On Thu, Jun 28, 2018 at 10:26 AM Willem de Bruijn
<willemdebruijn.ker...@gmail.com> wrote:
>
> On Wed, Jun 27, 2018 at 6:08 PM Jesus Sanchez-Palencia
> <jesus.sanchez-palen...@intel.com> wrote:
> >
> > From: Richard Cochran <rcoch...@linutronix.de>
> >
> > This patch introduces SO_TXTIME. User space enables this option in
> > order to pass a desired future transmit time in a CMSG when calling
> > sendmsg(2). The argument to this socket option is a 6-bytes long struct
> > defined as:
> >
> > struct sock_txtime {
> > clockid_t clockid;
> > u16 flags;
> > };
>
> clockid_t is __kernel_clockid_t is int is a variable length field.
> Please use fixed length fields.
Sorry, int is fine, of course, and clockid_t is used between userspace and
kernel already.
> Also, as MAX_CLOCKS is 16, only 4 bits are needed. A single u16
> is probably sufficient as cmsg argument. To future proof, a u32 will
> allow for more
> than 4 flags. But in struct sock, 16 bits should be sufficient to
> encode both clock id
> and flags.
