20 lines
603 B
Plaintext
20 lines
603 B
Plaintext
== Why is this an issue?
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When two locks are held simultaneously, a ``++wait++`` call only releases one of them. The other will be held until some other thread requests a lock on the awaited object.
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If no unrelated code tries to lock on that object, then all other threads will be locked out, resulting in a deadlock.
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=== Noncompliant code example
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[source,text]
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----
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synchronized (this.mon1) { // threadB can't enter this block to request this.mon2 lock & release threadA
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synchronized (this.mon2) {
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this.mon2.wait(); // Noncompliant; threadA is stuck here holding lock on this.mon1
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}
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}
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----
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