I believe that this should be tested for permissions checks. I honestly do not believe that it would be a good idea to always clear the ringbuffer seeing as how on some systems this command requires root level permissions.
On Tue, Feb 4, 2014 at 12:28 PM, Ilia Mirkin <[email protected]> wrote: > On Tue, Feb 4, 2014 at 1:12 PM, Dylan Baker <[email protected]> wrote: >> On Tuesday, February 04, 2014 12:43:42 PM Ilia Mirkin wrote: >>> On Tue, Feb 4, 2014 at 12:35 PM, Dylan Baker <[email protected]> >> wrote: >>> > This modules implements two classes and a helper function. The two >>> > classes are both dmesg wrapper classes, one, PosixDmesg is used on posix >>> > systems when requested to actually do checks on dmesg. The second class, >>> > DummyDmesg, is used to reduce code complexity by providing dummy >>> > versions of the methods in PosixDmesg. This means that we don't need >>> > separate code paths for Posix systems wanting to check dmesg, Posix >>> > systems not wanting to check dmesg, and non-posix systems which lack >>> > dmesg. >>> > >>> > Beyond reducing complexity this module also gives better isolation, >>> > dmesg is only used in Test.execute(), no where else. Additional classes >>> > don't need to worry about dmesg that way, it's just available. >>> > >>> > v2: - Remove unnecessary assert from PosixDmesg.update_result() >>> > >>> > - simplify replace helper in PoixDmesg.update_result() >>> > - replace try/except with if check >>> > - Change PosixDmesg.update_dmesg() to work even if dmesg 'wraps' >>> > >>> > v3: - Try/Except assignment of PosixDmesg._last_message in update_dmesg() >>> > >>> > - Set the dmesg levels the same as the previous implementation >>> > - Change PosixDmesg into LinuxDmesg and enforce that dmesg has >>> > >>> > timestamps >>> > >>> > v4: - Add check in LinuxDmesg.__init__ to ensure there is something in >>> > >>> > dmesg before doing the timestamp check. This should make problems >>> > clearer >>> > >>> > - Refactor some code in LinuxDmesg.update_result() >>> > >>> > v5: - Replace exception with warning. >>> > >>> > - add break to loop in dmesg.update_dmesg >>> > >>> > Signed-off-by: Dylan Baker <[email protected]> >>> > --- >>> > >>> > framework/dmesg.py | 175 >>> > +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, >>> > 175 insertions(+) >>> > create mode 100644 framework/dmesg.py >>> > >>> > diff --git a/framework/dmesg.py b/framework/dmesg.py >>> > new file mode 100644 >>> > index 0000000..feb05ad >>> > --- /dev/null >>> > +++ b/framework/dmesg.py >>> > @@ -0,0 +1,175 @@ >>> > +# Copyright (c) 2013-2014 Intel Corporation >>> > +# >>> > +# Permission is hereby granted, free of charge, to any person obtaining a >>> > +# copy of this software and associated documentation files (the >>> > "Software"), +# to deal in the Software without restriction, including >>> > without limitation +# the rights to use, copy, modify, merge, publish, >>> > distribute, sublicense, +# and/or sell copies of the Software, and to >>> > permit persons to whom the +# Software is furnished to do so, subject to >>> > the following conditions: +# >>> > +# The above copyright notice and this permission notice (including the >>> > next +# paragraph) shall be included in all copies or substantial >>> > portions of the +# Software. >>> > +# >>> > +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS >>> > OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF >>> > MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. >>> > IN NO EVENT SHALL +# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY >>> > CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, >>> > TORT OR OTHERWISE, ARISING +# FROM, OUT OF OR IN CONNECTION WITH THE >>> > SOFTWARE OR THE USE OR OTHER DEALINGS +# IN THE SOFTWARE. >>> > + >>> > +""" Module implementing classes for reading posix dmesg >>> > + >>> > +Currently this module only has the default DummyDmesg, and a LinuxDmesg. >>> > +The method used on Linux requires that timetamps are enabled, and no >>> > other >>> > +posix system has timestamps. >>> > + >>> > +On OSX and *BSD one would likely want to implement a system that reads >>> > the >>> > +sysloger, since timestamps can be added by the sysloger, and are not >>> > inserted +by dmesg. >>> > + >>> > +""" >>> > + >>> > +import re >>> > +import sys >>> > +import subprocess >>> > +import warnings >>> > + >>> > +__all__ = ['LinuxDmesg', 'DummyDmesg', 'get_dmesg'] >>> > + >>> > + >>> > +class LinuxDmesg(object): >>> > + """ Read dmesg on posix systems >>> > + >>> > + This reads the dmesg ring buffer, stores the contents of the buffer, >>> > and + then compares it whenever called, returning the difference >>> > between the + calls. It requires timestamps to be enabled. >>> > + >>> > + """ >>> > + DMESG_COMMAND = ['dmesg', '--level', >>> > 'emerg,alert,crit,err,warn,notice'] + >>> > + def __init__(self): >>> > + """ Create a dmesg instance """ >>> > + self._last_message = None >>> > + self._new_messages = [] >>> > + >>> > + # Populate self.dmesg initially, otherwise the first test will >>> > always + # be full of dmesg crud. >>> > + self.update_dmesg() >>> > + >>> > + if not self._last_message: >>> > + # We need to ensure that there is something in dmesg to check >>> > + # timestamps. >>> > + warnings.warn("Cannot check dmesg for timestamp support. If >>> > you " + "do not have timestamps enabled in your >>> > kernel you " + "get incomplete dmesg captures", >>> > RuntimeWarning) + elif not re.match(r'\[\s*\d+\.\d+\]', >>> > self._last_message): + # Do an initial check to ensure that >>> > dmesg has timestamps, we need + # timestamps to work >>> > correctly. A proper linux dmesg timestamp + # looks like this: >>> > [ 0.00000] >>> > + raise DmesgError( >>> > + "Your kernel does not seem to support timestamps, which " >>> > + "are required by the --dmesg option") >>> >>> Consider also making this a warning. >>> >>> Either way, Reviewed-by: Ilia Mirkin <[email protected]> >>> >>> > + >>> > + def update_result(self, result): >>> > + """ Takes a TestResult object and updates it with dmesg statuses >>> > + >>> > + If dmesg is enabled, and if dmesg has been updated, then replace >>> > pass + with dmesg-warn and warn and fail with dmesg-fail. If dmesg >>> > has not + been updated, it will return the original result passed >>> > in. + >>> > + Arguments: >>> > + result -- A TestResult instance >>> > + >>> > + """ >>> > + >>> > + def replace(res): >>> > + """ helper to replace statuses with the new dmesg status >>> > + >>> > + Replaces pass with dmesg-warn, and warn and fail with >>> > dmesg-fail, + otherwise returns the input >>> > + >>> > + """ >>> > + return {"pass": "dmesg-warn", >>> > + "warn": "dmesg-fail", >>> > + "fail": "dmesg-fail"}.get(res, res) >>> > + >>> > + # Get a new snapshot of dmesg >>> > + self.update_dmesg() >>> > + >>> > + # if update_dmesg() found new entries replace the results of the >>> > test + # and subtests >>> > + if self._new_messages: >>> > + result['result'] = replace(result['result']) >>> > + >>> > + # Replace any subtests >>> > + if 'subtest' in result: >>> > + for key, value in result['subtest'].iteritems(): >>> > + result['subtest'][key] = replace(value) >>> > + >>> > + # Add the dmesg values to the result >>> > + result['dmesg'] = self._new_messages >>> > + >>> > + return result >>> > + >>> > + def update_dmesg(self): >>> > + """ Call dmesg using subprocess.check_output >>> > + >>> > + Get the contents of dmesg, then calculate new messages, finally >>> > set + self.dmesg equal to the just read contents of dmesg. >>> > + >>> > + """ >>> > + dmesg = >>> > subprocess.check_output(self.DMESG_COMMAND).strip().splitlines() + >>> > + # Find all new entries, do this by slicing the list of dmesg to >>> > only + # returns elements after the last element stored. If there >>> > are not + # matches a value error is raised, that means all of >>> > dmesg is new + l = 0 >>> > + for index, item in enumerate(reversed(dmesg)): >>> > + if item == self._last_message: >>> > + l = len(dmesg) - index # don't include the matched >>> > element + break >>> > + self._new_messages = dmesg[l:] >>> > + >>> > + # Attempt to store the last element of dmesg, unless there was no >>> > dmesg + self._last_message = dmesg[-1] if dmesg else None >>> > + >>> > + >>> > +class DummyDmesg(object): >>> > + """ An dummy class for dmesg on non unix-like systems >>> > + >>> > + This implements a dummy version of the LinuxDmesg, and can be used >>> > anytime + it is not desirable to actually read dmesg, such as >>> > non-posix systems, or + when the contents of dmesg don't matter. >>> > + >>> > + """ >>> > + DMESG_COMMAND = [] >>> > + >>> > + def __init__(self): >>> > + pass >>> > + >>> > + def update_dmesg(self): >>> > + """ Dummy version of update_dmesg """ >>> > + pass >>> > + >>> > + def update_result(self, result): >>> > + """ Dummy version of update_result """ >>> > + return result >>> > + >>> > + >>> > +class DmesgError(EnvironmentError): >>> > + pass >>> > + >>> > + >>> > +def get_dmesg(not_dummy=True): >>> > + """ Return a Dmesg type instance >>> > + >>> > + Normally this does a system check, and returns the type that proper >>> > for + your system. However, if Dummy is True then it will always >>> > return a + DummyDmesg instance. >>> > + >>> > + """ >>> > + if sys.platform.startswith('linux') and not_dummy: >>> > + return LinuxDmesg() >>> > + return DummyDmesg() >>> > -- >>> > 1.8.5.3 >>> > >>> > _______________________________________________ >>> > Piglit mailing list >>> > [email protected] >>> > http://lists.freedesktop.org/mailman/listinfo/piglit >> >> Is that review for the series? > > It's a review for this patch. I believe I also reviewed 3/4 and 4/4 > earlier on (and those reviews should still stand). 2/4 uses some fancy > testing framework I'm not familiar with, so I haven't looked at it. > But the impact is also low, so probably fine to commit unreviewed? > Dunno what the policy is. > _______________________________________________ > Piglit mailing list > [email protected] > http://lists.freedesktop.org/mailman/listinfo/piglit _______________________________________________ Piglit mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/piglit
