When applying this patch and running it a typical output looks like
this:


Jun  7 00:41:10 dox kernel: shrink_mmap:     2     0     0     0  
212     0    0     0     0 

First 2 is PID
then comes the counters for different reasons to continue.

The fourth counter is 'count_noncarezone'

I interprete this as:


a) shrink_mmap hits - we need both Normal and DMA pages.
b) Normal pages are easily fulfilled.
c) DMA pages are rare among all Normal pages.
d) When a Normal page is found it is counted as tested but
  then discarded.
e) while loops ends (before finding any DMA pages)
f) shrink_mmap has failed
g) swapping starts...

What to do about it:
a) Move the zone check early - buffers may get old...
b) Undo counting before continuing due to wrong zone

I and others will examine our options.

/RogerL

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