gnoi-shutdown: use per-thread DB connections to avoid crossed DPU reads#408
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gnoi-shutdown: use per-thread DB connections to avoid crossed DPU reads#408gpunathilell wants to merge 2 commits into
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Signed-off-by: gpunathilell <gpunathilell@nvidia.com>
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| # single non-thread-safe socket, so sharing one lets | ||
| # concurrent DPU reads cross their IP/port values. | ||
| thread_config_db = daemon_base.db_connect("CONFIG_DB") | ||
| thread_state_db = daemon_base.db_connect("STATE_DB") |
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nit (optional, non-blocking): each DPU shutdown opens two fresh redis connections here that live only for this transition. swsscommon.DBConnector has no explicit close()/disconnect(), so they're reclaimed only when
handle_and_cleanup() returns and these locals go out of scope. That's fine given how infrequently DPUs shut down(≤8 per chassis), but good to fix this issue. Otherwise the PR looks good to me
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What I did
gnoi-shutdown-daemonspawns one worker thread per DPU on shutdown, but all threads shared a single CONFIG_DB/STATE_DB redis connection created once inmain(). A redisDBConnectoris a single, non-thread-safe socket, so when multiple DPUs shut down in parallel theirhget/Tablereads interleave on the wire and replies get matched to the wrong request — producing crossed IP/port values between DPUs.This gave gnoi_client a bad target like
169.254.200.1:169.254.200.2(dpu0's IP as host, dpu1's IP in the port slot), causing:Fix
Give each per-DPU worker thread its own CONFIG_DB/STATE_DB connection so reads can never cross:
handle_and_cleanup()opens freshdb_connect("CONFIG_DB")/db_connect("STATE_DB")per thread and passes them into_handle_transition()._handle_transition()/_wait_for_gnoi_halt_in_progress()take optional per-thread connections, falling back to the shared ones for direct/unit-test callers (backward compatible).Testing
py_compileclean.169.254.200.2:50052), and fallback-to-shared preserves existing unit-test behavior.