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.
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]
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
