Fix error handling path in autovacuum launcher

alvherre · alvherre · commit 870da1e1546c · 2017-08-15T13:35:12.000-03:00
The original code (since 00e6a16) was assuming aborting the transaction in autovacuum launcher was sufficient to release all resources, but in reality the launcher runs quite a lot of code out of any transactions. Re-introduce individual cleanup calls to make abort more robust. Reported-by: Robert Haas Discussion: https://postgr.es/m/CA+TgmobQVbz4K_+RSmiM9HeRKpy3vS5xnbkL95gSEnWijzprKQ@mail.gmail.com
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
@@ -91,6 +91,7 @@
 #include "storage/proc.h"
 #include "storage/procsignal.h"
 #include "storage/sinvaladt.h"
+#include "storage/smgr.h"
 #include "tcop/tcopprot.h"
 #include "utils/dsa.h"
 #include "utils/fmgroids.h"
@@ -524,6 +525,26 @@ AutoVacLauncherMain(int argc, char *argv[])
 		/* Abort the current transaction in order to recover */
 		AbortCurrentTransaction();
 
+		/*
+		 * Release any other resources, for the case where we were not in a
+		 * transaction.
+		 */
+		LWLockReleaseAll();
+		pgstat_report_wait_end();
+		AbortBufferIO();
+		UnlockBuffers();
+		if (CurrentResourceOwner)
+		{
+			ResourceOwnerRelease(CurrentResourceOwner,
+								 RESOURCE_RELEASE_BEFORE_LOCKS,
+								 false, true);
+			/* we needn't bother with the other ResourceOwnerRelease phases */
+		}
+		AtEOXact_Buffers(false);
+		AtEOXact_SMgr();
+		AtEOXact_Files();
+		AtEOXact_HashTables(false);
+
 		/*
 		 * Now return to normal top-level context and clear ErrorContext for
 		 * next time.
