logging fixes for last pre-ZBB JDK7-TL snapshot (6977677, 7016208, 7041595)
David Holmes
David.Holmes at oracle.com
Mon May 16 19:00:49 PDT 2011
Dan,
I'm sorry this didn't come through in time ...
Mandy Chung said the following on 05/17/11 05:22:
> Logger.java
> Looks good. The removal of the synchronization required by
> Logger.getLogger fixes the deadlock issue.
But this method now has a race condition:
372 // Synchronization is not required here. All synchronization for
373 // adding a new Logger object is handled by
LogManager.addLogger().
374 public static Logger getLogger(String name, String
resourceBundleName) {
375 LogManager manager = LogManager.getLogManager();
376 Logger result = manager.demandLogger(name);
377 if (result.resourceBundleName == null) {
378 // Note: we may get a MissingResourceException here.
379 result.setupResourceInfo(resourceBundleName);
380 } else if
(!result.resourceBundleName.equals(resourceBundleName)) {
381 throw new
IllegalArgumentException(result.resourceBundleName +
382 " != " + resourceBundleName);
383 }
384 return result;
385 }
Two threads calling this method with the same name but different
resource bundle names can both see null at line 377 and install their
different resource bundles. That section needs to be atomic.
David
-----
>
> LogManager.java
> Retrying in a while loop is one way to fix weak ref / gc timing issue.
> What about if you refactor the addLogger method to add a new private
> private method equivalent to addLogger (say add(Logger)) that will
> return
> logger if added successfully or null if not.
>
> The addLogger method will return add(logger) != logger. The
> synchronization
> will be done in the new add method.
>
> Would this fix 7016208? It seems to me that addLogger returning
> boolean
> is the cause for this bug.
>
> Mandy
>
> On 05/15/11 11:40, Daniel D. Daugherty wrote:
>> Greetings,
>>
>> The final pre-ZBB JDK7-TL snapshot is happening @ 1700 PT on
>> Monday, May 14, 2011. This snapshot is targeted for JDK7-B143
>> or JDK7-B144 (I'm not sure which). Yes, we're still trying to
>> figure out how to merge our JDK & HotSpot Express processes
>> with Oracle processes. Please be patient while we iron out the
>> wrinkles...
>>
>> I have three bug fixes for the java.util.logging area:
>>
>> 6977677 3/2 Deadlock on logging subsystem initialization
>> 7016208 4/3 null sometimes returned by java.util.logging.Logger.
>> getLogger(String name) in -server -Xcomp
>> 7041595 4/4 add lost test for 6487638
>>
>> 6977677 is a deadlock between java.util.logging.Logger.getLogger()
>> and LogManager.<clinit> via a PlatformLogger. This fix involves:
>>
>> src/share/classes/java/util/logging/Logger.java
>> test/java/util/logging/LoggingDeadlock4.java
>>
>> Mandy, I would like your review of the above bug fix.
>>
>> 7016208 is an unexpected null return from Logger.getLogger() due to
>> the lack of a strong reference. This fix involves:
>>
>> src/share/classes/java/util/logging/LogManager.java
>>
>> Tom R., I would like your review of the above bug fix.
>>
>> 7041595 is just pushing a Logging deadlock test that got lost a
>> long time ago. This fix involves:
>>
>> test/java/util/logging/LoggingDeadlock3.java
>> test/java/util/logging/LoggingDeadlock3.props
>>
>> Because I'm fixing a deadlock in 6977677, I wanted to make sure
>> that this Logging deadlock test was back in the mix.
>>
>> Here is the webrev URL:
>>
>> http://cr.openjdk.java.net/~dcubed/logging-batch-20110515-webrev/0/
>>
>> The comments that I added to the code changes should make the
>> reason(s) for the code changes pretty self explanatory.
>>
>> These changes have been run through JPRT and pass the "jdk_util"
>> tests on all platforms. I have also run SDK/JDK logging tests
>> and the VM/NSK logging tests on the following configs:
>>
>> Solaris X86 * {Client VM, Server VM} product * {-Xmixed, -Xcomp}
>> WinXP * {Client VM, Server VM} product * {-Xmixed, -Xcomp}
>>
>> Here is the summary from Solaris X86:
>>
>> Summary of Test Results (8 result dirs)
>> =========================================
>> all executed: 2264 all passed: 2264 all ignored: 0 all failed: 0
>> time: 0 hour(s) 17 minute(s)
>>
>> Here is the partial summary (6 of 8) from WinXP:
>>
>> Summary of Test Results (6 result dirs)
>> =========================================
>> all executed: 1160 all passed: 1160 all ignored: 0 all failed: 0
>> time: 1 hour(s) 0 minute(s)
>>
>> The last two VM/NSK test runs are still going; yes, WinXP is slower than
>> Solaris X86...
>>
>> Thanks, in advance, for any reviews.
>>
>> Dan
>>
>
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