On 17/06/21 07:56, Greg KH wrote:
On Thu, Jun 17, 2021 at 04:41:44AM +0000, Jing Zhang wrote:
+ struct kvm_stats_desc {
+ __u32 flags;
+ __s16 exponent;
+ __u16 size;
+ __u32 offset;
+ __u32 unused;
+ char name[0];
+ };
<snip>
+The ``unused`` fields are reserved for future support for other types of
+statistics data, like log/linear histogram.
you HAVE to set unused to 0 for now, otherwise userspace does not know
it is unused, right?
Jing, I think you planned to use it with other flags that are unused for
now? But please do check that it's zero in the testcase.
It is not a pointer, it is the data itself.
+string starts at the end of ``struct kvm_stats_desc``.
+The maximum length (including trailing '\0') is indicated by ``name_size``
+in ``struct kvm_stats_header``.
I thought we were replacing [0] arrays with [], are you sure you should
be declaring this as [0]? Same for all structures in this document (and
code).
In C code [0] is a bit more flexible than []. I think in this
particular case [] won't work due to how the structures are declared.
In the documentation [] is certainly clearer.
Paolo
