Greetings,
I've updated the fix due to comments in Code Review Round 0.
Here is a summary of changes made to the various files:
src/share/vm/oops/cpCacheOop.cpp (HSX-23.6, HSX-24)
src/share/vm/oops/cpCache.cpp (HSX-25)
src/share/vm/oops/klassVtable.cpp
- removed the new RC_TRACE_NO_CR() macro calls at Coleen's
request;
these files are outside of JVM/TI RedefineClasses proper so the
tracing/debug style should not be dictated by JVM/TI
RedefineClasses
style that is currently in use
- did not touch the existing RC_TRACE... macros in the file;
removing
the existing macro calls would be outside the scope of this bug
src/share/vm/oops/cpCacheOop.cpp (HSX-23.6, HSX-24)
src/share/vm/oops/cpCache.cpp (HSX-25)
- copy a comment from
ConstantPoolCacheEntry::is_interesting_method_entry()
to ConstantPoolCacheEntry::check_no_old_or_obsolete_entries()
src/share/vm/oops/klassVtable.cpp
- Copied the new comment intended to prevent the "break" from
re-materializing again from klassItable::adjust_method_entries()
to klassVtable::adjust_method_entries(); yes, I'm paranoid.
In the HSX-25 version only:
src/share/vm/oops/metadata.hpp
- revert changes
src/share/vm/oops/cpCacheOop.cpp
src/share/vm/oops/klassVtable.cpp
- wrap uses of is_valid() in NOT_PRODUCT macro as appropriate
Here are the URLs for the updated webrevs:
http://cr.openjdk.java.net/~dcubed/7182152-webrev/1-hsx23.6/
http://cr.openjdk.java.net/~dcubed/7182152-webrev/1-hsx24/
http://cr.openjdk.java.net/~dcubed/7182152-webrev/1-hsx25/
The JPDA stack testing that I started on Friday is still running on
WinXP so I'm blocked for checking the recompile due to these
changes.
I'll start a recompile on Solaris X86, but that will take some time.
Thanks, in advance, for more comments, suggestions or questions.
Dan
On 2/1/13 12:55 PM, Daniel D. Daugherty wrote:
Greetings,
I have a fix for the following JVM/TI bug:
7182152 Instrumentation hot swap test incorrect monitor count
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7182152
https://jbs.oracle.com/bugs/browse/JDK-7182152
The fix for the bug in the product code is one line:
src/share/vm/oops/klassVtable.cpp:
@@ -992,18 +1020,50 @@
// RC_TRACE macro has an embedded ResourceMark
RC_TRACE(0x00200000, ("itable method update: %s(%s)",
new_method->name()->as_C_string(),
new_method->signature()->as_C_string()));
}
- break;
+ // cannot 'break' here; see for-loop comment above.
}
ime++;
}
}
}
and is applicable to JDK7u10/HSX-23.6 and JDK7u14/HSX-24. Coleen
already fixed the bug as part of the Perm Gen Removal (PGR) project
in HSX-25. Yes, we found a 1-line bug fix buried in the monster PGR
changeset. Many thanks to Coleen for her help in this bug hunt!
The rest of the code in the webrevs are:
- additional JVM/TI tracing code backported from Coleen's PGR
changeset
- additional JVM/TI tracing code added by me and forward ported
to HSX-25
- a new -XX:TraceRedefineClasses=16384 flag value for finding these
elusive old or obsolete methods
- exposure of some printing code to the PRODUCT build so that
the new
tracing is available in a PRODUCT build
You might be wondering why the new tracing code is exposed in a
PRODUCT
build. Well, it appears that more and more PRODUCT bits
deployments are
using JVM/TI RedefineClasses() and/or RetransformClasses() at
run-time
to instrument their systems. This bug (7182152) was only
intermittently
reproducible in the WLS environment in which it occurred so I
made the
tracing available in a PRODUCT build to assist in the hunt.
Raj from the WLS team has also verified that the HSX-23.6
version of
fix resolves the issue in his environment. Thanks Raj!
Here are the URLs for the three webrevs:
http://cr.openjdk.java.net/~dcubed/7182152-webrev/0-hsx23.6/
http://cr.openjdk.java.net/~dcubed/7182152-webrev/0-hsx24/
http://cr.openjdk.java.net/~dcubed/7182152-webrev/0-hsx25/
I have run the following test suites from the JPDA stack on the
JDK7u10/HSX-23.6 version of the fix with
-XX:TraceRedefineClasses=16384
specified:
sdk-jdi
sdk-jdi_closed
sdk-jli
vm-heapdump
vm-hprof
vm-jdb
vm-jdi
vm-jdwp
vm-jvmti
vm-sajdi
The tested configs are:
{Solaris-X86, WinXP}
X {Client VM, Server VM}
X {-Xmixed, -Xcomp}
X {product, fastdebug}
With the 1-liner fix in place, the new tracing code does not
find any
instances of this failure mode in any of the above test suites.
Without
the the 1-liner fix in place, the new tracing code finds one
instance
of this failure mode in the above test suites:
test/java/lang/instrument/IsModifiableClassAgent.java
There are two new tests that will be pushed to the JDK repos using
a different bug ID (not yet filed):
test/com/sun/jdi/RedefineAbstractClass.sh
test/java/lang/instrument/RedefineSubclassWithTwoInterfaces.sh
There will be a separate review request for the new tests.
I'm currently running the JPDA stack of tests on the JDK7u14/HSX-24
and JDK8-B75/HSX-25 versions of the fix. That testing will likely
take all weekend to complete.
Thanks, in advance, for any comments and/or suggestions.
Dan
