diff options
| -rw-r--r-- | scripts/gdb/linux/constants.py.in | 7 | ||||
| -rw-r--r-- | scripts/gdb/linux/radixtree.py | 97 | ||||
| -rw-r--r-- | scripts/gdb/vmlinux-gdb.py | 1 |
3 files changed, 105 insertions, 0 deletions
diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in index 7986f4e0da12..07e6c2befe36 100644 --- a/scripts/gdb/linux/constants.py.in +++ b/scripts/gdb/linux/constants.py.in @@ -14,6 +14,7 @@ #include <linux/fs.h> #include <linux/mount.h> +#include <linux/radix-tree.h> /* We need to stringify expanded macros so that they can be parsed */ @@ -50,3 +51,9 @@ LX_VALUE(MNT_NOEXEC) LX_VALUE(MNT_NOATIME) LX_VALUE(MNT_NODIRATIME) LX_VALUE(MNT_RELATIME) + +/* linux/radix-tree.h */ +LX_VALUE(RADIX_TREE_INDIRECT_PTR) +LX_GDBPARSED(RADIX_TREE_HEIGHT_MASK) +LX_GDBPARSED(RADIX_TREE_MAP_SHIFT) +LX_GDBPARSED(RADIX_TREE_MAP_MASK) diff --git a/scripts/gdb/linux/radixtree.py b/scripts/gdb/linux/radixtree.py new file mode 100644 index 000000000000..0fdef4e2971a --- /dev/null +++ b/scripts/gdb/linux/radixtree.py @@ -0,0 +1,97 @@ +# +# gdb helper commands and functions for Linux kernel debugging +# +# Radix Tree Parser +# +# Copyright (c) 2016 Linaro Ltd +# +# Authors: +# Kieran Bingham <kieran.bingham@linaro.org> +# +# This work is licensed under the terms of the GNU GPL version 2. +# + +import gdb + +from linux import utils +from linux import constants + +radix_tree_root_type = utils.CachedType("struct radix_tree_root") +radix_tree_node_type = utils.CachedType("struct radix_tree_node") + + +def is_indirect_ptr(node): + long_type = utils.get_long_type() + return (node.cast(long_type) & constants.LX_RADIX_TREE_INDIRECT_PTR) + + +def indirect_to_ptr(node): + long_type = utils.get_long_type() + node_type = node.type + indirect_ptr = node.cast(long_type) & ~constants.LX_RADIX_TREE_INDIRECT_PTR + return indirect_ptr.cast(node_type) + + +def maxindex(height): + height = height & constants.LX_RADIX_TREE_HEIGHT_MASK + return gdb.parse_and_eval("height_to_maxindex["+str(height)+"]") + + +def lookup(root, index): + if root.type == radix_tree_root_type.get_type().pointer(): + root = root.dereference() + elif root.type != radix_tree_root_type.get_type(): + raise gdb.GdbError("Must be struct radix_tree_root not {}" + .format(root.type)) + + node = root['rnode'] + if node is 0: + return None + + if not (is_indirect_ptr(node)): + if (index > 0): + return None + return node + + node = indirect_to_ptr(node) + + height = node['path'] & constants.LX_RADIX_TREE_HEIGHT_MASK + if (index > maxindex(height)): + return None + + shift = (height-1) * constants.LX_RADIX_TREE_MAP_SHIFT + + while True: + new_index = (index >> shift) & constants.LX_RADIX_TREE_MAP_MASK + slot = node['slots'][new_index] + + node = slot.cast(node.type.pointer()).dereference() + if node is 0: + return None + + shift -= constants.LX_RADIX_TREE_MAP_SHIFT + height -= 1 + + if (height <= 0): + break + + return node + + +class LxRadixTree(gdb.Function): + """ Lookup and return a node from a RadixTree. + +$lx_radix_tree_lookup(root_node [, index]): Return the node at the given index. +If index is omitted, the root node is dereferenced and returned.""" + + def __init__(self): + super(LxRadixTree, self).__init__("lx_radix_tree_lookup") + + def invoke(self, root, index=0): + result = lookup(root, index) + if result is None: + raise gdb.GdbError("No entry in tree at index {}".format(index)) + + return result + +LxRadixTree() diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py index 6e0b0afd888a..3a80ad6eecad 100644 --- a/scripts/gdb/vmlinux-gdb.py +++ b/scripts/gdb/vmlinux-gdb.py @@ -31,3 +31,4 @@ else: import linux.lists import linux.proc import linux.constants + import linux.radixtree |