[RESEND [PATCH] 0/2] mm/mmap.c: reduce subtree gap propagation a little

From: Wei Yang
Date: Wed Aug 28 2019 - 02:07:17 EST


When insert and delete a vma, it will compute and propagate related subtree
gap. After some investigation, we can reduce subtree gap propagation a little.

[1]: This one reduce the propagation by update *next* gap after itself, since
*next* must be a parent in this case.
[2]: This one achieve this by unlinking vma from list.

After applying these two patches, test shows it reduce 0.3% function call for
vma_compute_subtree_gap.

BTW, this series is based on some un-merged cleanup patched.

---
This version is rebased on current linus tree, whose last commit is
commit 9e8312f5e160 ("Merge tag 'nfs-for-5.3-3' of
git://git.linux-nfs.org/projects/trondmy/linux-nfs").

Wei Yang (2):
mm/mmap.c: update *next* gap after itself
mm/mmap.c: unlink vma before rb_erase

mm/mmap.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

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2.17.1