From sroy at openjdk.org  Wed Aug  6 13:43:17 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Wed, 6 Aug 2025 13:43:17 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v3]
In-Reply-To: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
Message-ID: <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>

> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
> 
> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
> 
> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
> 
> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
> 
> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
> 
> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all

Suchismith Roy has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains eight commits:

 - Merge branch 'master' into cpuprocessload
 - Merge branch 'master' into cpuprocessload
 - Update UnixOperatingSystem.c
 - Merge branch 'openjdk:master' into cpuprocessload
 - cleanup
 - system cpu load
 -  restore problem list
 - cpu process load

-------------

Changes: https://git.openjdk.org/jdk/pull/25332/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=02
  Stats: 79 lines in 2 files changed: 73 ins; 2 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/25332.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25332/head:pull/25332

PR: https://git.openjdk.org/jdk/pull/25332

From mbaesken at openjdk.org  Wed Aug  6 13:51:04 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Wed, 6 Aug 2025 13:51:04 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v3]
In-Reply-To: <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>
Message-ID: <vhGIQaSa5NVpATx4FZLCVkC6UbRZrWOyTydhV4r67bE=.0faae477-b911-4749-96d5-556d1aa91276@github.com>

On Wed, 6 Aug 2025 13:43:17 GMT, Suchismith Roy <sroy at openjdk.org> wrote:

>> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
>> 
>> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
>> 
>> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
>> 
>> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
>> 
>> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
>> 
>> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
>> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all
>
> Suchismith Roy has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains eight commits:
> 
>  - Merge branch 'master' into cpuprocessload
>  - Merge branch 'master' into cpuprocessload
>  - Update UnixOperatingSystem.c
>  - Merge branch 'openjdk:master' into cpuprocessload
>  - cleanup
>  - system cpu load
>  -  restore problem list
>  - cpu process load

test/jdk/ProblemList.txt line 558:

> 556: 
> 557: 
> 558: com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java     8364314 generic-all

Wondering - why is that added ? Is it intended ?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2257230418

From sroy at openjdk.org  Wed Aug  6 14:13:05 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Wed, 6 Aug 2025 14:13:05 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v3]
In-Reply-To: <vhGIQaSa5NVpATx4FZLCVkC6UbRZrWOyTydhV4r67bE=.0faae477-b911-4749-96d5-556d1aa91276@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>
 <vhGIQaSa5NVpATx4FZLCVkC6UbRZrWOyTydhV4r67bE=.0faae477-b911-4749-96d5-556d1aa91276@github.com>
Message-ID: <3Vwjg-ioaRzQHhcP2VoZTnDl9SSLk2BLlsoJ22Gia44=.5222663d-8705-47cc-a060-2b57f92f119a@github.com>

On Wed, 6 Aug 2025 13:48:15 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> Suchismith Roy has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains eight commits:
>> 
>>  - Merge branch 'master' into cpuprocessload
>>  - Merge branch 'master' into cpuprocessload
>>  - Update UnixOperatingSystem.c
>>  - Merge branch 'openjdk:master' into cpuprocessload
>>  - cleanup
>>  - system cpu load
>>  -  restore problem list
>>  - cpu process load
>
> test/jdk/ProblemList.txt line 558:
> 
>> 556: 
>> 557: 
>> 558: com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java     8364314 generic-all
> 
> Wondering - why is that added ? Is it intended ?

@MBaesken it was part of master branch. shall I remove it ?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2257317031

From mbaesken at openjdk.org  Wed Aug  6 14:17:04 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Wed, 6 Aug 2025 14:17:04 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v3]
In-Reply-To: <3Vwjg-ioaRzQHhcP2VoZTnDl9SSLk2BLlsoJ22Gia44=.5222663d-8705-47cc-a060-2b57f92f119a@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>
 <vhGIQaSa5NVpATx4FZLCVkC6UbRZrWOyTydhV4r67bE=.0faae477-b911-4749-96d5-556d1aa91276@github.com>
 <3Vwjg-ioaRzQHhcP2VoZTnDl9SSLk2BLlsoJ22Gia44=.5222663d-8705-47cc-a060-2b57f92f119a@github.com>
Message-ID: <t9JTli2Hboqs_ee-wUgti4h-Z5ofL2XjogYAmkr8FPs=.eb1845c7-e743-49a0-8002-82ab7d63bb50@github.com>

On Wed, 6 Aug 2025 14:10:44 GMT, Suchismith Roy <sroy at openjdk.org> wrote:

>> test/jdk/ProblemList.txt line 558:
>> 
>>> 556: 
>>> 557: 
>>> 558: com/sun/management/HotSpotDiagnosticMXBean/DumpThreads.java     8364314 generic-all
>> 
>> Wondering - why is that added ? Is it intended ?
>
> @MBaesken it was part of master branch. shall I remove it ?

Did not expect this in your PR .
Bit unsure why it is there.

It is not here https://github.com/openjdk/jdk/blob/master/test/jdk/ProblemList.txt  so  why is it needed in your PR ?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2257330020

From sroy at openjdk.org  Wed Aug  6 15:08:18 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Wed, 6 Aug 2025 15:08:18 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v3]
In-Reply-To: <t9JTli2Hboqs_ee-wUgti4h-Z5ofL2XjogYAmkr8FPs=.eb1845c7-e743-49a0-8002-82ab7d63bb50@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <MwNZYWo3EJqcvO8_Zw2NI1xpXw0i4gQZaA1RIqkY_1I=.c4101671-23d0-4d05-9b7e-2aed20c766b5@github.com>
 <vhGIQaSa5NVpATx4FZLCVkC6UbRZrWOyTydhV4r67bE=.0faae477-b911-4749-96d5-556d1aa91276@github.com>
 <3Vwjg-ioaRzQHhcP2VoZTnDl9SSLk2BLlsoJ22Gia44=.5222663d-8705-47cc-a060-2b57f92f119a@github.com>
 <t9JTli2Hboqs_ee-wUgti4h-Z5ofL2XjogYAmkr8FPs=.eb1845c7-e743-49a0-8002-82ab7d63bb50@github.com>
Message-ID: <z6jl1VCywh4C1W_6JPu9leQ5WuTgOK5koOWggNP0jSA=.f308ab3c-b480-45cd-98ca-42abe4fb7398@github.com>

On Wed, 6 Aug 2025 14:14:53 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> @MBaesken it was part of master branch. shall I remove it ?
>
> Did not expect this in your PR .
> Bit unsure why it is there.
> 
> It is not here https://github.com/openjdk/jdk/blob/master/test/jdk/ProblemList.txt  so  why is it needed in your PR ?

@MBaesken  Not sure. It was showing as a conflict due a change from master, so I thought to keep it. Will remove it then.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2257492886

From sroy at openjdk.org  Wed Aug  6 15:08:18 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Wed, 6 Aug 2025 15:08:18 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v4]
In-Reply-To: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
Message-ID: <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>

> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
> 
> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
> 
> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
> 
> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
> 
> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
> 
> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all

Suchismith Roy has updated the pull request incrementally with one additional commit since the last revision:

  Update ProblemList.txt

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/25332/files
  - new: https://git.openjdk.org/jdk/pull/25332/files/80a6dba6..e4c076f7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=02-03

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/25332.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25332/head:pull/25332

PR: https://git.openjdk.org/jdk/pull/25332

From stuefe at openjdk.org  Thu Aug  7 05:39:17 2025
From: stuefe at openjdk.org (Thomas Stuefe)
Date: Thu, 7 Aug 2025 05:39:17 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v4]
In-Reply-To: <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
Message-ID: <sHCvgmsnNbRTcLaUCuQctBVWoDhr8RvBgedviW4J_pE=.9cd3d230-bb34-439e-b5ec-65eddb043be2@github.com>

On Wed, 6 Aug 2025 15:08:18 GMT, Suchismith Roy <sroy at openjdk.org> wrote:

>> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
>> 
>> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
>> 
>> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
>> 
>> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
>> 
>> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
>> 
>> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
>> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all
>
> Suchismith Roy has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update ProblemList.txt

> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
> 

Who? me? Other Reviewers? Strange PR description ;-)

-------------

PR Comment: https://git.openjdk.org/jdk/pull/25332#issuecomment-3162562129

From stuefe at openjdk.org  Thu Aug  7 06:06:17 2025
From: stuefe at openjdk.org (Thomas Stuefe)
Date: Thu, 7 Aug 2025 06:06:17 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v4]
In-Reply-To: <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
Message-ID: <k6YJ-kXZ1Gb37iQiFmuHUvtizBUid7aJYomT1TqL5Gs=.f562f73e-e3d1-447f-a9e3-09ac9cf5a1e4@github.com>

On Wed, 6 Aug 2025 15:08:18 GMT, Suchismith Roy <sroy at openjdk.org> wrote:

>> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
>> 
>> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
>> 
>> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
>> 
>> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
>> 
>> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
>> 
>> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
>> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all
>
> Suchismith Roy has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update ProblemList.txt

Changes requested by stuefe (Reviewer).

src/jdk.management/aix/native/libmanagement_ext/UnixOperatingSystem.c line 43:

> 41: static perfstat_cpu_total_t cpu_total_old;
> 42: static time_t last_sample_time = 0;
> 43: static double last_cpu_load = -1.0;

Not threadsafe. What happens if you call this concurrently from multiple threads? Visibility of these three values can be in any order of updates. You'd get skewed values.

Check out how Linux does it. They use mutexes to synchronize access to this function.

src/jdk.management/aix/native/libmanagement_ext/UnixOperatingSystem.c line 54:

> 52:     if (initialized && (now - last_sample_time < 5)) {
> 53:         return last_cpu_load; // Return cached value if less than 5s
> 54:     }

Are you sure this is needed? How slow is perfstat_cpu_total?

src/jdk.management/aix/native/libmanagement_ext/UnixOperatingSystem.c line 102:

> 100:         prev_timebase = curr_stats.last_timebase;
> 101:         initialized = 1;
> 102:         return -1.0;

Here, and above in the other function: this seems wrong and would result in the first measurement to be off (or very large if displayed as unsigned).

See how Linux does it in perfInit().

-------------

PR Review: https://git.openjdk.org/jdk/pull/25332#pullrequestreview-3095405436
PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2259126398
PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2259127887
PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2259157137

From stuefe at openjdk.org  Thu Aug  7 06:06:18 2025
From: stuefe at openjdk.org (Thomas Stuefe)
Date: Thu, 7 Aug 2025 06:06:18 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v4]
In-Reply-To: <k6YJ-kXZ1Gb37iQiFmuHUvtizBUid7aJYomT1TqL5Gs=.f562f73e-e3d1-447f-a9e3-09ac9cf5a1e4@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
 <k6YJ-kXZ1Gb37iQiFmuHUvtizBUid7aJYomT1TqL5Gs=.f562f73e-e3d1-447f-a9e3-09ac9cf5a1e4@github.com>
Message-ID: <9IAX8fOEqLRoOeFdOR1lNTcFTtlipeXO5as2BFahcpg=.b40d3fac-17cd-4f0d-ad6c-5c59902042a4@github.com>

On Thu, 7 Aug 2025 05:46:29 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> Suchismith Roy has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Update ProblemList.txt
>
> src/jdk.management/aix/native/libmanagement_ext/UnixOperatingSystem.c line 43:
> 
>> 41: static perfstat_cpu_total_t cpu_total_old;
>> 42: static time_t last_sample_time = 0;
>> 43: static double last_cpu_load = -1.0;
> 
> Not threadsafe. What happens if you call this concurrently from multiple threads? Visibility of these three values can be in any order of updates. You'd get skewed values.
> 
> Check out how Linux does it. They use mutexes to synchronize access to this function.

Style nit, you may want to group these together into a nice structure, too.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2259142734

From duke at openjdk.org  Fri Aug  8 13:09:42 2025
From: duke at openjdk.org (Lei Zhu)
Date: Fri, 8 Aug 2025 13:09:42 GMT
Subject: jmx-dev RFR: 8362533: Tests
 sun/management/jmxremote/bootstrap/* duplicate VM flags [v2]
In-Reply-To: <sfMcesDrfgGXonjkPPs5aHMF1FW0Cac0kkvgRC0HjOY=.227e3d2a-ac8a-448c-abe2-8d763be97b18@github.com>
References: <hokO-PHPwP02HfNEz1i6M97mIDwk2j0A7V381Ou7kic=.cf075bd0-7ca6-4523-98f6-d89c57d5f1d2@github.com>
 <0XgKkckS1Dk_jyA5ojiQzdopsrs-O5KLu__l7xsQV3g=.da19026b-55a6-4972-9e65-0f712b98ac99@github.com>
 <sfMcesDrfgGXonjkPPs5aHMF1FW0Cac0kkvgRC0HjOY=.227e3d2a-ac8a-448c-abe2-8d763be97b18@github.com>
Message-ID: <GqmYCd06B_cojldt6bt9isNfoQHirII6d8VxYjDfKNU=.59e17f5c-273d-4499-8184-3b6bd13298e9@github.com>

On Thu, 31 Jul 2025 13:11:13 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

>> Lei Zhu has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   remove duplicate -cp
>
> Looks good.
> (More than trivial, but good. 8-) )

@kevinjwalls Thanks!

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26555#issuecomment-3148349512

From sroy at openjdk.org  Mon Aug 25 09:30:56 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Mon, 25 Aug 2025 09:30:56 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v4]
In-Reply-To: <k6YJ-kXZ1Gb37iQiFmuHUvtizBUid7aJYomT1TqL5Gs=.f562f73e-e3d1-447f-a9e3-09ac9cf5a1e4@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
 <_h4TBkuFudR5wTGue1oEaeqlZcPZfPnJcWmFdWboZfM=.5676751b-ad3b-4b37-9822-b17464c093dc@github.com>
 <k6YJ-kXZ1Gb37iQiFmuHUvtizBUid7aJYomT1TqL5Gs=.f562f73e-e3d1-447f-a9e3-09ac9cf5a1e4@github.com>
Message-ID: <pirpK_avi2C6QJi2mqtu4zUiFZ7EJQ4cBwivhmIoG-Q=.d4e8028d-85f6-4b9d-939c-479b3e12d316@github.com>

On Thu, 7 Aug 2025 06:01:12 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> Suchismith Roy has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Update ProblemList.txt
>
> src/jdk.management/aix/native/libmanagement_ext/UnixOperatingSystem.c line 102:
> 
>> 100:         prev_timebase = curr_stats.last_timebase;
>> 101:         initialized = 1;
>> 102:         return -1.0;
> 
> Here, and above in the other function: this seems wrong and would result in the first measurement to be off (or very large if displayed as unsigned).
> 
> See how Linux does it in perfInit().

@tstuefe  You mean the first load calculated would be -1 and that would be an issue ? or is it about finding the right delta between measurements ?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/25332#discussion_r2297589566

From mbaesken at openjdk.org  Wed Aug 27 14:30:19 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Wed, 27 Aug 2025 14:30:19 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer] UnixOperatingSystem.c
 warning: use of uninitialized value 'systemTicks'
Message-ID: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>

When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :

/jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
/jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
  208 | pticks->usedKernel = systemTicks;


vsscanf usually/normally reads the systemTicks info from /proc file system. see
https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
but we never check that the *exact* number of params is read with vsscanf :
n = vsscanf(tmp, fmt, args);
So potentially we could get a non complete info without systemTicks and the call would still succeed.

-------------

Commit messages:
 - JDK-8366092

Changes: https://git.openjdk.org/jdk/pull/26962/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26962&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8366092
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26962.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26962/head:pull/26962

PR: https://git.openjdk.org/jdk/pull/26962

From mbaesken at openjdk.org  Wed Aug 27 14:39:01 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Wed, 27 Aug 2025 14:39:01 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
Message-ID: <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>

> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
> 
> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>   208 | pticks->usedKernel = systemTicks;
> 
> 
> vsscanf usually/normally reads the systemTicks info from /proc file system. see
> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
> but we never check that the *exact* number of params is read with vsscanf :
> n = vsscanf(tmp, fmt, args);
> So potentially we could get a non complete info without systemTicks and the call would still succeed.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  init vars so that gcc static analyzer is happy too

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/26962/files
  - new: https://git.openjdk.org/jdk/pull/26962/files/1e9f0572..cb0f8dfc

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26962&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26962&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26962.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26962/head:pull/26962

PR: https://git.openjdk.org/jdk/pull/26962

From kevinw at openjdk.org  Wed Aug 27 17:46:41 2025
From: kevinw at openjdk.org (Kevin Walls)
Date: Wed, 27 Aug 2025 17:46:41 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
Message-ID: <_dzoj_TlgAVspeaYaN5Vaflby5PlodGQ4n3gPXUWIVg=.6933935b-3db2-4430-a5a0-cc44f733dc2b@github.com>

On Wed, 27 Aug 2025 14:39:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   init vars so that gcc static analyzer is happy too

Yes, seems we have two almost identical read_ticks functions, that's not ideal but hotspot and libmanagement both needed it... Maybe that can be deduplicated in future. 8-)


If we now return when read_ticks doesn't read and set both variables, then the "use of uninitialized value" warning becomes incorrect.

And with the !=2 check it becomes the same as the other usage, in src/hotspot/os/linux/os_perf_linux.cpp

 313 static OSReturn get_jvm_ticks(os::Linux::CPUPerfTicks* pticks) {
 314   uint64_t userTicks;
 315   uint64_t systemTicks;
...
 321   if (read_ticks("/proc/self/stat", &userTicks, &systemTicks) != 2) {
 322     return OS_ERR;
 323   }

...so does that other code have the same analyzer warning?

Ideally I expect we would not change the code just to keep a tool happy, if the warning is not really accurate.... (and presumably the warning might get more accurate in future)

-------------

PR Review: https://git.openjdk.org/jdk/pull/26962#pullrequestreview-3161078387

From mbaesken at openjdk.org  Thu Aug 28 12:00:44 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Thu, 28 Aug 2025 12:00:44 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <_dzoj_TlgAVspeaYaN5Vaflby5PlodGQ4n3gPXUWIVg=.6933935b-3db2-4430-a5a0-cc44f733dc2b@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
 <_dzoj_TlgAVspeaYaN5Vaflby5PlodGQ4n3gPXUWIVg=.6933935b-3db2-4430-a5a0-cc44f733dc2b@github.com>
Message-ID: <U4PBYZk4xiJVr97NKumH2Ablv1mxEJs32zrc0bjm2qU=.d706ee8d-3ec1-434e-a334-3703b9432a68@github.com>

On Wed, 27 Aug 2025 17:44:02 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

> so does that other code have the same analyzer warning?

The other one from os_perf_linux.cpp  is Hotspot/C++ code and the gcc static analyzer does not work well with C++ (see https://gcc.gnu.org/bugzilla/showdependencytree.cgi?id=97110 ).  In the future it  will most likely support C++ too.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3233198601

From mbaesken at openjdk.org  Thu Aug 28 12:00:46 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Thu, 28 Aug 2025 12:00:46 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
Message-ID: <f7jd1xPSJsOEav1MF6fVGmaCiSFyzJmw2tBdR2tq4OE=.ea5dec14-c763-4261-9ef6-07a847db467b@github.com>

On Wed, 27 Aug 2025 14:39:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   init vars so that gcc static analyzer is happy too

I think initializing the vars is a good practise.  And checking for `!= 2`  as you suggested makes sense and should be done here (as we do  in Hotspot).

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3233205380

From sroy at openjdk.org  Fri Aug 29 08:50:37 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Fri, 29 Aug 2025 08:50:37 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v5]
In-Reply-To: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
Message-ID: <D2iufQhiyPLZCotKssNteiNXs_X1wzP4MlL3DZLy0N8=.5e310421-11e7-4db2-ad7d-580044c2402c@github.com>

> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
> 
> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
> 
> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
> 
> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
> 
> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
> 
> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all

Suchismith Roy has updated the pull request incrementally with two additional commits since the last revision:

 - Thread safety,struct and perfInit()
 - Thread safety,struct and perfInit()

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/25332/files
  - new: https://git.openjdk.org/jdk/pull/25332/files/e4c076f7..e064140b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=03-04

  Stats: 121 lines in 1 file changed: 62 ins; 40 del; 19 mod
  Patch: https://git.openjdk.org/jdk/pull/25332.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25332/head:pull/25332

PR: https://git.openjdk.org/jdk/pull/25332

From sroy at openjdk.org  Fri Aug 29 08:56:56 2025
From: sroy at openjdk.org (Suchismith Roy)
Date: Fri, 29 Aug 2025 08:56:56 GMT
Subject: jmx-dev RFR: JDK-8030957 - AIX: Implement
 OperatingSystemMXBean.getSystemCpuLoad() and .getProcessCpuLoad() on AIX
 [v6]
In-Reply-To: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
References: <yXCvgLfqR6njrThw64aiG0NOmEjQBxy44ihOj9eq2O0=.15d50acd-a7f5-4a25-9c97-1d68e2267f57@github.com>
Message-ID: <sNkjTIdB4hhRCT7pzNZc6-5YYPbujw4UPPS5BOnKIyQ=.53da5534-6479-4dc7-9997-3ed38f097fd8@github.com>

> JBS Issue : [JDK-8030957](https://bugs.openjdk.org/browse/JDK-8030957)
> 
> These two methods should be implemented in src/aix/native/sun/management/AixOperatingSystem.c (which has to be created).
> 
> getProcessCpuLoad() can be probably implemented in the same way like on Solaris be reading /proc/self/psinfo
> 
> For getSystemCpuLoad() we'll probalby have to use 'perfstat_cpu_total()' from libperf (see http://publib.boulder.ibm.com/infocenter/pseries/v5r3/topic/com.ibm.aix.prftools/doc/prftools/prftools07.htm#wq407)
> 
> Once this issue has been resolved you should not forget to remove the two excludes from jdk/test/ProblemList.txt:
> 
> com/sun/management/OperatingSystemMXBean/GetProcessCpuLoad.java aix-all
> com/sun/management/OperatingSystemMXBean/GetSystemCpuLoad.java aix-all

Suchismith Roy has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 12 commits:

 - Merge branch 'openjdk:master' into cpuprocessload
 - Thread safety,struct and perfInit()
 - Thread safety,struct and perfInit()
 - Update ProblemList.txt
 - Merge branch 'master' into cpuprocessload
 - Merge branch 'master' into cpuprocessload
 - Update UnixOperatingSystem.c
 - Merge branch 'openjdk:master' into cpuprocessload
 - cleanup
 - system cpu load
 - ... and 2 more: https://git.openjdk.org/jdk/compare/86d6a2e0...46dcf313

-------------

Changes: https://git.openjdk.org/jdk/pull/25332/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25332&range=05
  Stats: 100 lines in 2 files changed: 94 ins; 2 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/25332.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25332/head:pull/25332

PR: https://git.openjdk.org/jdk/pull/25332

From kevinw at openjdk.org  Fri Aug 29 10:22:48 2025
From: kevinw at openjdk.org (Kevin Walls)
Date: Fri, 29 Aug 2025 10:22:48 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
Message-ID: <Y8RlAnI4cnoVsUFLxIF-zheY9imYZ0ByobcJmPh-W3I=.3ab4f221-04c1-43f8-a654-4ccb3edb6325@github.com>

On Wed, 27 Aug 2025 14:39:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   init vars so that gcc static analyzer is happy too

Assigning zero to values we are about to set with vsscanf, or are going to ignore, is being added here to keep the analyzer happy.    I think we should not do this, and leave the initialization to scanf.  (Unless there is some case where it creates a problem.)

The extra initialization looks harmless, and while not hugely wasteful, if we do this one, then it starts a long path of adding extra initialization as we have various other examples.

"src/hotspot/os/linux/os_perf_linux.cpp" as discussed has the same.

Back in 
"src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c"

get_totalticks:

 87 static int get_totalticks(int which, ticks *pticks) {
...
 89     uint64_t        userTicks, niceTicks, systemTicks, idleTicks;
 90     uint64_t        iowTicks = 0, irqTicks = 0, sirqTicks= 0;
...
 97     n = fscanf(fh, "cpu " DEC_64 " " DEC_64 " " DEC_64 " " DEC_64 " " DEC_64 " "
 98                    DEC_64 " " DEC_64,
 99            &userTicks, &niceTicks, &systemTicks, &idleTicks,
100            &iowTicks, &irqTicks, &sirqTicks);


This one does not initialize userTicks and 3 others, but does initialize iowTicks and others.
We check fscanf result < 4 to mean an error, it failed to read the essential values (that we don't manually initialize).

Other examples include src/java.base/unix/native/jspawnhelper/jspawnhelper.c
where local int variables are initialized only by a call to scanf, or otherwise ignored.

(There are examples where we do initialize such a local int, but that doesn't mean it's necessary.)

I'd recommend we don't start initializing things that we can see are either initialized slightly later, or are ignored.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3236525852

From mbaesken at openjdk.org  Fri Aug 29 14:11:01 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Fri, 29 Aug 2025 14:11:01 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v3]
In-Reply-To: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
Message-ID: <mFCocD24ZlodX8iS45JnH_8H2-RLYBTPOFTu-OyCTYU=.c7641333-d14c-44f8-bb68-4c796c619dc8@github.com>

> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
> 
> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>   208 | pticks->usedKernel = systemTicks;
> 
> 
> vsscanf usually/normally reads the systemTicks info from /proc file system. see
> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
> but we never check that the *exact* number of params is read with vsscanf :
> n = vsscanf(tmp, fmt, args);
> So potentially we could get a non complete info without systemTicks and the call would still succeed.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  Avoid initialization

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/26962/files
  - new: https://git.openjdk.org/jdk/pull/26962/files/cb0f8dfc..daf31fe6

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=26962&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=26962&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/26962.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26962/head:pull/26962

PR: https://git.openjdk.org/jdk/pull/26962

From mbaesken at openjdk.org  Fri Aug 29 14:11:01 2025
From: mbaesken at openjdk.org (Matthias Baesken)
Date: Fri, 29 Aug 2025 14:11:01 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v2]
In-Reply-To: <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <x9qr_uTQsBylJzSEnZUdU1HcNxEPiejXxjIUs_4bSQE=.4c3c2282-02ee-45f9-918a-e12d9f4865c2@github.com>
Message-ID: <OFtJW-g51j8I4naZIL4_769ZSe8oSTggra9EmbiXa-A=.087f6c87-1c4d-4aea-a843-42baa4588e5f@github.com>

On Wed, 27 Aug 2025 14:39:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   init vars so that gcc static analyzer is happy too

Okay then let's avoid the initialization.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3237165958

From kevinw at openjdk.org  Fri Aug 29 14:13:42 2025
From: kevinw at openjdk.org (Kevin Walls)
Date: Fri, 29 Aug 2025 14:13:42 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v3]
In-Reply-To: <mFCocD24ZlodX8iS45JnH_8H2-RLYBTPOFTu-OyCTYU=.c7641333-d14c-44f8-bb68-4c796c619dc8@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <mFCocD24ZlodX8iS45JnH_8H2-RLYBTPOFTu-OyCTYU=.c7641333-d14c-44f8-bb68-4c796c619dc8@github.com>
Message-ID: <ov9FS16cbr4_EmOcZR5CFSfkXizE3KejIyVx6-a2Jjk=.3a6f7475-59b0-4510-9633-5e11ac8540a5@github.com>

On Fri, 29 Aug 2025 14:11:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Avoid initialization

Marked as reviewed by kevinw (Reviewer).

Thanks!

-------------

PR Review: https://git.openjdk.org/jdk/pull/26962#pullrequestreview-3168897601
PR Comment: https://git.openjdk.org/jdk/pull/26962#issuecomment-3237175399

From asteiner at openjdk.org  Fri Aug 29 14:26:13 2025
From: asteiner at openjdk.org (Andreas Steiner)
Date: Fri, 29 Aug 2025 14:26:13 GMT
Subject: jmx-dev RFR: 8366092: [GCC static analyzer]
 UnixOperatingSystem.c warning: use of uninitialized value 'systemTicks'
 [v3]
In-Reply-To: <mFCocD24ZlodX8iS45JnH_8H2-RLYBTPOFTu-OyCTYU=.c7641333-d14c-44f8-bb68-4c796c619dc8@github.com>
References: <Xtuc-XzN9PrfsXTINWSk6WV05ytWN9hz0C7wIFlXNy8=.a00fc7b4-8579-4c26-9198-8c770989fdf9@github.com>
 <mFCocD24ZlodX8iS45JnH_8H2-RLYBTPOFTu-OyCTYU=.c7641333-d14c-44f8-bb68-4c796c619dc8@github.com>
Message-ID: <l4lKnF-II5J5qPXgcArQAj9T4ijAlL0LLa6nybEKeWI=.b3302d1c-7b40-429c-bcaf-27c4caa2676c@github.com>

On Fri, 29 Aug 2025 14:11:01 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

>> When using gcc static analyzer (-fanalyzer) with gcc 13.2 the following issue is reported :
>> 
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c: In function 'get_jvmticks':
>> /jdk/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c:208:24: warning: use of uninitialized value 'systemTicks' [CWE-457] [-Wanalyzer-use-of-uninitialized-value]
>>   208 | pticks->usedKernel = systemTicks;
>> 
>> 
>> vsscanf usually/normally reads the systemTicks info from /proc file system. see
>> https://github.com/openjdk/jdk/blob/45726a1f8b8f76586037867a32b82f8ab9b96937/src/jdk.management/linux/native/libmanagement_ext/UnixOperatingSystem.c#L163
>> but we never check that the *exact* number of params is read with vsscanf :
>> n = vsscanf(tmp, fmt, args);
>> So potentially we could get a non complete info without systemTicks and the call would still succeed.
>
> Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Avoid initialization

Marked as reviewed by asteiner (Author).

-------------

PR Review: https://git.openjdk.org/jdk/pull/26962#pullrequestreview-3168939581