On Thu, Aug 09, 2012 at 12:22:17AM -0700, Tejun Heo wrote:

On Wed, Aug 08, 2012 at 06:39:23PM -0700, Kent Overstreet wrote:

quoted

On Wed, Aug 08, 2012 at 04:05:32PM -0700, Tejun Heo wrote:

quoted

One more thing.

On Mon, Aug 06, 2012 at 03:08:37PM -0700, Kent Overstreet wrote:

quoted

+	if (bio_integrity(bio)) {
+		bio_integrity_clone(ret, bio, gfp, bs);
+		bio_integrity_trim(ret, 0, bio_sectors(ret));
+		bio_integrity_trim(bio, bio_sectors(ret), bio_sectors(bio));

Is this equivalent to bio_integrity_split() performance-wise?

Strictly speaking, no. But it has the advantage of being drastically
simpler - and the only one only worked for single page bios so I
would've had to come up with something new from scratch, and as
confusing as the integrity stuff is I wouldn't trust the result.

There's already bio_integrity_split() and you're actively dropping it.

Because it only works for single page bios, AFAICT. I'd have to start
from scratch.

quoted

I'm skeptical that it's going to matter in practice given how much
iteration is done elsewhere in the course of processing a bio and given
that this stuff isn't used with high end SSDs...

If you think the active dropping is justified, please let the change
and justification clearly stated.  You're burying the active change in
two separate patches without even mentioning it or cc'ing people who
care about bio-integrity (Martin K. Petersen). 

Not intentionally, he isn't in MAINTAINERS so get_maintainers.pl missed
it and it slipped by while I was looking for people to CC. Added him.