Commit add458fe authored May 17, 2017 by Dennis Kempin

Surface: Do not copy back if front and back buffer are identical

It is unnecessary to copy from and to the same surface. Skipping
the copy back is a huge performance improvement when using shared
buffer mode and locking a rectangle of the surface.

Bug: 38398135
Test: Use stylus demo and remove full-surface locking hack.
Change-Id: Ie8d03468507489247ba4a4be5f0cde5960e69c16

parent 74cb3b6d

libs/gui/Surface.cpp

+3 −0

Original line number	Diff line number	Diff line
		@@ -1518,6 +1518,9 @@ static status_t copyBlt(
		const Region& reg,
		int *dstFenceFd)
		{
		if (dst->getId() == src->getId())
		return OK;

		// src and dst with, height and format must be identical. no verification
		// is done here.
		status_t err;