Re: [PATCH 3/5] scripts/gdb: Add io resource readers

From: Jan Kiszka
Date: Sat Jan 23 2016 - 10:12:54 EST


On 2016-01-20 12:15, Kieran Bingham wrote:
> Provide iomem_resource and ioports_resource printers and command hooks
>
> Signed-off-by: Kieran Bingham <kieran.bingham@xxxxxxxxxx>
>
> ---
>
> These two readers are a useful extract of kernel information.
> This shows the power of having these commands in gdb/scripts as you can
> halt a kernel as it's booting and read these as the structures grow.
>
> It should be useful in the event that a kernel is not booting, you
> can identify what memory resources have been registered
>

Ack. Maybe provide this reasoning in the commit log? I explains why we
want this which is too often lacking in the persistent logs...

>
>
> scripts/gdb/linux/proc.py | 57 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 57 insertions(+)
>
> 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()
>

Looks good to me.

Jan

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