Wallets search pending deadlock #2983
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This avoids a dependency inversion as node::receive_confirmed searches all wallets. wallet::search_pending we already know the wallet responsible for receiving that block.
wezrule
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Sep 25, 2020
wezrule
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Sep 25, 2020
guilhermelawless
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Sep 28, 2020
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Only an issue in develop. Two different paths can deadlock:
node::search_pending -> wallets::search_pending_all -> wallets mutex lock -> wallet::search_pending -> node::receive_confirmed -> wallets mutex lockRPC -> wallets::search_pending -> wallets mutex lock -> wallet::search_pending -> node::receive_confirmed -> wallets mutex lockThis fixes the deadlock by unlocking the wallets mutex before calling
wallet::search_pending, as there is no need to hold it. But also notes that callingnode::receive_confirmedfrom the wallet is a dependency inversion. There's no need to search for the wallet again and we are sure the block exists, soreceive_asynccan be directly called.@SergiySW note this means pruning #2881 (I don't think this part has been split yet) will have to consider this new case in
wallet::search_pending, not only innode::receive_confirmed.The added unit test is identical to the existing wallet.search_pending but is now done for wallets