Improve test case stability

Given unlucky timing, some of the new tests added by commit bc32a12e0db2
can fail spuriously.  We haven't seen such failures yet in buildfarm,
but allegedly we can prevent them with this tweak.

While at it, remove an unused injection point I (Álvaro) added.

Author: Mihail Nikalayeu <mihailnikalayeu@gmail.com>
Discussion: https://postgr.es/m/CADzfLwUc=jtSUEaQCtyt8zTeOJ-gHZ8=w_KJsVjDOYSLqaY9Lg@mail.gmail.com
Discussion: https://postgr.es/m/CADzfLwV5oQq-Vg_VmG_o4SdL6yHjDoNO4T4pMtgJLzYGmYf74g@mail.gmail.com

6 files changed, 45 insertions, 22 deletions

diff --git a/src/backend/executor/execIndexing.c b/src/backend/executor/execIndexing.c
index d1cbab58799..dd323c9b9fd 100644
--- a/src/backend/executor/execIndexing.c
+++ b/src/backend/executor/execIndexing.c
@@ -945,9 +945,7 @@ retry:
 	ExecDropSingleTupleTableSlot(existing_slot);
 
 #ifdef USE_INJECTION_POINTS
-	if (conflict)
-		INJECTION_POINT("check-exclusion-or-unique-constraint-conflict", NULL);
-	else
+	if (!conflict)
 		INJECTION_POINT("check-exclusion-or-unique-constraint-no-conflict", NULL);
 #endif
 
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index 24f73a49d27..434abbf6b6f 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -459,6 +459,7 @@ InvalidateCatalogSnapshot(void)
 		pairingheap_remove(&RegisteredSnapshots, &CatalogSnapshot->ph_node);
 		CatalogSnapshot = NULL;
 		SnapshotResetXmin();
+		INJECTION_POINT("pre-invalidate-catalog-snapshot-end", NULL);
 		INJECTION_POINT("invalidate-catalog-snapshot-end", NULL);
 	}
 }
diff --git a/src/test/modules/injection_points/expected/index-concurrently-upsert-predicate.out b/src/test/modules/injection_points/expected/index-concurrently-upsert-predicate.out
index af602bdc048..3d9512c8fc7 100644
--- a/src/test/modules/injection_points/expected/index-concurrently-upsert-predicate.out
+++ b/src/test/modules/injection_points/expected/index-concurrently-upsert-predicate.out
@@ -1,6 +1,6 @@
-Parsed test spec with 4 sessions
+Parsed test spec with 5 sessions
 
-starting permutation: s3_start_create_index s1_start_upsert s4_wakeup_define_index_before_set_valid s2_start_upsert s4_wakeup_s1_from_invalidate_catalog_snapshot s4_wakeup_s2 s4_wakeup_s1
+starting permutation: s5_noop s3_start_create_index s1_start_upsert s4_wakeup_define_index_before_set_valid s2_start_upsert s5_wakeup_s1_from_invalidate_catalog_snapshot s4_wakeup_s2 s4_wakeup_s1
 injection_points_attach
 -----------------------
                        
@@ -16,12 +16,16 @@ injection_points_attach
                        
 (1 row)
 
+step s5_noop: 
+ <waiting ...>
 step s3_start_create_index: 
 	CREATE UNIQUE INDEX CONCURRENTLY tbl_pkey_special_duplicate ON test.tbl(abs(i)) WHERE i < 10000;
  <waiting ...>
+s1: NOTICE:  notice triggered for injection point pre-invalidate-catalog-snapshot-end
 step s1_start_upsert: 
 	INSERT INTO test.tbl VALUES(13,now()) ON CONFLICT (abs(i)) WHERE i < 100 DO UPDATE SET updated_at = now();
  <waiting ...>
+step s5_noop: <... completed>
 step s4_wakeup_define_index_before_set_valid: 
 	SELECT injection_points_detach('define-index-before-set-valid');
 	SELECT injection_points_wakeup('define-index-before-set-valid');
@@ -39,7 +43,7 @@ injection_points_wakeup
 step s2_start_upsert: 
 	INSERT INTO test.tbl VALUES(13,now()) ON CONFLICT (abs(i)) WHERE i < 100 DO UPDATE SET updated_at = now();
  <waiting ...>
-step s4_wakeup_s1_from_invalidate_catalog_snapshot: 
+step s5_wakeup_s1_from_invalidate_catalog_snapshot: 
 	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
 	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
 
@@ -81,6 +85,7 @@ injection_points_wakeup
                        
 (1 row)
 
+s1: NOTICE:  notice triggered for injection point pre-invalidate-catalog-snapshot-end
 step s1_start_upsert: <... completed>
 step s2_start_upsert: <... completed>
 step s3_start_create_index: <... completed>
diff --git a/src/test/modules/injection_points/expected/index-concurrently-upsert.out b/src/test/modules/injection_points/expected/index-concurrently-upsert.out
index eb6fd9592df..a9e8bb5d00e 100644
--- a/src/test/modules/injection_points/expected/index-concurrently-upsert.out
+++ b/src/test/modules/injection_points/expected/index-concurrently-upsert.out
@@ -1,6 +1,6 @@
-Parsed test spec with 4 sessions
+Parsed test spec with 5 sessions
 
-starting permutation: s3_start_create_index s1_start_upsert s4_wakeup_define_index_before_set_valid s2_start_upsert s4_wakeup_s1_from_invalidate_catalog_snapshot s4_wakeup_s2 s4_wakeup_s1
+starting permutation: s5_noop s3_start_create_index s1_start_upsert s4_wakeup_define_index_before_set_valid s2_start_upsert s5_wakeup_s1_from_invalidate_catalog_snapshot s4_wakeup_s2 s4_wakeup_s1
 injection_points_attach
 -----------------------
                        
@@ -16,12 +16,16 @@ injection_points_attach
                        
 (1 row)
 
+step s5_noop: 
+ <waiting ...>
 step s3_start_create_index: 
 	CREATE UNIQUE INDEX CONCURRENTLY tbl_pkey_duplicate ON test.tbl(i);
  <waiting ...>
+s1: NOTICE:  notice triggered for injection point pre-invalidate-catalog-snapshot-end
 step s1_start_upsert: 
     INSERT INTO test.tbl VALUES (13,now()) ON CONFLICT (i) DO UPDATE SET updated_at = now();
  <waiting ...>
+step s5_noop: <... completed>
 step s4_wakeup_define_index_before_set_valid: 
 	SELECT injection_points_detach('define-index-before-set-valid');
 	SELECT injection_points_wakeup('define-index-before-set-valid');
@@ -39,7 +43,7 @@ injection_points_wakeup
 step s2_start_upsert: 
 	INSERT INTO test.tbl VALUES (13,now()) ON CONFLICT (i) DO UPDATE SET updated_at = now();
  <waiting ...>
-step s4_wakeup_s1_from_invalidate_catalog_snapshot: 
+step s5_wakeup_s1_from_invalidate_catalog_snapshot: 
 	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
 	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
 
@@ -81,6 +85,7 @@ injection_points_wakeup
                        
 (1 row)
 
+s1: NOTICE:  notice triggered for injection point pre-invalidate-catalog-snapshot-end
 step s1_start_upsert: <... completed>
 step s2_start_upsert: <... completed>
 step s3_start_create_index: <... completed>
diff --git a/src/test/modules/injection_points/specs/index-concurrently-upsert-predicate.spec b/src/test/modules/injection_points/specs/index-concurrently-upsert-predicate.spec
index 13897d88bce..725f6f22295 100644
--- a/src/test/modules/injection_points/specs/index-concurrently-upsert-predicate.spec
+++ b/src/test/modules/injection_points/specs/index-concurrently-upsert-predicate.spec
@@ -5,7 +5,7 @@
 # - s2: UPSERT the same tuple
 # - s3: CREATE UNIQUE INDEX CONCURRENTLY (with a predicate)
 #
-# - s4: control concurrency via injection points
+# - s4 and s5: control concurrency via injection points
 
 setup
 {
@@ -27,6 +27,7 @@ setup
 {
 	SELECT injection_points_set_local();
 	SELECT injection_points_attach('check-exclusion-or-unique-constraint-no-conflict', 'wait');
+	SELECT injection_points_attach('pre-invalidate-catalog-snapshot-end', 'notice');
 	SELECT injection_points_attach('invalidate-catalog-snapshot-end', 'wait');
 }
 step s1_start_upsert
@@ -62,11 +63,6 @@ step s4_wakeup_s1
 	SELECT injection_points_detach('check-exclusion-or-unique-constraint-no-conflict');
 	SELECT injection_points_wakeup('check-exclusion-or-unique-constraint-no-conflict');
 }
-step s4_wakeup_s1_from_invalidate_catalog_snapshot
-{
-	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
-	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
-}
 step s4_wakeup_s2
 {
 	SELECT injection_points_detach('exec-insert-before-insert-speculative');
@@ -78,11 +74,22 @@ step s4_wakeup_define_index_before_set_valid
 	SELECT injection_points_wakeup('define-index-before-set-valid');
 }
 
+session s5
+step s5_noop
+{
+}
+step s5_wakeup_s1_from_invalidate_catalog_snapshot
+{
+	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
+	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
+}
+
 permutation
+	s5_noop(s1_start_upsert notices 1)
 	s3_start_create_index(s1_start_upsert, s2_start_upsert)
 	s1_start_upsert
 	s4_wakeup_define_index_before_set_valid
 	s2_start_upsert(s1_start_upsert)
-	s4_wakeup_s1_from_invalidate_catalog_snapshot
+	s5_wakeup_s1_from_invalidate_catalog_snapshot
 	s4_wakeup_s2
 	s4_wakeup_s1
diff --git a/src/test/modules/injection_points/specs/index-concurrently-upsert.spec b/src/test/modules/injection_points/specs/index-concurrently-upsert.spec
index b07a6408b3b..4487834aa8e 100644
--- a/src/test/modules/injection_points/specs/index-concurrently-upsert.spec
+++ b/src/test/modules/injection_points/specs/index-concurrently-upsert.spec
@@ -26,6 +26,7 @@ setup
 {
 	SELECT injection_points_set_local();
 	SELECT injection_points_attach('check-exclusion-or-unique-constraint-no-conflict', 'wait');
+	SELECT injection_points_attach('pre-invalidate-catalog-snapshot-end', 'notice');
 	SELECT injection_points_attach('invalidate-catalog-snapshot-end', 'wait');
 }
 step s1_start_upsert
@@ -61,11 +62,6 @@ step s4_wakeup_s1
 	SELECT injection_points_detach('check-exclusion-or-unique-constraint-no-conflict');
 	SELECT injection_points_wakeup('check-exclusion-or-unique-constraint-no-conflict');
 }
-step s4_wakeup_s1_from_invalidate_catalog_snapshot
-{
-	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
-	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
-}
 step s4_wakeup_s2
 {
 	SELECT injection_points_detach('exec-insert-before-insert-speculative');
@@ -77,11 +73,22 @@ step s4_wakeup_define_index_before_set_valid
 	SELECT injection_points_wakeup('define-index-before-set-valid');
 }
 
+session s5
+step s5_noop
+{
+}
+step s5_wakeup_s1_from_invalidate_catalog_snapshot
+{
+	SELECT injection_points_detach('invalidate-catalog-snapshot-end');
+	SELECT injection_points_wakeup('invalidate-catalog-snapshot-end');
+}
+
 permutation
+	s5_noop(s1_start_upsert notices 1)
 	s3_start_create_index(s1_start_upsert, s2_start_upsert)
 	s1_start_upsert
 	s4_wakeup_define_index_before_set_valid
 	s2_start_upsert(s1_start_upsert)
-	s4_wakeup_s1_from_invalidate_catalog_snapshot
+	s5_wakeup_s1_from_invalidate_catalog_snapshot
 	s4_wakeup_s2
 	s4_wakeup_s1