]> www.infradead.org Git - users/jedix/linux-maple.git/commit
kernel/fork: use maple tree for dup_mmap() during forking
authorLiam R. Howlett <Liam.Howlett@Oracle.com>
Tue, 21 Jun 2022 20:46:55 +0000 (20:46 +0000)
committerLiam R. Howlett <Liam.Howlett@oracle.com>
Wed, 20 Jul 2022 00:01:57 +0000 (20:01 -0400)
commitb5c31e30d705235802262308a51d74d5e81af982
treea9400faab55ce16940766a79c836f6d6256e03da
parentb65e69375e015e3e0dc8be7dffc7c102c9356a24
kernel/fork: use maple tree for dup_mmap() during forking

The maple tree was already tracking VMAs in this function by an earlier
commit, but the rbtree iterator was being used to iterate the list.
Change the iterator to use a maple tree native iterator and switch to the
maple tree advanced API to avoid multiple walks of the tree during insert
operations.  Unexport the now-unused vma_store() function.

For performance reasons we bulk allocate the maple tree nodes.  The node
calculations are done internally to the tree and use the VMA count and
assume the worst-case node requirements.  The VM_DONT_COPY flag does not
allow for the most efficient copy method of the tree and so a bulk loading
algorithm is used.

Link: https://lkml.kernel.org/r/20220504010716.661115-16-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20220621204632.3370049-15-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
include/linux/mm.h
kernel/fork.c