Messages in this thread |  | | | Date | Wed, 2 Jul 2008 19:35:11 -0700 (PDT) | | From | Linus Torvalds <> | | Subject | Re: [PATCH 1/2] Introduce copy_user_handle_tail routine |
On Wed, 2 Jul 2008, Vitaly Mayatskikh wrote:
>
> Linus wanted this routine to be extremely dumb.
Well, I wanted it simple and dumb, but not dumber than _necessary_.
I think
if (cleartail)
memset(dst,0,len);
return len;
is basically what we should have at the end. Simple and sweet.
Now, the stuff that comes *before* that point is the "try to fix up one
byte at a time" thing, which I'd like to be simple and dumb. At least to
start with.
Of course, I also suspect that *eventually* we might want to make it
smarter and more complex. For example, while performance isn't a primary
issue, we might want to eventually avoid having to do _two_ faults (once
in the fast unrolled or word-at-a-time loop, and once in the byte-for-byte
one), by limiting the byte-for-byte one to be within a page, but that
would be a "future enhancement" thing.
Linus
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