On 2015/3/24 17:51, Ian Campbell wrote:
On Tue, 2015-03-24 at 16:47 +0800, Chen, Tiejun wrote:
All guys,
Thanks for your reply.
Sorry to bother you.
I have a question to two files, tools/python/xen/lowlevel/xc/xc.c and
tools/python/xen/lowlevel/xl/xl.c. Who is a caller to those methods like
pyxc_methods[] and pyxl_methods[]?
They are registered with the Python runtime, so they are called from
Python code. The first member of the struct is the pythonic function
Sorry I don't understanding this. So seems you mean instead of xl, this
is called by the third party user with python?
name, e.g. from xc.c:
{ "domain_create",
Otherwise, often we always perform `xl create xxx' to create a VM. So I
think this should go into this flow like this,
xl_cmdtable.c:main_create()
|
+ create_domain()
|
+ libxl_domain_create_new()
|
+ do_domain_create()
|
+ ....
Right?
(PyCFunction)pyxc_domain_create,
So I don't see 'pyxc_domain_create' is called. Or I'm missing something...
METH_VARARGS | METH_KEYWORDS, "\n"
"Create a new domain.\n"
" dom [int, 0]: Domain identifier to use (allocated if
zero).\n"
"Returns: [int] new domain identifier; -1 on error.\n" },
defines a method called domain_create, in the xen.lowlevel.xc namespace.
And how should we call these approaches?
I'm not sure what you are asking here.
If you can give a real case to call this, things couldn't be better :)
In my specific case, I'm trying to introduce a new flag to each a device
while assigning device. So this means I have to add a parameter, 'flag',
into
int xc_assign_device(
xc_interface *xch,
uint32_t domid,
uint32_t machine_sbdf)
Then this is extended as
int xc_assign_device(
xc_interface *xch,
uint32_t domid,
uint32_t machine_sbdf,
uint32_t flag)
After this introduction, obviously I should cover all cases using
xc_assign_device(). And also I found this fallout goes into these two
files. For example, here pyxc_assign_device() is involved. Currently it
has two parameters, 'dom' and 'pci_str', and as I understand 'pci_str'
should represent all pci devices with SBDF format, right?
It appears so, yes.
But I don't know exactly what rule should be complied to construct this
sort of flag into 'pci_str', or any reasonable idea to achieve my goal?
If it is non-trivial to fix them IMHO it is acceptable for the new
parameter to not be plumbed up to the Python bindings until someone
comes along with a requirement to use it from Python. IOW you can just
pass whatever the nop value is for the new argument.
Should I extend this 'pci_str' like "Seg,bus,device,function:flag"? But
I'm not sure if I'm breaking the existing usage since like I said, I
don't know what scenarios are using these methods.
Thanks
Tiejun
