scripts/tracetool/vcpu.py

   1 # -*- coding: utf-8 -*-
   2
   3 """
   4 Generic management for the 'vcpu' property.
   5
   6 """
   7
   8 __author__     = "Lluís Vilanova <vilanova@ac.upc.edu>"
   9 __copyright__  = "Copyright 2016, Lluís Vilanova <vilanova@ac.upc.edu>"
  10 __license__    = "GPL version 2 or (at your option) any later version"
  11
  12 __maintainer__ = "Stefan Hajnoczi"
  13 __email__      = "stefanha@redhat.com"
  14
  15
  16 from tracetool import Arguments, try_import
  17
  18
  19 def transform_event(event):
  20     """Transform event to comply with the 'vcpu' property (if present)."""
  21     if "vcpu" in event.properties:
  22         # events with 'tcg-trans' and 'tcg-exec' are auto-generated from
  23         # already-patched events
  24         assert "tcg-trans" not in event.properties
  25         assert "tcg-exec" not in event.properties
  26
  27         event.args = Arguments([("void *", "__cpu"), event.args])
  28         if "tcg" in event.properties:
  29             fmt = "\"cpu=%p \""
  30             event.fmt = [fmt + event.fmt[0],
  31                          fmt + event.fmt[1]]
  32         else:
  33             fmt = "\"cpu=%p \""
  34             event.fmt = fmt + event.fmt
  35     return event
  36
  37
  38 def transform_args(format, event, *args, **kwargs):
  39     """Transforms the arguments to suit the specified format.
  40
  41     The format module must implement function 'vcpu_args', which receives the
  42     implicit arguments added by the 'vcpu' property, and must return suitable
  43     arguments for the given format.
  44
  45     The function is only called for events with the 'vcpu' property.
  46
  47     Parameters
  48     ==========
  49     format : str
  50         Format module name.
  51     event : Event
  52     args, kwargs
  53         Passed to 'vcpu_transform_args'.
  54
  55     Returns
  56     =======
  57     Arguments
  58         The transformed arguments, including the non-implicit ones.
  59
  60     """
  61     if "vcpu" in event.properties:
  62         ok, func = try_import("tracetool.format." + format,
  63                               "vcpu_transform_args")
  64         assert ok
  65         assert func
  66         return Arguments([func(event.args[:1], *args, **kwargs),
  67                           event.args[1:]])
  68     else:
  69         return event.args