Hi Neil,

There is still an issue. Apparently, you can NOT free the buffer for the environment variable.

678                 char * pbuf = (char*)JLI_MemAlloc(pbuflen);
 679                 JLI_Snprintf(pbuf, pbuflen, "%s%d=%s", NMT_Env_Name, 
JLI_GetPid(), value);
 680                 retval = JLI_PutEnv(pbuf);
 681                 if (JLI_IsTraceLauncher()) {
 682                     char* envName;
 683                     char* envBuf;
 684
 685                     // ensures that malloc successful
 686                     envName = (char*)JLI_MemAlloc(pbuflen);
 687                     JLI_Snprintf(envName, pbuflen, "%s%d", NMT_Env_Name, 
JLI_GetPid());
 688
 689                     printf("TRACER_MARKER: NativeMemoryTracking: env var is 
%s\n",envName);
 690                     printf("TRACER_MARKER: NativeMemoryTracking: putenv arg 
%s\n",pbuf);
 691                     envBuf = getenv(envName);
 692                     printf("TRACER_MARKER: NativeMemoryTracking: got value 
%s\n",envBuf);
 693                     free(envName);
 694                 }
 695
 696                 free(pbuf);    <<<<=== can not free this buffer
 697             }


You can experiment it move #696 to #681, you will see the test to fail.

Linux putenv document says:

*putenv*is very widely available, but it might or might not copy its argument, risking memory leaks.


Thanks,

-Zhengyu


On 6/25/2014 4:40 PM, Neil Toda wrote:

Okay, Very glad you checked. It really does need to go as early as your prototype suggested.
I'll get right on it.

-neil

On 6/25/2014 12:05 PM, Zhengyu Gu wrote:
Hi Neil,

I tried out this patch with my hotspot, it does not work.

The reason is that, the environment variable is setup too late, it has to be set before it launches JavaVM (before calling LoadJavaVM()) method.

Thanks,

-Zhengyu

On 6/25/2014 1:58 PM, Neil Toda wrote:
Sorry.  One more webrev .. 06

http://cr.openjdk.java.net/~ntoda/8042469/webrev-06/

Kumar's nit was correct and in fact index was old and should have been removed allowing .contains member to be used instead of .indexOf. So cleaned up a bit more
as can be seen below.  Other of Kumar's nits done.

Thanks Kumar.

webrev-06
  102             // get the PID from the env var we set for the JVM
  103             String envVarPid = null;
  104             for (String line : tr.testOutput) {
  105                 if (line.contains(envVarPidString)) {
  106                     int sindex = envVarPidString.length();
  107                     envVarPid = line.substring(sindex);
  108                     break;
  109                 }
  110             }
  111             // did we find envVarPid?
  112             if (envVarPid == null) {
  113                 System.out.println(tr);
  114                 throw new RuntimeException("Error: failed to find env Var Pid 
in tracking info");
  115             }


webrev-05
  102             // get the PID from the env var we set for the JVM
  103             haveLauncherPid = false;
  104             String envVarPid = null;
  105             for (String line : tr.testOutput) {
  106                 int index;
  107                 if ((index = line.indexOf(envVarPidString)) >= 0) {
  108                     int sindex = envVarPidString.length();
  109                     envVarPid = line.substring(sindex);
  110                     haveLauncherPid = true;
  111                     break;
  112                 }
  113             }
  114             // did we find envVarPid?
  115             if (!haveLauncherPid) {
  116                 System.out.println(tr);
  117                 throw new RuntimeException("Error: failed to find env Var Pid 
in tracking info");
  118             }


On 6/24/2014 2:28 PM, Neil Toda wrote:

New webrev-05 with Kumar's comments except for the "C'ish" style. Explained below.

http://cr.openjdk.java.net/~ntoda/8042469/webrev-05/

105 : DONE
146: DONE
168: DONE

106: Your suggestion was the way I had originally coded it for Linux. However on Windows/Cygwin, the code will not compile There is some interaction with the doExec() preceeding it and the fact that it is a varlist. This coding
         was the simplest workaround.

Thanks for the nits Kumar.


On 6/24/2014 5:36 AM, Kumar Srinivasan wrote:
Neil,

Some nits:

TestSpecialArgs.java:

extra space
105 for ( String line : tr.testOutput) {



This is very C'ish, I suggest.
 -106                 int index;
-107 if ((index = line.indexOf(envVarPidString)) >= 0) {

 +106                 int index = line.indexOf(envVarPidString);
 +107                 if (index >= 0) {


Needs space
-146 launcherPid = line.substring(sindex,tindex);
+146 launcherPid = line.substring(sindex, tindex);

Needs space

-168 if (!tr.contains("NativeMemoryTracking: got value "+NMT_Option_Value)) { +168 if (!tr.contains("NativeMemoryTracking: got value " + NMT_Option_Value)) {


Thanks
Kumar


On 6/23/2014 10:26 AM, Neil Toda wrote:

I've spun a new webrev based on the comments for webrev-03:

http://cr.openjdk.java.net/~ntoda/8042469/webrev-04/

Changes are:

  1) java.c
        a) add free(envName) line 1063
b) change from malloc() to JLI_MemAlloc() @ lines 1048 and 1056

Thanks

-neil

On 6/20/2014 4:45 PM, Kumar Srinivasan wrote:
Neil,

Generally looks good, yes JLI_* functions must be used, I missed that one.
Are you going to post another iteration ?

Kumar

On 6/20/2014 4:27 PM, Neil Toda wrote:

Thanks Joe.  It would have checked for NULL for me.
I'll use the JLI wrapper.

-neil

On 6/20/2014 4:04 PM, Joe Darcy wrote:
Memory allocation in the launcher should use one of the JLI_MemAlloc wrappers, if possible.

-Joe


On 06/20/2014 09:50 AM, Neil Toda wrote:

They should complain. Thanks Zhengyu. I'll make sure these are non-null.

-neil

On 6/20/2014 5:01 AM, Zhengyu Gu wrote:
Neil,

Thanks for quick implementation.

java.c:
Did not check return values of malloc(), I wonder if source code analyzers will complain.

-Zhengyu

On 6/19/2014 8:29 PM, Neil Toda wrote:

Launcher support for modified Native Memory Tracking mechanism in JVM in JDK9.

Webrev  : http://cr.openjdk.java.net/~ntoda/8042469/webrev-03/
bug         : https://bugs.openjdk.java.net/browse/JDK-8042469
CCC         : http://ccc.us.oracle.com/8042469

Thanks.

-neil















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