Commit 81055e58 authored by Al Viro's avatar Al Viro
Browse files

optimize copy_page_{to,from}_iter() 



if we'd ended up in the end of a segment, jump to the
beginning of the next one (iov_offset = 0, iov++),
rather than having the next primitive deal with that.

Ought to be folded back...

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 6abd2322

mm/iov_iter.c

+8 −0
Original line number Diff line number Diff line
@@ -74,6 +74,10 @@ size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, 
	}

	kunmap(page);

done:

	if (skip == iov->iov_len) {

		iov++;

		skip = 0;

	}

	i->count -= wanted - bytes;

	i->nr_segs -= iov - i->iov;

	i->iov = iov;
@@ -152,6 +156,10 @@ size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes, 
	}

	kunmap(page);

done:

	if (skip == iov->iov_len) {

		iov++;

		skip = 0;

	}

	i->count -= wanted - bytes;

	i->nr_segs -= iov - i->iov;

	i->iov = iov;