tree 713a8d23a9d5586abf60ce691c560294ff615c9a
parent d0ecc0870525e94554975f2fef1ceee3cc0c6b4c
author Eric Anderson <ejona@google.com> 1548975465 -0800
committer Eric Anderson <ejona@google.com> 1548980674 -0800

core: Fix racy creation/set of the retry Future

This fixes two races: a data race where scheduledRetry is accessed
by cancel() and confusion where scheduledRetry could be set to null by
the schedule()d runnable before it is set by the schedule() return
value.

Although it seems these races can't actually cause problems due to other
conditions/constraints, it's hard to reason about. So let's plug these
preemptively, even if we can't add tests that trigger them.

ScheduledHedging was not specific to hedging, so can now be reused for
this retry case. It was renamed to avoid being misleading.