kernel_optimize_test/scripts/gdb/linux/rbtree.py
Aymeric Agon-Rambosson 50e36be1fb scripts/gdb: repair rb_first() and rb_last()
The current implementations of the rb_first() and rb_last() gdb
functions have a variable that references itself in its instanciation,
which causes the function to throw an error if a specific condition on
the argument is met.  The original author rather intended to reference
the argument and made a typo.  Referring the argument instead makes the
function work as intended.

Signed-off-by: Aymeric Agon-Rambosson <aymeric.agon@yandex.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Nikolay Borisov <n.borisov.lkml@gmail.com>
Cc: Jackie Liu <liuyun01@kylinos.cn>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/r/20200427051029.354840-1-aymeric.agon@yandex.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-07 19:27:20 -07:00

178 lines
4.2 KiB
Python

# SPDX-License-Identifier: GPL-2.0
#
# Copyright 2019 Google LLC.
import gdb
from linux import utils
rb_root_type = utils.CachedType("struct rb_root")
rb_node_type = utils.CachedType("struct rb_node")
def rb_first(root):
if root.type == rb_root_type.get_type():
node = root.address.cast(rb_root_type.get_type().pointer())
elif root.type != rb_root_type.get_type().pointer():
raise gdb.GdbError("Must be struct rb_root not {}".format(root.type))
node = root['rb_node']
if node is 0:
return None
while node['rb_left']:
node = node['rb_left']
return node
def rb_last(root):
if root.type == rb_root_type.get_type():
node = root.address.cast(rb_root_type.get_type().pointer())
elif root.type != rb_root_type.get_type().pointer():
raise gdb.GdbError("Must be struct rb_root not {}".format(root.type))
node = root['rb_node']
if node is 0:
return None
while node['rb_right']:
node = node['rb_right']
return node
def rb_parent(node):
parent = gdb.Value(node['__rb_parent_color'] & ~3)
return parent.cast(rb_node_type.get_type().pointer())
def rb_empty_node(node):
return node['__rb_parent_color'] == node.address
def rb_next(node):
if node.type == rb_node_type.get_type():
node = node.address.cast(rb_node_type.get_type().pointer())
elif node.type != rb_node_type.get_type().pointer():
raise gdb.GdbError("Must be struct rb_node not {}".format(node.type))
if rb_empty_node(node):
return None
if node['rb_right']:
node = node['rb_right']
while node['rb_left']:
node = node['rb_left']
return node
parent = rb_parent(node)
while parent and node == parent['rb_right']:
node = parent
parent = rb_parent(node)
return parent
def rb_prev(node):
if node.type == rb_node_type.get_type():
node = node.address.cast(rb_node_type.get_type().pointer())
elif node.type != rb_node_type.get_type().pointer():
raise gdb.GdbError("Must be struct rb_node not {}".format(node.type))
if rb_empty_node(node):
return None
if node['rb_left']:
node = node['rb_left']
while node['rb_right']:
node = node['rb_right']
return node.dereference()
parent = rb_parent(node)
while parent and node == parent['rb_left'].dereference():
node = parent
parent = rb_parent(node)
return parent
class LxRbFirst(gdb.Function):
"""Lookup and return a node from an RBTree
$lx_rb_first(root): Return the node at the given index.
If index is omitted, the root node is dereferenced and returned."""
def __init__(self):
super(LxRbFirst, self).__init__("lx_rb_first")
def invoke(self, root):
result = rb_first(root)
if result is None:
raise gdb.GdbError("No entry in tree")
return result
LxRbFirst()
class LxRbLast(gdb.Function):
"""Lookup and return a node from an RBTree.
$lx_rb_last(root): Return the node at the given index.
If index is omitted, the root node is dereferenced and returned."""
def __init__(self):
super(LxRbLast, self).__init__("lx_rb_last")
def invoke(self, root):
result = rb_last(root)
if result is None:
raise gdb.GdbError("No entry in tree")
return result
LxRbLast()
class LxRbNext(gdb.Function):
"""Lookup and return a node from an RBTree.
$lx_rb_next(node): Return the node at the given index.
If index is omitted, the root node is dereferenced and returned."""
def __init__(self):
super(LxRbNext, self).__init__("lx_rb_next")
def invoke(self, node):
result = rb_next(node)
if result is None:
raise gdb.GdbError("No entry in tree")
return result
LxRbNext()
class LxRbPrev(gdb.Function):
"""Lookup and return a node from an RBTree.
$lx_rb_prev(node): Return the node at the given index.
If index is omitted, the root node is dereferenced and returned."""
def __init__(self):
super(LxRbPrev, self).__init__("lx_rb_prev")
def invoke(self, node):
result = rb_prev(node)
if result is None:
raise gdb.GdbError("No entry in tree")
return result
LxRbPrev()