[PATCH 0/3] composite backfill optimizations

[Adam Jackson]

Resend of a patch series from back in May.  This version includes better
comments, and accounts for the punch-through behaviour of bg=None windows
when an entire stack is mapped at once.

Lightly tested on Intel GM45 with gnome-shell.

 compalloc.c |   42 ++++++++++++++++++++++++++++++++++--------
 1 file changed, 34 insertions(+), 8 deletions(-)

- ajax