From a7da746c11777780f01475c6123bc1efeaefe508 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Tue, 26 Aug 2025 11:38:41 -0400 Subject: [PATCH] Do CHECK_FOR_INTERRUPTS inside, not before, scanGetItem. The CHECK_FOR_INTERRUPTS call in gingetbitmap turns out to be inadequate to prevent a long uninterruptible loop, because we now know a case where looping occurs within scanGetItem. While the next patch will fix the bug that caused that, it seems foolish to assume that no similar patterns are possible. Let's do the CFI within scanGetItem's retry loop, instead. This demonstrably allows canceling out of the loop exhibited in bug #19031. Bug: #19031 Reported-by: Tim Wood Author: Tom Lane Discussion: https://postgr.es/m/19031-0638148643d25548@postgresql.org Backpatch-through: 13 --- src/backend/access/gin/ginget.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/backend/access/gin/ginget.c b/src/backend/access/gin/ginget.c index d23100be107..24458c564c6 100644 --- a/src/backend/access/gin/ginget.c +++ b/src/backend/access/gin/ginget.c @@ -1315,6 +1315,8 @@ scanGetItem(IndexScanDesc scan, ItemPointerData advancePast, */ do { + CHECK_FOR_INTERRUPTS(); + ItemPointerSetMin(item); match = true; for (i = 0; i < so->nkeys && match; i++) @@ -1958,8 +1960,6 @@ gingetbitmap(IndexScanDesc scan, TIDBitmap *tbm) for (;;) { - CHECK_FOR_INTERRUPTS(); - if (!scanGetItem(scan, iptr, &iptr, &recheck)) break;