir.bootlin.com/linux/v5.0-rc6/source/drivers/xen/time.c#L22 > > -- > Sincerely, > Andrii Anisov. >
_______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
