Fix race condition in DropInTokio
#4593
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The previous code had a race condition - it was possible that `Arc::get_mut` would return `None` for all threads (if every thread holding a cloned `DropInTokio` executed `drop` simultaneously). This would cause the inner `Client` to not get dropped within the 'in_tokio_runtime_no_gil', leading to a panic when the inner drop tried to use the Tokio runtime
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I'm not sure if this is related to #4326 |
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Aaron1011
November 13, 2025 18:17
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Pull Request Overview
This PR fixes a critical race condition in the DropInTokio implementation where multiple threads dropping cloned instances simultaneously could cause Arc::get_mut to return None for all threads, preventing proper cleanup of the inner Client within the Tokio runtime.
Key changes:
- Replaced
Arc::get_mutwithArc::into_innerto guarantee exactly one thread succeeds in extracting the inner value - Modified the dummy value to be wrapped in an
Arcto work with the newstd::mem::replaceapproach
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#4595 will make this unnecessary, since the relevant logic is entirely removed in that PR |
virajmehta
approved these changes
Nov 14, 2025
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I'm going to merge #4595 instead |
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The previous code had a race condition - it was possible that
Arc::get_mutwould returnNonefor all threads (if every thread holding a clonedDropInTokioexecuteddropsimultaneously). This would cause the innerClientto not get dropped within the 'in_tokio_runtime_no_gil', leading to a panic when the inner drop tried to use the Tokio runtimeImportant
Fixes race condition in
DropInTokio::dropby usingArc::into_innerto ensure proper dropping of innerClient.DropInTokio::dropby usingArc::into_innerinstead ofArc::get_mutto ensure proper dropping of innerClientwithinin_tokio_runtime_no_gil.DropInTokiosimultaneously.Arc::get_mutwithArc::into_innerinDropInTokio::dropingil_helpers.rs.This description was created by
for e8e625c. You can customize this summary. It will automatically update as commits are pushed.