diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/access/heap/vacuumlazy.c | 6 | ||||
| -rw-r--r-- | src/backend/access/nbtree/nbtsort.c | 7 | ||||
| -rw-r--r-- | src/backend/storage/ipc/procarray.c | 17 | ||||
| -rw-r--r-- | src/include/storage/proc.h | 7 |
4 files changed, 35 insertions, 2 deletions
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index 24fa72983c1..8aab6e324e0 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -4161,6 +4161,12 @@ parallel_vacuum_main(dsm_segment *seg, shm_toc *toc) LVRelState vacrel; ErrorContextCallback errcallback; + /* + * A parallel vacuum worker must have only PROC_IN_VACUUM flag since we + * don't support parallel vacuum for autovacuum as of now. + */ + Assert(MyProc->statusFlags == PROC_IN_VACUUM); + lvshared = (LVShared *) shm_toc_lookup(toc, PARALLEL_VACUUM_KEY_SHARED, false); elevel = lvshared->elevel; diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index 5fa6ea8ad9a..78f78e7341b 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -1814,6 +1814,13 @@ _bt_parallel_build_main(dsm_segment *seg, shm_toc *toc) ResetUsage(); #endif /* BTREE_BUILD_STATS */ + /* + * The only possible status flag that can be set to the parallel worker is + * PROC_IN_SAFE_IC. + */ + Assert((MyProc->statusFlags == 0) || + (MyProc->statusFlags == PROC_IN_SAFE_IC)); + /* Set debug_query_string for individual workers first */ sharedquery = shm_toc_lookup(toc, PARALLEL_KEY_QUERY_TEXT, true); debug_query_string = sharedquery; diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index 0ccfb3a20a4..9a8429169fc 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -2637,6 +2637,10 @@ ProcArrayInstallImportedXmin(TransactionId xmin, * PGPROC of the transaction from which we imported the snapshot, rather than * an XID. * + * Note that this function also copies statusFlags from the source `proc` in + * order to avoid the case where MyProc's xmin needs to be skipped for + * computing xid horizon. + * * Returns true if successful, false if source xact is no longer running. */ bool @@ -2648,8 +2652,10 @@ ProcArrayInstallRestoredXmin(TransactionId xmin, PGPROC *proc) Assert(TransactionIdIsNormal(xmin)); Assert(proc != NULL); - /* Get lock so source xact can't end while we're doing this */ - LWLockAcquire(ProcArrayLock, LW_SHARED); + /* + * Get an exclusive lock so that we can copy statusFlags from source proc. + */ + LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE); /* * Be certain that the referenced PGPROC has an advertised xmin which is @@ -2662,7 +2668,14 @@ ProcArrayInstallRestoredXmin(TransactionId xmin, PGPROC *proc) TransactionIdIsNormal(xid) && TransactionIdPrecedesOrEquals(xid, xmin)) { + /* Install xmin */ MyProc->xmin = TransactionXmin = xmin; + + /* Flags being copied must be valid copy-able flags. */ + Assert((proc->statusFlags & (~PROC_COPYABLE_FLAGS)) == 0); + MyProc->statusFlags = proc->statusFlags; + ProcGlobal->statusFlags[MyProc->pgxactoff] = MyProc->statusFlags; + result = true; } diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index be67d8a8616..cfabfdbedf1 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -66,6 +66,13 @@ struct XidCache (PROC_IN_VACUUM | PROC_IN_SAFE_IC | PROC_VACUUM_FOR_WRAPAROUND) /* + * Flags that are valid to copy from another proc, the parallel leader + * process in practice. Currently, flags that are set during parallel + * vacuum and parallel index creation are allowed. + */ +#define PROC_COPYABLE_FLAGS (PROC_IN_VACUUM | PROC_IN_SAFE_IC) + +/* * We allow a small number of "weak" relation locks (AccessShareLock, * RowShareLock, RowExclusiveLock) to be recorded in the PGPROC structure * rather than the main lock table. This eases contention on the lock |