From: Teodor Sigaev <teodor@sigaev.ru>
Date: Thu, 3 May 2018 17:08:29 +0000 (+0300)
Subject: Add HOLD_INTERRUPTS section into FinishPreparedTransaction.
X-Git-Tag: REL_11_BETA1~105
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8f9be261f43772ccee2eae94d971bac6557cbe6a;p=postgresql

Add HOLD_INTERRUPTS section into FinishPreparedTransaction.

If an interrupt arrives in the middle of FinishPreparedTransaction
and any callback decide to call CHECK_FOR_INTERRUPTS (e.g.
RemoveTwoPhaseFile can write a warning with ereport, which checks for
interrupts) then it's possible to leave current GXact undeleted.

Backpatch to all supported branches

Stas Kelvich

Discussion: ihttps://www.postgresql.org/message-id/3AD85097-A3F3-4EBA-99BD-C38EDF8D2949@postgrespro.ru
---

diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index cdd8156ce4..65194db70e 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -1487,6 +1487,9 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	/* compute latestXid among all children */
 	latestXid = TransactionIdLatest(xid, hdr->nsubxacts, children);
 
+	/* Prevent cancel/die interrupt while cleaning up */
+	HOLD_INTERRUPTS();
+
 	/*
 	 * The order of operations here is critical: make the XLOG entry for
 	 * commit or abort, then mark the transaction committed or aborted in
@@ -1578,6 +1581,8 @@ FinishPreparedTransaction(const char *gid, bool isCommit)
 	LWLockRelease(TwoPhaseStateLock);
 	MyLockedGxact = NULL;
 
+	RESUME_INTERRUPTS();
+
 	pfree(buf);
 }