Re: [PATCH] net: thunderx: rework mac addresses list to u64 array

From: Christoph Hellwig
Date: Thu Apr 05 2018 - 12:15:45 EST


On Thu, Apr 05, 2018 at 09:07:49AM -0700, Vadim Lomovtsev wrote:
> >
> > > + mc_list = kmalloc(sizeof(*mc_list) +
> > > + sizeof(u64) * netdev_mc_count(netdev),
> > > + GFP_ATOMIC);
> >
> > kmalloc_array(), please.
>
> In this case it would require two memory allocation calls to kmalloc() for
> xcast_addr_list struct and to kmalloc_array() for 'mc' addresses, becasue of
> different data types and so two null-ptr checks .. this is what I'd like get rid off.
>
> My idea of this was to keep number of array elements and themselves within the
> same memory block/page to reduce number of memory allocation requests, number
> of allocated pages/blocks and avoid possible memory fragmentation (however, I believe
> the latter is already handled at the mm layer).

Indeed, lets keep it as-is.