8356233: NMT: tty->print_cr should not be used in VirtualMemoryTracker::add_reserved_region()

[gerard-ziemski]

To help with debugging NMT we added more info when an assert gets triggered, but we used tty, which is involved with locks and unfortunately it triggered:

# Internal Error (.../open/src/hotspot/share/runtime/mutex.cpp:457), pid=1088443, tid=1088520
# assert(false) failed: Attempting to acquire lock tty_lock/tty out of order with lock NmtVirtualMemory_lock/service-4 -- possible deadlock

We avoid this, by printing using UL instead of using tty directly.

---

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Issue

• JDK-8356233: NMT: tty->print_cr should not be used in VirtualMemoryTracker::add_reserved_region() (Bug - P4)

Reviewers

• Johan Sjölen (@jdksjolen - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)

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[openjdk]

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8356233: NMT: tty->print_cr should not be used in VirtualMemoryTracker::add_reserved_region()

Reviewed-by: jsjolen, dholmes

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• 02: Full - Incremental (5b0e0f58)
• 01: Full - Incremental (985856ec)
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[dholmes-ora]

Overall conversion looks good. If there is no chance of UL using NMT in a way that leads to VMT then this is fine.

Please fix the tag->unsigned->tag code.

Thanks

[gerard-ziemski]

Thank you Johan and David for your feedback!

[dholmes-ora]

LGTM.

Thanks

[jdksjolen]

LGTM

[gerard-ziemski]

/integrate

[openjdk]

Going to push as commit 28f5093.
Since your change was applied there have been 9 commits pushed to the master branch:

• cd052c7: 8345431: Improve jar --validate to detect duplicate or invalid entries
• b2a61a9: 8356985: Use "stdin.encoding" in Console's read*() methods
• 8949c07: 8357930: Amendment for JDK-8333664
• ... and 6 more: https://git.openjdk.org/jdk/compare/7bd8375fe49eedecae7b2a1c75e7efb5ab06b22d...master

Your commit was automatically rebased without conflicts.

[openjdk]

@gerard-ziemski Pushed as commit 28f5093.

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