Request for review: 8006298: Specifying malformed JFR options (--XX:+FlightRecorderOptions) outputs non-sensical error
harold seigel
harold.seigel at oracle.com
Tue Feb 5 11:11:41 PST 2013
Hi,
Please review the back port to 7 of the fix for bug 8006298. The
changes are similar to the original bug fix.
http://cr.openjdk.java.net/~hseigel/bug_8006298_7u/
<http://cr.openjdk.java.net/%7Ehseigel/bug_8006298_7u/>
Thanks, Harold
On 1/31/2013 1:40 PM, Mikael Vidstedt wrote:
>
> Thanks Harold!
>
> Cheers,
> Mikael
>
> On 2013-01-31 10:39, harold seigel wrote:
>> Good catch!
>>
>> I'll change it to strchr() before checking it in.
>>
>> Thanks, Harold
>>
>> On 1/31/2013 12:34 PM, Mikael Vidstedt wrote:
>>>
>>>
>>> Harold,
>>>
>>> Thanks for making the changes. One further question (sorry for not
>>> asking this the first time around):
>>>
>>> Is there a fundamental reason for finding the last equals ('=')
>>> instead of the first one - i.e. would it make more sense to use
>>> strchr instead of strrchr? Not that I think we have any options that
>>> accept multiple equals today, but...
>>>
>>> Cheers,
>>> Mikael
>>>
>>> On 2013-01-31 06:55, harold seigel wrote:
>>>> Hi,
>>>>
>>>> Thank you for your comments!
>>>>
>>>> Please review this updated webrev:
>>>> http://cr.openjdk.java.net/~hseigel/bug_8006298_2/
>>>> <http://cr.openjdk.java.net/%7Ehseigel/bug_8006298_2/>
>>>>
>>>> It avoids the 'const' and '\0' issues by determining the length of
>>>> the argument and passing it to find_flag().
>>>>
>>>> This changes the output messages slightly, by including the '=...'
>>>> text. For example:
>>>>
>>>> % $JAVA_HOME/bin/java -XX:+UseLargePages=8 -version
>>>> Improperly specified VM option 'UseLargePages=8'
>>>>
>>>> % $JAVA_HOME/bin/java -XX:-ObjectAlignmentInBytes=16 -version
>>>> Unexpected +/- setting in VM option 'ObjectAlignmentInBytes=16'
>>>>
>>>> Thanks, Harold
>>>>
>>>>
>>>> On 1/30/2013 10:39 PM, Vitaly Davidovich wrote:
>>>>>
>>>>> I'd also change "equal_sign[0] = 0;" to "equal_sign[0] = '\0';" if
>>>>> this line is to be kept - it's more idiomatic.
>>>>>
>>>>> Thanks
>>>>>
>>>>> Sent from my phone
>>>>>
>>>>> On Jan 30, 2013 8:34 PM, "Mikael Vidstedt"
>>>>> <mikael.vidstedt at oracle.com <mailto:mikael.vidstedt at oracle.com>>
>>>>> wrote:
>>>>>
>>>>>
>>>>> Harold,
>>>>>
>>>>> Thanks for doing this, I like the improved messages a lot!
>>>>>
>>>>> One small question:
>>>>>
>>>>> The first argument to process_argument is a "const char* arg".
>>>>> argname is also const, based on arg. You do this:
>>>>>
>>>>> char* equal_sign = (char *)strrchr(argname, '=');
>>>>> if (equal_sign > argname)
>>>>> equal_sign[0] = 0;
>>>>>
>>>>> Doesn't that effectively break the const'ness of the incoming
>>>>> argument?
>>>>>
>>>>> Cheers,
>>>>> Mikael
>>>>>
>>>>> On 2013-01-30 10:51, harold seigel wrote:
>>>>>> Hi,
>>>>>>
>>>>>> Please review the following change to fix bug 8006298.
>>>>>>
>>>>>> Summary:
>>>>>> This change enables hotspot to emit more useful messages when
>>>>>> Java options are specified incorrectly.
>>>>>>
>>>>>> This was tested using JCK, UTE, and JTREG tests, and by
>>>>>> hand. Below are the test cases that were run by hand.
>>>>>> Please let me know if you have any additional suggestions.
>>>>>> (The "Error:..." messages appeared in all cases but are only
>>>>>> shown for the initial case.)
>>>>>>
>>>>>> $JAVA_HOME/bin/java -XX:UseLargePages -version
>>>>>> Missing +/- setting for VM option 'UseLargePages'
>>>>>> Error: Could not create the Java Virtual Machine.
>>>>>> Error: A fatal exception has occurred. Program will exit.
>>>>>>
>>>>>> $JAVA_HOME/bin/java -XX:+UseLargePages=8 -version
>>>>>> Improperly specified VM option 'UseLargePages'
>>>>>>
>>>>>> $JAVA_HOME/bin/java -XX:ObjectAlignmentInBytes=v -version
>>>>>> Improperly specified VM option 'ObjectAlignmentInBytes'
>>>>>>
>>>>>> $JAVA_HOME/bin/java -XX:-ObjectAlignmentInBytes=16 -version
>>>>>> Unexpected +/- setting in VM option
>>>>>> 'ObjectAlignmentInBytes' <-- 64 bit VM's
>>>>>> Unrecognized VM option 'ObjectAlignmentInBytes' <-- 32
>>>>>> bit VM's
>>>>>>
>>>>>> $JAVA_HOME/bin/java -XX:bogus_option -version
>>>>>> Unrecognized VM option 'bogus_option'
>>>>>>
>>>>>> Open webrev at
>>>>>> http://cr.openjdk.java.net/~hseigel/bug_8006298/
>>>>>> <http://cr.openjdk.java.net/%7Ehseigel/bug_8006298/>
>>>>>>
>>>>>> Bug link at http://bugs.sun.com/view_bug.do?bug_id=8006298
>>>>>>
>>>>>> Thanks! Harold
>>>>>
>>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/attachments/20130205/ea2c4cfb/attachment-0001.html
More information about the hotspot-runtime-dev
mailing list