Re: [Crash-utility] [RFC] [PATCH 1/6] Port linux maple tree related files to crash

There are 2 ways to iterate vm_area_struct: 1) by rbtree, aka vma.vm_rb; 2) by linked list, aka vma.vm_prev/next. However for linux maple tree patch[1][2], vm_rb and vm_prev/next are removed from vm_area_struct. For memory.c:vm_area_dump of crash, it mainly uses linked list as a way of vma iteration, which will not work for this case. So maple tree iteration need to be ported to crash. For crash, currently it only iteratively read the maple tree, no more rcu safe or maple tree modification features needed. So we only port a subset of kernel maple tree features. This patch mainly ports for_each_vma() macro, and all its dependencies from kernel source[3] to crash, to enable crash maple tree vma iteration: maple_tree_vma.h: The interface of maple tree vma iteration. maple_tree.c: Maple tree main implementation. maple_tree.h: Maple tree constants and structures. xarray.h: Maple tree of xarray dependency.

[1]: https://github.com/oracle/linux-uek/commit/d19703645b80abe35dff1a88449d07... [2]: https://github.com/oracle/linux-uek/commit/91dee01f1ebb6b6587463b6ee6f7bb... [3]: https://github.com/oracle/linux-uek, maple/mainline branch

Signed-off-by: Tao Liu <ltao(a)redhat.com&gt; --- maple_tree.c | 736 +++++++++++++++++++++++++++++++++++++++++++++++ maple_tree.h | 176 ++++++++++++ maple_tree_vma.h | 31 ++ xarray.h | 70 +++++ 4 files changed, 1013 insertions(+) create mode 100644 maple_tree.c create mode 100644 maple_tree.h create mode 100644 maple_tree_vma.h create mode 100644 xarray.h diff --git a/maple_tree.c b/maple_tree.c new file mode 100644 index 0000000..a7db8fa --- /dev/null +++ b/maple_tree.c @@ -0,0 +1,736 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Maple Tree implementation + * Copyright (c) 2018-2022 Oracle Corporation + * Authors: Liam R. Howlett <Liam.Howlett(a)oracle.com&gt; + * Matthew Wilcox <willy(a)infradead.org&gt;