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PG-1349 Fix deadlock

PG-1349-deadlock
Artem Gavrilov 2025-02-18 12:31:24 +02:00
parent fd43b75153
commit ec1d449dc5
1 changed files with 113 additions and 91 deletions
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36
pg_stat_monitor.c
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@ -1968,6 +1968,10 @@ pgsm_store(pgsmEntry *entry)
* we need to create the entry.
*/
LWLockAcquire(pgsm->lock, LW_SHARED);
PG_TRY();
{
shared_hash_entry = (pgsmEntry *) pgsm_hash_find(get_pgsmHash(), &entry->key, &found);
if (!shared_hash_entry)
@ -1990,12 +1994,13 @@ pgsm_store(pgsmEntry *entry)
}
/*
* Get the memory address from DSA pointer and copy the query text in
* local variable
* Get the memory address from DSA pointer and copy the query text
* in local variable
*/
query_buff = dsa_get_address(query_dsa_area, dsa_query_pointer);
memcpy(query_buff, query, query_len);
/* Promotion to exclusive lock */
LWLockRelease(pgsm->lock);
LWLockAcquire(pgsm->lock, LW_EXCLUSIVE);
@ -2008,8 +2013,6 @@ pgsm_store(pgsmEntry *entry)
}
PG_CATCH();
{
LWLockRelease(pgsm->lock);
if (DsaPointerIsValid(dsa_query_pointer))
dsa_free(query_dsa_area, dsa_query_pointer);
PG_RE_THROW();
@ -2019,14 +2022,13 @@ pgsm_store(pgsmEntry *entry)
if (shared_hash_entry == NULL)
{
LWLockRelease(pgsm->lock);
if (DsaPointerIsValid(dsa_query_pointer))
dsa_free(query_dsa_area, dsa_query_pointer);
/*
* Out of memory; report only if the state has changed now.
* Otherwise we risk filling up the log file with these message.
* Otherwise we risk filling up the log file with these
* message.
*/
if (!IsSystemOOM())
{
@ -2042,6 +2044,8 @@ pgsm_store(pgsmEntry *entry)
} PGSM_END_DISABLE_ERROR_CAPTURE();
}
LWLockRelease(pgsm->lock);
return;
}
else
@ -2082,6 +2086,24 @@ pgsm_store(pgsmEntry *entry)
PGSM_STORE);
memset(&entry->counters, 0, sizeof(entry->counters));
}
PG_CATCH();
{
/*
* Force LWLock release in case of error because we need to aquire it
* again in pgsm_emit_log_hook
*
* On ereport with level >= ERROR Postgres resets
* InterruptHoldoffCount counter (see errfinish funcion in elog.c). We
* need to increment it to be able to release lock here.
*/
HOLD_INTERRUPTS(); /* Increments holdoff counter */
LWLockRelease(pgsm->lock); /* Decrements holdoff counter */
PG_RE_THROW();
}
PG_END_TRY();
LWLockRelease(pgsm->lock);
}