Re: [PATCH 3/4] pnfs/blocklayout: allocate separate pages for the layoutcommit payload

[Christoph Hellwig <hch@lst.de>]

On Thu, Sep 11, 2014 at 10:16:56AM -0400, Anna Schumaker wrote:
> > +		arg->layoutupdate_pages =
> > +			kcalloc(DIV_ROUND_UP(buffer_size, PAGE_SIZE),
> > +				sizeof(struct page *), GFP_NOFS);
> 
> I don't think I've seen kcalloc() before.  What does it do?

The same as calloc(3) in userspace - allocate an array of nent entries
of size, and zero the result that is returned.

> >  	dprintk("%s found %i ranges\n", __func__, count);
> 
> I'm getting this:
> 
> fs/nfs/blocklayout/extent_tree.c: In function ‘ext_tree_prepare_commit’:
> fs/nfs/blocklayout/extent_tree.c:565:2: warning: format ‘%i’ expects argument of type ‘int’, but argument 3 has type ‘size_t’ [-Wformat=]
>   dprintk("%s found %i ranges\n", __func__, count);

For some reason I haven't managed to trigger this warning even after
turning on CONFIG_SUNRPC_DEBUG, but it should be easy to fix up..