mm: refactor of vma_merge()

Patch series "Refactor of vma_merge and new merge call", v4.

I am currently working on my master's thesis trying to increase number of
merges of VMAs currently failing because of page offset incompatibility
and difference in their anon_vmas.  The following refactor and added merge
call included in this series is just two smaller upgrades I created along
the way.


This patch (of 2):

Refactor vma_merge() to make it shorter and more understandable.  Main
change is the elimination of code duplicity in the case of merge next
check.  This is done by first doing checks and caching the results before
executing the merge itself.  The variable 'area' is divided into 'mid' and
'res' as previously it was used for two purposes, as the middle VMA
between prev and next and also as the result of the merge itself.  Exit
paths are also unified.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jakub Matěna <[email protected]>
Reviewed-by: Vlastimil Babka <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Liam Howlett <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: "Kirill A . Shutemov" <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions