Add CHECK_FOR_INTERRUPTS in Evict{Rel,All}UnpinnedBuffers.

MasahikoSawada · MasahikoSawada · commit 71aa2e1147b9 · 2025-11-04T15:47:22.000-08:00
This commit adds CHECK_FOR_INTERRUPTS to the shared buffer iteration loops in EvictRelUnpinnedBuffers and EvictAllUnpinnedBuffers. These functions, used by pg_buffercache's pg_buffercache_evict_relation and pg_buffercache_evict_all, can now be interrupted during long-running operations. Backpatch to version 18, where these functions and their corresponding pg_buffercache functions were introduced. Author: Yuhang Qiu <iamqyh@gmail.com> Discussion: https://postgr.es/m/8DC280D4-94A2-4E7B-BAB9-C345891D0B78%40gmail.com Backpatch-through: 18
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
@@ -6683,6 +6683,8 @@ EvictAllUnpinnedBuffers(int32 *buffers_evicted, int32 *buffers_flushed,
 		uint32		buf_state;
 		bool		buffer_flushed;
 
+		CHECK_FOR_INTERRUPTS();
+
 		buf_state = pg_atomic_read_u32(&desc->state);
 		if (!(buf_state & BM_VALID))
 			continue;
@@ -6733,6 +6735,8 @@ EvictRelUnpinnedBuffers(Relation rel, int32 *buffers_evicted,
 		uint32		buf_state = pg_atomic_read_u32(&(desc->state));
 		bool		buffer_flushed;
 
+		CHECK_FOR_INTERRUPTS();
+
 		/* An unlocked precheck should be safe and saves some cycles. */
 		if ((buf_state & BM_VALID) == 0 ||
 			!BufTagMatchesRelFileLocator(&desc->tag, &rel->rd_locator))
