Allow nested rtxn from wtxn #3
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Kerollmops
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Kerollmops
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Kerollmops
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Kerollmops
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Use the correct stack index when adjusting other cursors pointing to the affected page and the DB has a subDB. Broken in ITS#8406.
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| txn->mt_cursors = (MDB_cursor **)(txn->mt_dbs + env->me_maxdbs); | ||
| txn->mt_dbiseqs = parent->mt_dbiseqs; | ||
| /* Not useful when nested RDONLY but correctly freed in mdb_txn_end */ | ||
| txn->mt_u.dirty_list = malloc(sizeof(MDB_ID2)*MDB_IDL_UM_SIZE); |
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We accept nested read-only transactions and no longer count them to accept more than a single one. We make sure that we free/close the child transactions only once the last one has been dropped. We use atomics to implement a reference-counted system to correctly drop the read transactions and the pghead only once. This is not C99 but C11-compatible.
Co-authored-by: dureuil <[email protected]>
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In this PR, we accept nested read-only transactions and no longer count them to accept more than one. We free/close the child transactions only once the last one has been dropped. I am proposing this patch upstream.
We use atomics to implement a reference-counted system that correctly drops the read transactions and the pghead only once. This is not C99 but C11-compatible.
Warning
We found a memory leak in this PR. We need to take time to investigate the matter and fix it.