[PATCH 0/6] scripts/gdb: Fixes for 4.7

[PATCH 0/6] scripts/gdb: Fixes for 4.7

[Kieran Bingham]

Hi Andrew,

Please consider this series for integration into the current rc series.
I had hoped to get this to you, with a fixed radix-tree, rather than a
reverted one. Alas, time has gone against me, and we are nearing the end
of the window - so having discussed with Jan, we felt it best to simply
revert the feature for this release.

Aside from the revert, we have four fairly minor fixups.

Kieran Bingham (4):
  scripts/gdb: silence 'nothing to do' message
  scripts/gdb: rebuild constants.py on dependancy change
  Revert "scripts/gdb: add a Radix Tree Parser"
  Revert "scripts/gdb: add documentation example for radix tree"

Nikolay Borisov (1):
  scripts/gdb: Perform path expansion to lx-symbol's arguments

Omar Sandoval (1):
  scripts/gdb: add constants.py to .gitignore

 Documentation/gdb-kernel-debugging.txt | 21 --------
 scripts/gdb/linux/.gitignore           |  1 +
 scripts/gdb/linux/Makefile             |  6 ++-
 scripts/gdb/linux/constants.py.in      |  7 ---
 scripts/gdb/linux/radixtree.py         | 97 ----------------------------------
 scripts/gdb/linux/symbols.py           |  2 +-
 scripts/gdb/vmlinux-gdb.py             |  1 -
 7 files changed, 6 insertions(+), 129 deletions(-)
 delete mode 100644 scripts/gdb/linux/radixtree.py

-- 
2.7.4

[PATCH 1/6] scripts/gdb: silence 'nothing to do' message

[Kieran Bingham]

The constants.py generation, involves a rule to link into the main
makefile. This rule has no command and generates a spurious warning
message in the build logs when CONFIG_SCRIPTS_GDB is enabled.

Fix simply by giving a no-op action

Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
 scripts/gdb/linux/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
index cd129e65d1ff..7a33556db4e1 100644
--- a/scripts/gdb/linux/Makefile
+++ b/scripts/gdb/linux/Makefile
@@ -17,5 +17,6 @@ $(obj)/constants.py: $(SRCTREE)/$(obj)/constants.py.in
 	$(call if_changed,gen_constants_py)
 
 build_constants_py: $(obj)/constants.py
+	@:
 
 clean-files := *.pyc *.pyo $(if $(KBUILD_SRC),*.py) $(obj)/constants.py
-- 
2.7.4

[PATCH 2/6] scripts/gdb: rebuild constants.py on dependancy change

[Kieran Bingham]

The autogenerated constants.py file was only being built on the initial
call, and if the constants.py.in file changed. As we are utilising the
CPP hooks, we can successfully use the call if_changed_dep rules to
determine when to rebuild the file based on it's inclusions.

Reported-by: Jan Kiszka <jan.kiszka@web.de>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
 scripts/gdb/linux/Makefile | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile
index 7a33556db4e1..8b00031f5349 100644
--- a/scripts/gdb/linux/Makefile
+++ b/scripts/gdb/linux/Makefile
@@ -13,8 +13,9 @@ quiet_cmd_gen_constants_py = GEN     $@
 	$(CPP) -E -x c -P $(c_flags) $< > $@ ;\
 	sed -i '1,/<!-- end-c-headers -->/d;' $@
 
-$(obj)/constants.py: $(SRCTREE)/$(obj)/constants.py.in
-	$(call if_changed,gen_constants_py)
+targets += constants.py
+$(obj)/constants.py: $(SRCTREE)/$(obj)/constants.py.in FORCE
+	$(call if_changed_dep,gen_constants_py)
 
 build_constants_py: $(obj)/constants.py
 	@:
-- 
2.7.4

[PATCH 3/6] scripts/gdb: add constants.py to .gitignore

[Kieran Bingham]

From: Omar Sandoval <osandov@fb.com>

Since scripts/gdb/linux/constants.py is autogenerated, this should have
been added to .gitignore when it was introduced.

Fixes: f197d75fcad1 ("scripts/gdb: provide linux constants")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
 scripts/gdb/linux/.gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/gdb/linux/.gitignore b/scripts/gdb/linux/.gitignore
index 52e4e61140d1..2573543842d0 100644
--- a/scripts/gdb/linux/.gitignore
+++ b/scripts/gdb/linux/.gitignore
@@ -1,2 +1,3 @@
 *.pyc
 *.pyo
+constants.py
-- 
2.7.4

[PATCH 4/6] scripts/gdb: Perform path expansion to lx-symbol's arguments

[Kieran Bingham]

From: Nikolay Borisov <n.borisov.lkml@gmail.com>

Python doesn't do automatic expansion of paths. In case one passes
path of the from ~/foo/bar the gdb scripts won't automatically expand
that and as a result the symbols files won't be loaded. Fix this
by explicitly expanding all paths which begin with "~"

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
 scripts/gdb/linux/symbols.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/gdb/linux/symbols.py b/scripts/gdb/linux/symbols.py
index 9a0f8923f67c..004b0ac7fa72 100644
--- a/scripts/gdb/linux/symbols.py
+++ b/scripts/gdb/linux/symbols.py
@@ -153,7 +153,7 @@ lx-symbols command."""
             saved_state['breakpoint'].enabled = saved_state['enabled']
 
     def invoke(self, arg, from_tty):
-        self.module_paths = arg.split()
+        self.module_paths = [os.path.expanduser(p) for p in arg.split()]
         self.module_paths.append(os.getcwd())
 
         # enforce update
-- 
2.7.4

[PATCH 5/6] Revert "scripts/gdb: add a Radix Tree Parser"

[Kieran Bingham]

This reverts commit e127a73d41ac ("scripts/gdb: add a Radix Tree Parser")

The python implementation of radix-tree was merged at the same time as
the radix-tree system was heavily reworked from commit e9256efcc8e3
("radix-tree: introduce radix_tree_empty") to 3bcadd6fa6c4 ("radix-tree:
free up the bottom bit of exceptional entries for reuse") and no longer
functions, but also prevents other gdb scripts from loading.

This functionality has not yet hit a release, so simply remove it for
now

Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
Due to unfortunate timing, the radix tree python implementation was
merged at the same time as the radix-tree itself was heavily rewritten.
Unfortunately I have not been able to find enough time to rewrite the
python implementation in this rc-window, and as the radix-tree.py has
not yet made it out to a release in a working state, at this point the
best thing to do is to revert it. (It currently causes breakage for the
other gdb scripts

I will then intend to resubmit a new implementation for a later release,
and also we can plan an automated test service for the scripts to catch
these issues earlier.

 scripts/gdb/linux/constants.py.in |  7 ---
 scripts/gdb/linux/radixtree.py    | 97 ---------------------------------------
 scripts/gdb/vmlinux-gdb.py        |  1 -
 3 files changed, 105 deletions(-)
 delete mode 100644 scripts/gdb/linux/radixtree.py

diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
index 07e6c2befe36..7986f4e0da12 100644
--- a/scripts/gdb/linux/constants.py.in
+++ b/scripts/gdb/linux/constants.py.in
@@ -14,7 +14,6 @@
 
 #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 */
 
@@ -51,9 +50,3 @@ 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
deleted file mode 100644
index 0fdef4e2971a..000000000000
--- a/scripts/gdb/linux/radixtree.py
+++ /dev/null
@@ -1,97 +0,0 @@
-#
-# 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 3a80ad6eecad..6e0b0afd888a 100644
--- a/scripts/gdb/vmlinux-gdb.py
+++ b/scripts/gdb/vmlinux-gdb.py
@@ -31,4 +31,3 @@ else:
     import linux.lists
     import linux.proc
     import linux.constants
-    import linux.radixtree
-- 
2.7.4

[PATCH 6/6] Revert "scripts/gdb: add documentation example for radix tree"

[Kieran Bingham]

This reverts commit 9b5580359a84 ("scripts/gdb: add documentation
example for radix tree")

The python implementation of radix tree was merged at the same time as a
refactoring of the radix tree implementation and doesn't work. The
feature is being reverted, thus we revert the documentation as well.

Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
---
 Documentation/gdb-kernel-debugging.txt | 21 ---------------------
 1 file changed, 21 deletions(-)

diff --git a/Documentation/gdb-kernel-debugging.txt b/Documentation/gdb-kernel-debugging.txt
index 4ab7d43d0754..7050ce8794b9 100644
--- a/Documentation/gdb-kernel-debugging.txt
+++ b/Documentation/gdb-kernel-debugging.txt
@@ -139,27 +139,6 @@ Examples of using the Linux-provided gdb helpers
       start_comm = "swapper/2\000\000\000\000\000\000"
     }
 
- o Dig into a radix tree data structure, such as the IRQ descriptors:
-    (gdb) print (struct irq_desc)$lx_radix_tree_lookup(irq_desc_tree, 18)
-    $6 = {
-      irq_common_data = {
-        state_use_accessors = 67584,
-        handler_data = 0x0 <__vectors_start>,
-        msi_desc = 0x0 <__vectors_start>,
-        affinity = {{
-            bits = {65535}
-          }}
-      },
-      irq_data = {
-        mask = 0,
-        irq = 18,
-        hwirq = 27,
-        common = 0xee803d80,
-        chip = 0xc0eb0854 <gic_data>,
-        domain = 0xee808000,
-        parent_data = 0x0 <__vectors_start>,
-        chip_data = 0xc0eb0854 <gic_data>
-      } <... trimmed ...>
 
 List of commands and functions
 ------------------------------
-- 
2.7.4

Re: [PATCH 0/6] scripts/gdb: Fixes for 4.7

[Jan Kiszka]

On 2016-06-28 17:22, Kieran Bingham wrote:
> Hi Andrew,
> 
> Please consider this series for integration into the current rc series.
> I had hoped to get this to you, with a fixed radix-tree, rather than a
> reverted one. Alas, time has gone against me, and we are nearing the end
> of the window - so having discussed with Jan, we felt it best to simply
> revert the feature for this release.
> 
> Aside from the revert, we have four fairly minor fixups.
> 
> Kieran Bingham (4):
>   scripts/gdb: silence 'nothing to do' message
>   scripts/gdb: rebuild constants.py on dependancy change
>   Revert "scripts/gdb: add a Radix Tree Parser"
>   Revert "scripts/gdb: add documentation example for radix tree"
> 
> Nikolay Borisov (1):
>   scripts/gdb: Perform path expansion to lx-symbol's arguments
> 
> Omar Sandoval (1):
>   scripts/gdb: add constants.py to .gitignore
> 
>  Documentation/gdb-kernel-debugging.txt | 21 --------
>  scripts/gdb/linux/.gitignore           |  1 +
>  scripts/gdb/linux/Makefile             |  6 ++-
>  scripts/gdb/linux/constants.py.in      |  7 ---
>  scripts/gdb/linux/radixtree.py         | 97 ----------------------------------
>  scripts/gdb/linux/symbols.py           |  2 +-
>  scripts/gdb/vmlinux-gdb.py             |  1 -
>  7 files changed, 6 insertions(+), 129 deletions(-)
>  delete mode 100644 scripts/gdb/linux/radixtree.py
> 

For all:
Acked-by: Jan Kiszka <jan.kiszka@siemens.com>

Thanks!
Jan

-- 
Siemens AG, Corporate Technology, CT RDA ITP SES-DE
Corporate Competence Center Embedded Linux

Re: [PATCH 0/6] scripts/gdb: Fixes for 4.7

[Kieran Bingham]

Hi Andrew,

Will this fixes series be able to make it for 4.7 ?

--
Regards

Kieran

On 29/06/16 06:00, Jan Kiszka wrote:
> On 2016-06-28 17:22, Kieran Bingham wrote:
>> Hi Andrew,
>>
>> Please consider this series for integration into the current rc series.
>> I had hoped to get this to you, with a fixed radix-tree, rather than a
>> reverted one. Alas, time has gone against me, and we are nearing the end
>> of the window - so having discussed with Jan, we felt it best to simply
>> revert the feature for this release.
>>
>> Aside from the revert, we have four fairly minor fixups.
>>
>> Kieran Bingham (4):
>>   scripts/gdb: silence 'nothing to do' message
>>   scripts/gdb: rebuild constants.py on dependancy change
>>   Revert "scripts/gdb: add a Radix Tree Parser"
>>   Revert "scripts/gdb: add documentation example for radix tree"
>>
>> Nikolay Borisov (1):
>>   scripts/gdb: Perform path expansion to lx-symbol's arguments
>>
>> Omar Sandoval (1):
>>   scripts/gdb: add constants.py to .gitignore
>>
>>  Documentation/gdb-kernel-debugging.txt | 21 --------
>>  scripts/gdb/linux/.gitignore           |  1 +
>>  scripts/gdb/linux/Makefile             |  6 ++-
>>  scripts/gdb/linux/constants.py.in      |  7 ---
>>  scripts/gdb/linux/radixtree.py         | 97 ----------------------------------
>>  scripts/gdb/linux/symbols.py           |  2 +-
>>  scripts/gdb/vmlinux-gdb.py             |  1 -
>>  7 files changed, 6 insertions(+), 129 deletions(-)
>>  delete mode 100644 scripts/gdb/linux/radixtree.py
>>
> 
> For all:
> Acked-by: Jan Kiszka <jan.kiszka@siemens.com>
> 
> Thanks!
> Jan
> 

-- 
Regards

Kieran Bingham

Re: [PATCH 0/6] scripts/gdb: Fixes for 4.7

[Andrew Morton]

On Mon, 11 Jul 2016 11:17:21 +0100 Kieran Bingham <kieran@ksquared.org.uk> wrote:

> Will this fixes series be able to make it for 4.7 ?

Yup, I'll send them in this week.  Sorry, I've been a bit laggy the
past two weeks.  Back up to speed now though.

Re: [PATCH 0/6] scripts/gdb: Fixes for 4.7

[Kieran Bingham]

On 11/07/16 20:53, Andrew Morton wrote:
> On Mon, 11 Jul 2016 11:17:21 +0100 Kieran Bingham <kieran@ksquared.org.uk> wrote:
> 
>> Will this fixes series be able to make it for 4.7 ?
> 
> Yup, I'll send them in this week.  Sorry, I've been a bit laggy the
> past two weeks.  Back up to speed now though.

No Worries, I saw you'd only sent about 2 emails in the last two weeks
and thought you might have been on holiday.

Then I saw Linus' rc notes, and saw we get an extra week as well!

Thanks
-- 
Regards

Kieran Bingham