Re: [PATCH v3 5/7] swap: Use bdev_read_page() / bdev_write_page()

[Matthew Wilcox]

On Thu, Apr 24, 2014 at 11:18:17AM -0700, Andrew Morton wrote:
> On Sun, 13 Apr 2014 18:59:54 -0400 Matthew Wilcox <matthew.r.wilcox@xxxxxxxxx> wrote:
> 
> >  mm/page_io.c | 23 +++++++++++++++++++++--
> >  1 file changed, 21 insertions(+), 2 deletions(-)
> 
> Some changelog here would be nice.  What were the reasons for the
> change?  Any observable performance changes?

Whoops ... I could swear I wrote one.  Wonder what happened to it.  Here
was all I had:

We can avoid allocating a BIO if we use the writepage path instead of
the Direct I/O path.

But that's kind of lame.  I don't have any performance numbers right now,
so how about we go with:

By calling the device driver to write the page directly, we avoid
allocating a BIO, which allows us to free memory without allocating
memory.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/