context: fix race between CancellableContext and cancel #5981
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The `pendingDeadline` variable is modified from the ctor of CancellableContext, but it isn't final. The cancellation can happen before the variable is assigned. It's generally bad practice to leak the this reference from the ctor to other threads anyways. This code refactors the deadline calculation and scheduling so that `pendingDeadline` is modified under the lock, and the `this` reference is not exposed. Discovered by TSAN.
carl-mastrangelo
changed the title
ejona86
approved these changes
Jul 16, 2019
zhangkun83
approved these changes
Jul 17, 2019
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The
pendingDeadlinevariable is modified from the ctor of CancellableContext, but it isn't final. The cancellation can happen before the variable is assigned. It's generally bad practice to leak the this reference from the ctor to other threads anyways.This code refactors the deadline calculation and scheduling so that
pendingDeadlineis modified under the lock, and thethisreference is not exposed.Discovered by TSAN.