From 0c22fde8b0e674a201f277688f1b3a38f6e09ada Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 23 May 2016 16:24:37 -0700 Subject: scripts/gdb: Adjust module reference counter reported by lx-lsmod This takes the MODULE_REF_BASE into account. Link: http://lkml.kernel.org/r/d926d2d54caa034adb964b52215090cbdb875249.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/modules.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/modules.py b/scripts/gdb/linux/modules.py index 0a35d6dbfb80..38f5d17044c5 100644 --- a/scripts/gdb/linux/modules.py +++ b/scripts/gdb/linux/modules.py @@ -78,7 +78,7 @@ class LxLsmod(gdb.Command): address=str(layout['base']).split()[0], name=module['name'].string(), size=str(layout['size']), - ref=str(module['refcnt']['counter']))) + ref=str(module['refcnt']['counter'] - 1))) source_list = module['source_list'] t = self._module_use_type.get_type().pointer() -- cgit From f197d75fcad125f41cc6e2fdf1b3ea733db995f1 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:40 -0700 Subject: scripts/gdb: provide linux constants Some macro's and defines are needed when parsing memory, and without compiling the kernel as -g3 they are not available in the debug-symbols. We use the pre-processor here to extract constants to a dedicated module for the linux debugger extensions Top level Kbuild is used to call in and generate the constants file, while maintaining dependencies on autogenerated files in include/generated Link: http://lkml.kernel.org/r/bc3df9c25f57ea72177c066a51a446fc19e2c27f.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/Makefile | 12 +++++++++++- scripts/gdb/linux/constants.py.in | 32 ++++++++++++++++++++++++++++++++ scripts/gdb/vmlinux-gdb.py | 1 + 3 files changed, 44 insertions(+), 1 deletion(-) create mode 100644 scripts/gdb/linux/constants.py.in (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/Makefile b/scripts/gdb/linux/Makefile index 6cf1ecf61057..cd129e65d1ff 100644 --- a/scripts/gdb/linux/Makefile +++ b/scripts/gdb/linux/Makefile @@ -8,4 +8,14 @@ ifneq ($(KBUILD_SRC),) endif @: -clean-files := *.pyc *.pyo $(if $(KBUILD_SRC),*.py) +quiet_cmd_gen_constants_py = GEN $@ + cmd_gen_constants_py = \ + $(CPP) -E -x c -P $(c_flags) $< > $@ ;\ + sed -i '1,//d;' $@ + +$(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 diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in new file mode 100644 index 000000000000..79d9d0092452 --- /dev/null +++ b/scripts/gdb/linux/constants.py.in @@ -0,0 +1,32 @@ +/* + * gdb helper commands and functions for Linux kernel debugging + * + * Kernel constants derived from include files. + * + * Copyright (c) 2016 Linaro Ltd + * + * Authors: + * Kieran Bingham + * + * This work is licensed under the terms of the GNU GPL version 2. + * + */ + +/* We need to stringify expanded macros so that they can be parsed */ +#define STRING(x) #x +#define XSTRING(x) STRING(x) + +#define LX_VALUE(x) LX_##x = x +#define LX_GDBPARSED(x) LX_##x = gdb.parse_and_eval(XSTRING(x)) + +/* + * IS_ENABLED generates (a || b) which is not compatible with python + * We can only switch on configuration items we know are available + * Therefore - IS_BUILTIN() is more appropriate + */ +#define LX_CONFIG(x) LX_##x = IS_BUILTIN(x) + +/* The build system will take care of deleting everything above this marker */ + + +import gdb diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py index d5943eca19cd..6e0b0afd888a 100644 --- a/scripts/gdb/vmlinux-gdb.py +++ b/scripts/gdb/vmlinux-gdb.py @@ -30,3 +30,4 @@ else: import linux.cpus import linux.lists import linux.proc + import linux.constants -- cgit From a84be61d0e38034634e7cbe076179cc6f1c16d22 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:42 -0700 Subject: scripts/gdb: provide kernel list item generators Facilitate linked-list items by providing a generator to return the dereferenced, and type-cast objects from a kernel linked list Link: http://lkml.kernel.org/r/2b0998564e6e5abe53585d466f87e491331fd2a4.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Cc: Jeff Mahoney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/lists.py | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/lists.py b/scripts/gdb/linux/lists.py index 3a3775bc162b..2f335fbd86fd 100644 --- a/scripts/gdb/linux/lists.py +++ b/scripts/gdb/linux/lists.py @@ -18,6 +18,27 @@ from linux import utils list_head = utils.CachedType("struct list_head") +def list_for_each(head): + if head.type == list_head.get_type().pointer(): + head = head.dereference() + elif head.type != list_head.get_type(): + raise gdb.GdbError("Must be struct list_head not {}" + .format(head.type)) + + node = head['next'].dereference() + while node.address != head.address: + yield node.address + node = node['next'].dereference() + + +def list_for_each_entry(head, gdbtype, member): + for node in list_for_each(head): + if node.type != list_head.get_type().pointer(): + raise TypeError("Type {} found. Expected struct list_head *." + .format(node.type)) + yield utils.container_of(node, gdbtype, member) + + def list_check(head): nb = 0 if (head.type == list_head.get_type().pointer()): -- cgit From 619ccaf3e94958485fd237000c24e06bce686bd2 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:45 -0700 Subject: scripts/gdb: convert modules usage to lists functions Simplify the module list functions with the new list_for_each_entry abstractions Link: http://lkml.kernel.org/r/ad0101c9391088608166fcec26af179868973d86.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/modules.py | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/modules.py b/scripts/gdb/linux/modules.py index 38f5d17044c5..62557ddf56f1 100644 --- a/scripts/gdb/linux/modules.py +++ b/scripts/gdb/linux/modules.py @@ -13,7 +13,7 @@ import gdb -from linux import cpus, utils +from linux import cpus, utils, lists module_type = utils.CachedType("struct module") @@ -23,12 +23,9 @@ def module_list(): global module_type module_ptr_type = module_type.get_type().pointer() modules = gdb.parse_and_eval("modules") - entry = modules['next'] - end_of_list = modules.address - while entry != end_of_list: - yield utils.container_of(entry, module_ptr_type, "list") - entry = entry['next'] + for module in lists.list_for_each_entry(modules, module_ptr_type, "list"): + yield module def find_module_by_name(name): @@ -80,17 +77,15 @@ class LxLsmod(gdb.Command): size=str(layout['size']), ref=str(module['refcnt']['counter'] - 1))) - source_list = module['source_list'] t = self._module_use_type.get_type().pointer() - entry = source_list['next'] first = True - while entry != source_list.address: - use = utils.container_of(entry, t, "source_list") + sources = module['source_list'] + for use in lists.list_for_each_entry(sources, t, "source_list"): gdb.write("{separator}{name}".format( separator=" " if first else ",", name=use['source']['name'].string())) first = False - entry = entry['next'] + gdb.write("\n") -- cgit From e78f3d70b3f5b045173961cb9cda16d005ecafa7 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:48 -0700 Subject: scripts/gdb: provide exception catching parser If we attempt to read a value that is not available to GDB, an exception is raised. Most of the time, this is a good thing; however on occasion we will want to be able to determine if a symbol is available. By catching the exception to simply return None, we can determine if we tried to read an invalid value, without the exception taking our execution context away from us Link: http://lkml.kernel.org/r/c72b25c06fc66e1d68371154097e2cbb112555d8.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/utils.py | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/utils.py b/scripts/gdb/linux/utils.py index 0893b326a28b..dbe2ad78048c 100644 --- a/scripts/gdb/linux/utils.py +++ b/scripts/gdb/linux/utils.py @@ -154,3 +154,10 @@ def get_gdbserver_type(): if gdbserver_type is not None and hasattr(gdb, 'events'): gdb.events.exited.connect(exit_handler) return gdbserver_type + + +def gdb_eval_or_none(expresssion): + try: + return gdb.parse_and_eval(expresssion) + except: + return None -- cgit From 958ef8a09a158d16cf398675c7bdfa3938472974 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:51 -0700 Subject: scripts/gdb: support !CONFIG_MODULES gracefully If CONFIG_MODULES is not enabled, lx-lsmod tries to find a non-existent symbol and generates an unfriendly traceback: (gdb) lx-lsmod Address Module Size Used by Traceback (most recent call last): File "scripts/gdb/linux/modules.py", line 75, in invoke for module in module_list(): File "scripts/gdb/linux/modules.py", line 24, in module_list module_ptr_type = module_type.get_type().pointer() File "scripts/gdb/linux/utils.py", line 28, in get_type self._type = gdb.lookup_type(self._name) gdb.error: No struct type named module. Error occurred in Python command: No struct type named module. Catch the error and return an empty module_list() for a clean command output as follows: (gdb) lx-lsmod Address Module Size Used by (gdb) Link: http://lkml.kernel.org/r/94d533819437408b85ae5864f939dd7ca6fbfcd6.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/modules.py | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/modules.py b/scripts/gdb/linux/modules.py index 62557ddf56f1..441b23239896 100644 --- a/scripts/gdb/linux/modules.py +++ b/scripts/gdb/linux/modules.py @@ -21,8 +21,11 @@ module_type = utils.CachedType("struct module") def module_list(): global module_type + modules = utils.gdb_eval_or_none("modules") + if modules is None: + return + module_ptr_type = module_type.get_type().pointer() - modules = gdb.parse_and_eval("modules") for module in lists.list_for_each_entry(modules, module_ptr_type, "list"): yield module -- cgit From 74627cf2df50bfc29f51341578038e284796a101 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:53 -0700 Subject: scripts/gdb: provide a dentry_name VFS path helper Walk the VFS entries, pre-pending the iname strings to generate a full VFS path name from a dentry. Link: http://lkml.kernel.org/r/4328fdb2d15ba7f1b21ad21c2eecc38d9cfc4d13.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/utils.py | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/utils.py b/scripts/gdb/linux/utils.py index dbe2ad78048c..de03a6b505bb 100644 --- a/scripts/gdb/linux/utils.py +++ b/scripts/gdb/linux/utils.py @@ -161,3 +161,11 @@ def gdb_eval_or_none(expresssion): return gdb.parse_and_eval(expresssion) except: return None + + +def dentry_name(d): + parent = d['d_parent'] + if parent == d or parent == 0: + return "" + p = dentry_name(d['d_parent']) + "/" + return p + d['d_iname'].string() -- cgit From e7165a2d7d87cd397d166ebf4d49763d28f5fc3d Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:56 -0700 Subject: scripts/gdb: add io resource readers Provide iomem_resource and ioports_resource printers and command hooks It can be quite interesting to halt the kernel as it's booting and check to see this list as it is being populated. It should be useful in the event that a kernel is not booting, you can identify what memory resources have been registered Link: http://lkml.kernel.org/r/f0a6b9fa9c92af4d7ed2e7343ccc84150e9c6fc5.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/proc.py | 57 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/proc.py b/scripts/gdb/linux/proc.py index 6e6709c1830c..d855b2fd9a06 100644 --- a/scripts/gdb/linux/proc.py +++ b/scripts/gdb/linux/proc.py @@ -39,3 +39,60 @@ class LxVersion(gdb.Command): gdb.write(gdb.parse_and_eval("linux_banner").string()) LxVersion() + + +# Resource Structure Printers +# /proc/iomem +# /proc/ioports + +def get_resources(resource, depth): + while resource: + yield resource, depth + + child = resource['child'] + if child: + for res, deep in get_resources(child, depth + 1): + yield res, deep + + resource = resource['sibling'] + + +def show_lx_resources(resource_str): + resource = gdb.parse_and_eval(resource_str) + width = 4 if resource['end'] < 0x10000 else 8 + # Iterate straight to the first child + for res, depth in get_resources(resource['child'], 0): + start = int(res['start']) + end = int(res['end']) + gdb.write(" " * depth * 2 + + "{0:0{1}x}-".format(start, width) + + "{0:0{1}x} : ".format(end, width) + + res['name'].string() + "\n") + + +class LxIOMem(gdb.Command): + """Identify the IO memory resource locations defined by the kernel + +Equivalent to cat /proc/iomem on a running target""" + + def __init__(self): + super(LxIOMem, self).__init__("lx-iomem", gdb.COMMAND_DATA) + + def invoke(self, arg, from_tty): + return show_lx_resources("iomem_resource") + +LxIOMem() + + +class LxIOPorts(gdb.Command): + """Identify the IO port resource locations defined by the kernel + +Equivalent to cat /proc/ioports on a running target""" + + def __init__(self): + super(LxIOPorts, self).__init__("lx-ioports", gdb.COMMAND_DATA) + + def invoke(self, arg, from_tty): + return show_lx_resources("ioport_resource") + +LxIOPorts() -- cgit From c1a153992ea86307d2b8c3c0be2e060102b02aff Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:24:59 -0700 Subject: scripts/gdb: add mount point list command lx-mounts will identify current mount points based on the 'init_task' namespace by default, as we do not yet have a kernel thread list implementation to select the current running thread. Optionally, a user can specify a PID to list from that process' namespace Link: http://lkml.kernel.org/r/e614c7bc32d2350b4ff1627ec761a7148e65bfe6.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/constants.py.in | 20 ++++++++ scripts/gdb/linux/proc.py | 99 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 119 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in index 79d9d0092452..7986f4e0da12 100644 --- a/scripts/gdb/linux/constants.py.in +++ b/scripts/gdb/linux/constants.py.in @@ -12,7 +12,11 @@ * */ +#include +#include + /* We need to stringify expanded macros so that they can be parsed */ + #define STRING(x) #x #define XSTRING(x) STRING(x) @@ -30,3 +34,19 @@ import gdb + +/* linux/fs.h */ +LX_VALUE(MS_RDONLY) +LX_VALUE(MS_SYNCHRONOUS) +LX_VALUE(MS_MANDLOCK) +LX_VALUE(MS_DIRSYNC) +LX_VALUE(MS_NOATIME) +LX_VALUE(MS_NODIRATIME) + +/* linux/mount.h */ +LX_VALUE(MNT_NOSUID) +LX_VALUE(MNT_NODEV) +LX_VALUE(MNT_NOEXEC) +LX_VALUE(MNT_NOATIME) +LX_VALUE(MNT_NODIRATIME) +LX_VALUE(MNT_RELATIME) diff --git a/scripts/gdb/linux/proc.py b/scripts/gdb/linux/proc.py index d855b2fd9a06..38b1f09d1cd9 100644 --- a/scripts/gdb/linux/proc.py +++ b/scripts/gdb/linux/proc.py @@ -12,6 +12,10 @@ # import gdb +from linux import constants +from linux import utils +from linux import tasks +from linux import lists class LxCmdLine(gdb.Command): @@ -96,3 +100,98 @@ Equivalent to cat /proc/ioports on a running target""" return show_lx_resources("ioport_resource") LxIOPorts() + + +# Mount namespace viewer +# /proc/mounts + +def info_opts(lst, opt): + opts = "" + for key, string in lst.items(): + if opt & key: + opts += string + return opts + + +FS_INFO = {constants.LX_MS_SYNCHRONOUS: ",sync", + constants.LX_MS_MANDLOCK: ",mand", + constants.LX_MS_DIRSYNC: ",dirsync", + constants.LX_MS_NOATIME: ",noatime", + constants.LX_MS_NODIRATIME: ",nodiratime"} + +MNT_INFO = {constants.LX_MNT_NOSUID: ",nosuid", + constants.LX_MNT_NODEV: ",nodev", + constants.LX_MNT_NOEXEC: ",noexec", + constants.LX_MNT_NOATIME: ",noatime", + constants.LX_MNT_NODIRATIME: ",nodiratime", + constants.LX_MNT_RELATIME: ",relatime"} + +mount_type = utils.CachedType("struct mount") +mount_ptr_type = mount_type.get_type().pointer() + + +class LxMounts(gdb.Command): + """Report the VFS mounts of the current process namespace. + +Equivalent to cat /proc/mounts on a running target +An integer value can be supplied to display the mount +values of that process namespace""" + + def __init__(self): + super(LxMounts, self).__init__("lx-mounts", gdb.COMMAND_DATA) + + # Equivalent to proc_namespace.c:show_vfsmnt + # However, that has the ability to call into s_op functions + # whereas we cannot and must make do with the information we can obtain. + def invoke(self, arg, from_tty): + argv = gdb.string_to_argv(arg) + if len(argv) >= 1: + try: + pid = int(argv[0]) + except: + raise gdb.GdbError("Provide a PID as integer value") + else: + pid = 1 + + task = tasks.get_task_by_pid(pid) + if not task: + raise gdb.GdbError("Couldn't find a process with PID {}" + .format(pid)) + + namespace = task['nsproxy']['mnt_ns'] + if not namespace: + raise gdb.GdbError("No namespace for current process") + + for vfs in lists.list_for_each_entry(namespace['list'], + mount_ptr_type, "mnt_list"): + devname = vfs['mnt_devname'].string() + devname = devname if devname else "none" + + pathname = "" + parent = vfs + while True: + mntpoint = parent['mnt_mountpoint'] + pathname = utils.dentry_name(mntpoint) + pathname + if (parent == parent['mnt_parent']): + break + parent = parent['mnt_parent'] + + if (pathname == ""): + pathname = "/" + + superblock = vfs['mnt']['mnt_sb'] + fstype = superblock['s_type']['name'].string() + s_flags = int(superblock['s_flags']) + m_flags = int(vfs['mnt']['mnt_flags']) + rd = "ro" if (s_flags & constants.LX_MS_RDONLY) else "rw" + + gdb.write( + "{} {} {} {}{}{} 0 0\n" + .format(devname, + pathname, + fstype, + rd, + info_opts(FS_INFO, s_flags), + info_opts(MNT_INFO, m_flags))) + +LxMounts() -- cgit From b1503934a5e51e74b2f4c72ad77b33231e7b6953 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:25:02 -0700 Subject: scripts/gdb: add cpu iterators The linux kernel provides macro's for iterating against values from the cpu_list masks. By providing some commonly used masks, we can mirror the kernels helper macros with easy to use generators. Link: http://lkml.kernel.org/r/d045c6599771ada1999d49612ee30fd2f9acf17f.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/cpus.py | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/cpus.py b/scripts/gdb/linux/cpus.py index 4297b83fedef..fc316fb3a3d4 100644 --- a/scripts/gdb/linux/cpus.py +++ b/scripts/gdb/linux/cpus.py @@ -100,6 +100,44 @@ def cpu_list(mask_name): yield cpu +def each_online_cpu(): + for cpu in cpu_list("__cpu_online_mask"): + yield cpu + + +def each_present_cpu(): + for cpu in cpu_list("__cpu_present_mask"): + yield cpu + + +def each_possible_cpu(): + for cpu in cpu_list("__cpu_possible_mask"): + yield cpu + + +def each_active_cpu(): + for cpu in cpu_list("__cpu_active_mask"): + yield cpu + + +class LxCpus(gdb.Command): + """List CPU status arrays + +Displays the known state of each CPU based on the kernel masks +and can help identify the state of hotplugged CPUs""" + + def __init__(self): + super(LxCpus, self).__init__("lx-cpus", gdb.COMMAND_DATA) + + def invoke(self, arg, from_tty): + gdb.write("Possible CPUs : {}\n".format(list(each_possible_cpu()))) + gdb.write("Present CPUs : {}\n".format(list(each_present_cpu()))) + gdb.write("Online CPUs : {}\n".format(list(each_online_cpu()))) + gdb.write("Active CPUs : {}\n".format(list(each_active_cpu()))) + +LxCpus() + + class PerCpu(gdb.Function): """Return per-cpu variable. -- cgit From 4bc393dbcf1915224e8947211a0ca906f9de7c56 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 23 May 2016 16:25:05 -0700 Subject: scripts/gdb: cast CPU numbers to integer We won't see more than 2 billion CPUs any time soon, and having cpu_list return long makes the output of lx-cpus a bit ugly. Link: http://lkml.kernel.org/r/dcb45c3b0a59e0fd321fa56ff7aa398458c689b3.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/cpus.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/cpus.py b/scripts/gdb/linux/cpus.py index fc316fb3a3d4..ca11e8df31b6 100644 --- a/scripts/gdb/linux/cpus.py +++ b/scripts/gdb/linux/cpus.py @@ -97,7 +97,7 @@ def cpu_list(mask_name): bits >>= 1 bit += 1 - yield cpu + yield int(cpu) def each_online_cpu(): -- cgit From e127a73d41ac471d7e3ba950cf128f42d6ee3448 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:25:07 -0700 Subject: scripts/gdb: add a Radix Tree Parser Linux makes use of the Radix Tree data structure to store pointers indexed by integer values. This structure is utilised across many structures in the kernel including the IRQ descriptor tables, and several filesystems. This module provides a method to lookup values from a structure given its head node. Usage: The function lx_radix_tree_lookup, must be given a symbol of type struct radix_tree_root, and an index into that tree. The object returned is a generic integer value, and must be cast correctly to the type based on the storage in the data structure. For example, to print the irq descriptor in the sparse irq_desc_tree at index 18, try the following: (gdb) print (struct irq_desc)$lx_radix_tree_lookup(irq_desc_tree, 18) Link: http://lkml.kernel.org/r/d2028c55e50cf95a9b7f8ca0d11885174b0cc709.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/constants.py.in | 7 +++ scripts/gdb/linux/radixtree.py | 97 +++++++++++++++++++++++++++++++++++++++ scripts/gdb/vmlinux-gdb.py | 1 + 3 files changed, 105 insertions(+) create mode 100644 scripts/gdb/linux/radixtree.py (limited to 'scripts/gdb') 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 #include +#include /* 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 +# +# 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. + +$lx_radix_tree_lookup(root_node [, index]): Return the node at the given index. +If index is omitted, the root node is dereferenced and returned.""" + + def __init__(self): + super(LxRadixTree, self).__init__("lx_radix_tree_lookup") + + def invoke(self, root, index=0): + result = lookup(root, index) + if result is None: + raise gdb.GdbError("No entry in tree at index {}".format(index)) + + return result + +LxRadixTree() diff --git a/scripts/gdb/vmlinux-gdb.py b/scripts/gdb/vmlinux-gdb.py index 6e0b0afd888a..3a80ad6eecad 100644 --- a/scripts/gdb/vmlinux-gdb.py +++ b/scripts/gdb/vmlinux-gdb.py @@ -31,3 +31,4 @@ else: import linux.lists import linux.proc import linux.constants + import linux.radixtree -- cgit From 9f66dee720984edcbc6ea07ad70fe5b8f0421c04 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:25:13 -0700 Subject: scripts/gdb: add lx_thread_info_by_pid helper The tasks module already provides helpers to find the task struct by pid, and the thread_info by task struct; however this is cumbersome to utilise on the gdb commandline. Wrap these two functionalities together in an extra single helper to allow exploring the thread info, from a PID value Link: http://lkml.kernel.org/r/dadc5667f053ec811eb3e3033d99d937fedbc93b.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/tasks.py | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/tasks.py b/scripts/gdb/linux/tasks.py index 862a4ae24d49..1bf949c43b76 100644 --- a/scripts/gdb/linux/tasks.py +++ b/scripts/gdb/linux/tasks.py @@ -114,3 +114,22 @@ variable.""" LxThreadInfoFunc() + + +class LxThreadInfoByPidFunc (gdb.Function): + """Calculate Linux thread_info from task variable found by pid + +$lx_thread_info_by_pid(PID): Given PID, return the corresponding thread_info +variable.""" + + def __init__(self): + super(LxThreadInfoByPidFunc, self).__init__("lx_thread_info_by_pid") + + def invoke(self, pid): + task = get_task_by_pid(pid) + if task: + return get_thread_info(task.dereference()) + else: + raise gdb.GdbError("No task of PID " + str(pid)) + +LxThreadInfoByPidFunc() -- cgit From 321958d9710c33e74ec98c0f3c96aa2a5dbe3008 Mon Sep 17 00:00:00 2001 From: Dom Cote Date: Mon, 23 May 2016 16:25:16 -0700 Subject: scripts/gdb: improve types abstraction for gdb python scripts Change the read_u16 function so it accepts both 'str' and 'byte' as type for the arguments. When calling read_memory() from gdb API, depending on if it was built with 2.7 or 3.X, the format used to return the data will differ ( 'str' for 2.7, and 'byte' for 3.X ). Add a function read_memoryview() to be able to get a 'memoryview' object back from read_memory() both with python 2.7 and 3.X . Tested with python 3.4 and 2.7 Tested with gdb 7.7 Link: http://lkml.kernel.org/r/73621f564503137a002a639d174e4fb35f73f462.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Dom Cote Tested-by: Kieran Bingham (Py2.7,Py3.4,GDB10) Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/utils.py | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/utils.py b/scripts/gdb/linux/utils.py index de03a6b505bb..50805874cfc3 100644 --- a/scripts/gdb/linux/utils.py +++ b/scripts/gdb/linux/utils.py @@ -87,11 +87,24 @@ def get_target_endianness(): return target_endianness +def read_memoryview(inf, start, length): + return memoryview(inf.read_memory(start, length)) + + def read_u16(buffer): + value = [0, 0] + + if type(buffer[0]) is str: + value[0] = ord(buffer[0]) + value[1] = ord(buffer[1]) + else: + value[0] = buffer[0] + value[1] = buffer[1] + if get_target_endianness() == LITTLE_ENDIAN: - return ord(buffer[0]) + (ord(buffer[1]) << 8) + return value[0] + (value[1] << 8) else: - return ord(buffer[1]) + (ord(buffer[0]) << 8) + return value[1] + (value[0] << 8) def read_u32(buffer): -- cgit From d21d5b9eb0e1e492232a3b56d0cc03bcdaa7ee17 Mon Sep 17 00:00:00 2001 From: Dom Cote Date: Mon, 23 May 2016 16:25:19 -0700 Subject: scripts/gdb: fix issue with dmesg.py and python 3.X When built against Python 3, GDB differs in the return type for its read_memory function, causing the lx-dmesg command to fail. Now that we have an improved read_16() we can use the new read_memoryview() abstraction to make lx-dmesg return valid data on both current Python APIs Tested with python 3.4 and 2.7 Tested with gdb 7.7 Link: http://lkml.kernel.org/r/28477b727ff7fe3101fd4e426060e8a68317a639.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Dom Cote [kieran@bingham.xyz: Adjusted commit log to better reflect code changes] Tested-by: Kieran Bingham (Py2.7,Py3.4,GDB10) Signed-off-by: Kieran Bingham Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/dmesg.py | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/dmesg.py b/scripts/gdb/linux/dmesg.py index 927d0d2a3145..04d6719067f2 100644 --- a/scripts/gdb/linux/dmesg.py +++ b/scripts/gdb/linux/dmesg.py @@ -33,11 +33,12 @@ class LxDmesg(gdb.Command): if log_first_idx < log_next_idx: log_buf_2nd_half = -1 length = log_next_idx - log_first_idx - log_buf = inf.read_memory(start, length) + log_buf = utils.read_memoryview(inf, start, length).tobytes() else: log_buf_2nd_half = log_buf_len - log_first_idx - log_buf = inf.read_memory(start, log_buf_2nd_half) + \ - inf.read_memory(log_buf_addr, log_next_idx) + a = utils.read_memoryview(inf, start, log_buf_2nd_half) + b = utils.read_memoryview(inf, log_buf_addr, log_next_idx) + log_buf = a.tobytes() + b.tobytes() pos = 0 while pos < log_buf.__len__(): -- cgit From b3b08429857b209d8bb9785a15b8247421bf4973 Mon Sep 17 00:00:00 2001 From: Kieran Bingham Date: Mon, 23 May 2016 16:25:21 -0700 Subject: scripts/gdb: decode bytestream on dmesg for Python3 The recent fixes to lx-dmesg, now allow the command to print successfully on Python3, however the python interpreter wraps the bytes for each line with a b'' marker. To remove this, we need to decode the line, where .decode() will default to 'UTF-8' Link: http://lkml.kernel.org/r/d67ccf93f2479c94cb3399262b9b796e0dbefcf2.1462865983.git.jan.kiszka@siemens.com Signed-off-by: Kieran Bingham Acked-by: Dom Cote Tested-by: Dom Cote Signed-off-by: Jan Kiszka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/dmesg.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'scripts/gdb') diff --git a/scripts/gdb/linux/dmesg.py b/scripts/gdb/linux/dmesg.py index 04d6719067f2..f9b92ece7834 100644 --- a/scripts/gdb/linux/dmesg.py +++ b/scripts/gdb/linux/dmesg.py @@ -51,10 +51,10 @@ class LxDmesg(gdb.Command): continue text_len = utils.read_u16(log_buf[pos + 10:pos + 12]) - text = log_buf[pos + 16:pos + 16 + text_len] + text = log_buf[pos + 16:pos + 16 + text_len].decode() time_stamp = utils.read_u64(log_buf[pos:pos + 8]) - for line in memoryview(text).tobytes().splitlines(): + for line in text.splitlines(): gdb.write("[{time:12.6f}] {line}\n".format( time=time_stamp / 1000000000.0, line=line)) -- cgit