The patch titled
Subject: mm/mmap.c: make vma_merge() comment more easy to understand
has been added to the -mm tree. Its filename is
mm-mmapc-make-vma_merge-comment-more-easy-to-understand.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-mmapc-make-vma_merge-comment-more-easy-to-understand.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-mmapc-make-vma_merge-comment-more-easy-to-understand.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Subject: mm/mmap.c: make vma_merge() comment more easy to understand
Case 1/6, 2/7 and 3/8 have the same pattern and we handle them in the
same logic.
Rearrange the comment to make it a little easy for audience to
understand.
Link: http://lkml.kernel.org/r/20191030012445.16944-1-richardw.yang@xxxxxxxxxxxxxxx
Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Cc: Steve Capper <steve.capper@xxxxxxx>
Cc: Michel Lespinasse <walken@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Yangtao Li <tiny.windzz@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mmap.c | 21 ++++++++++++---------
1 file changed, 12 insertions(+), 9 deletions(-)
--- a/mm/mmap.c~mm-mmapc-make-vma_merge-comment-more-easy-to-understand
+++ a/mm/mmap.c
@@ -1091,15 +1091,18 @@ can_vma_merge_after(struct vm_area_struc
* the area passed down from mprotect_fixup, never extending beyond one
* vma, PPPPPP is the prev vma specified, and NNNNNN the next vma after:
*
- * AAAA AAAA AAAA AAAA
- * PPPPPPNNNNNN PPPPPPNNNNNN PPPPPPNNNNNN PPPPNNNNXXXX
- * cannot merge might become might become might become
- * PPNNNNNNNNNN PPPPPPPPPPNN PPPPPPPPPPPP 6 or
- * mmap, brk or case 4 below case 5 below PPPPPPPPXXXX 7 or
- * mremap move: PPPPXXXXXXXX 8
- * AAAA
- * PPPP NNNN PPPPPPPPPPPP PPPPPPPPNNNN PPPPNNNNNNNN
- * might become case 1 below case 2 below case 3 below
+ * AAAA AAAA AAAA
+ * PPPPPPNNNNNN PPPPPPNNNNNN PPPPPPNNNNNN
+ * cannot merge might become might become
+ * PPNNNNNNNNNN PPPPPPPPPPNN
+ * mmap, brk or case 4 below case 5 below
+ * mremap move:
+ * AAAA AAAA
+ * PPPP NNNN PPPPNNNNXXXX
+ * might become might become
+ * PPPPPPPPPPPP 1 or PPPPPPPPPPPP 6 or
+ * PPPPPPPPNNNN 2 or PPPPPPPPXXXX 7 or
+ * PPPPNNNNNNNN 3 PPPPXXXXXXXX 8
*
* It is important for case 8 that the vma NNNN overlapping the
* region AAAA is never going to extended over XXXX. Instead XXXX must
_
Patches currently in -mm which might be from richardw.yang@xxxxxxxxxxxxxxx are
mm-mmapc-remove-a-never-trigger-warning-in-__vma_adjust.patch
mm-mmapc-prev-could-be-retrieved-from-vma-vm_prev.patch
mm-mmapc-__vma_unlink_prev-is-not-necessary-now.patch
mm-mmapc-extract-__vma_unlink_list-as-counter-part-for-__vma_link_list.patch
mm-mmapc-rb_parent-is-not-necessary-in-__vma_link_list.patch
mm-rmapc-dont-reuse-anon_vma-if-we-just-want-a-copy.patch
mm-rmapc-reuse-mergeable-anon_vma-as-parent-when-fork.patch
hugetlb-remove-unused-hstate-in-hugetlb_fault_mutex_hash.patch
mm-mmapc-make-vma_merge-comment-more-easy-to-understand.patch
userfaultfd-use-vma_pagesize-for-all-huge-page-size-calculation.patch
userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb.patch
userfaultfd-wrap-the-common-dst_vma-check-into-an-inlined-function.patch
mm-fix-typo-in-the-comment-when-calling-function-__setpageuptodate.patch
