[jdk11u-dev] Integrated: 8239785: Cgroups: Incorrect detection logic on old systems in hotspot

[Jonathan Dowland]

On Fri, 25 Mar 2022 10:17:45 GMT, Jonathan Dowland <jdowland at openjdk.org> wrote:

> This is a backport of 8239785 for jdk11u. The dependent backports have now all been integrated.
> 
> This PR replaces #881 which was stuck with a dependency on a superseded dependent PR.
> 
> It's not clean, but the only conflict was the copyright line in the
> comment header for src/hotspot/share/prims/whitebox.hpp.
> 
> I'm checking jtreg tests in test/hotspot/jtreg/containers on a mixture of cgroup v1 and v2 systems now.
> 
> ---------
> ### Progress
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This pull request has now been integrated.

Changeset: d5ae8cf0
Author:    Jonathan Dowland <jdowland at openjdk.org>
Committer: Severin Gehwolf <sgehwolf at openjdk.org>
URL:       https://git.openjdk.java.net/jdk11u-dev/commit/d5ae8cf004c4f50d552144a7ac0d933d89d53a75
Stats:     695 lines in 6 files changed: 526 ins; 96 del; 73 mod

8239785: Cgroups: Incorrect detection logic on old systems in hotspot

Return NULL subsystem if no cgroup controllers are mounted.

Reviewed-by: sgehwolf
Backport-of: add18914fb1294999877b563c734a25b4c17b922

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PR: https://git.openjdk.java.net/jdk11u-dev/pull/946