[WIP] Fix "add_nested_replacing_spare" test case

Use 'zpool reopen' instead of 'zpool scrub' to kick in the spare device:
this is required to avoid spurious failures caused by a race condition
in events processing by the ZFS Event Daemon:

P1 (zpool scrub)                            P2 (zed)
---
zfs_ioc_pool_scan()
 -> dsl_scan()
  -> vdev_reopen()
   -> vdev_set_state(VDEV_STATE_CANT_OPEN)
                                            zfs_ioc_vdev_attach()
                                             -> spa_vdev_attach()
                                              -> dsl_resilver_restart()
  -> dsl_sync_task()
   -> dsl_scan_setup_check()
   <- dsl_scan_setup_check(): EBUSY

Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Requires-builders: test

TEST

@@ -5,25 +5,25 @@
 #TEST_PREPARE_SHARES="yes"
 
 ### SPLAT
-#TEST_SPLAT_SKIP="yes"
+TEST_SPLAT_SKIP="yes"
 #TEST_SPLAT_OPTIONS="-acvx"
 
 ### ztest
-#TEST_ZTEST_SKIP="yes"
+TEST_ZTEST_SKIP="yes"
 #TEST_ZTEST_TIMEOUT=1800
 #TEST_ZTEST_DIR="/var/tmp/"
 #TEST_ZTEST_OPTIONS="-V"
 #TEST_ZTEST_CORE_DIR="/mnt/zloop"
 
 ### zimport
-#TEST_ZIMPORT_SKIP="yes"
+TEST_ZIMPORT_SKIP="yes"
 #TEST_ZIMPORT_DIR="/var/tmp/zimport"
 #TEST_ZIMPORT_VERSIONS="master installed"
 #TEST_ZIMPORT_POOLS="zol-0.6.1 zol-0.6.2 master installed"
 #TEST_ZIMPORT_OPTIONS="-c"
 
 ### xfstests
-#TEST_XFSTESTS_SKIP="yes"
+TEST_XFSTESTS_SKIP="yes"
 #TEST_XFSTESTS_URL="https://github.com/behlendorf/xfstests/archive/"
 #TEST_XFSTESTS_VER="zfs.tar.gz"
 #TEST_XFSTESTS_POOL="tank"
@@ -39,10 +39,11 @@
 #TEST_ZFSTESTS_ITERS="1"
 #TEST_ZFSTESTS_OPTIONS="-vx"
 #TEST_ZFSTESTS_RUNFILE="linux.run"
+TEST_ZFSTESTS_RUNFILE="temp.run"
 #TEST_ZFSTESTS_TAGS="functional"
 
 ### zfsstress
-#TEST_ZFSSTRESS_SKIP="yes"
+TEST_ZFSSTRESS_SKIP="yes"
 #TEST_ZFSSTRESS_URL="https://github.com/nedbass/zfsstress/archive/"
 #TEST_ZFSSTRESS_VER="master.tar.gz"
 #TEST_ZFSSTRESS_RUNTIME=300

module/zfs/zfs_ioctl.c

@@ -1732,12 +1732,12 @@ zfs_ioc_pool_scan(zfs_cmd_t *zc)
 	spa_t *spa;
 	int error;
 
-	if ((error = spa_open(zc->zc_name, &spa, FTAG)) != 0)
-		return (error);
-
 	if (zc->zc_flags >= POOL_SCRUB_FLAGS_END)
 		return (SET_ERROR(EINVAL));
 
+	if ((error = spa_open(zc->zc_name, &spa, FTAG)) != 0)
+		return (error);
+
 	if (zc->zc_flags == POOL_SCRUB_PAUSE)
 		error = spa_scrub_pause_resume(spa, POOL_SCRUB_PAUSE);
 	else if (zc->zc_cookie == POOL_SCAN_NONE)

tests/runfiles/temp.run

@@ -0,0 +1,50 @@
+#
+# This file and its contents are supplied under the terms of the
+# Common Development and Distribution License ("CDDL"), version 1.0.
+# You may only use this file in accordance with the terms of version
+# 1.0 of the CDDL.
+#
+# A full copy of the text of the CDDL should have accompanied this
+# source.  A copy of the CDDL is also available via the Internet at
+# http://www.illumos.org/license/CDDL.
+#
+
+[DEFAULT]
+pre = setup
+quiet = False
+pre_user = root
+user = root
+timeout = 600
+post_user = root
+post = cleanup
+outputdir = /var/tmp/test_results
+tags = ['functional']
+
+[tests/functional/cli_root/zpool_add]
+tests = ['add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare',
+    'add_nested_replacing_spare', 'add_nested_replacing_spare']
+tags = ['functional', 'cli_root', 'zpool_add']
+

tests/zfs-tests/tests/functional/cli_root/zpool_add/add_nested_replacing_spare.ksh

@@ -79,7 +79,7 @@ do
 
 	# 2.1 Fault a device, verify the spare is kicked in
 	log_must zinject -d $FAULT_DEV -e nxio -T all -f 100 $TESTPOOL
-	log_must zpool scrub $TESTPOOL
+	log_must zpool reopen $TESTPOOL
 	log_must wait_vdev_state $TESTPOOL $FAULT_DEV "UNAVAIL" 60
 	log_must wait_vdev_state $TESTPOOL $SPARE_DEV1 "ONLINE" 60
 	log_must wait_hotspare_state $TESTPOOL $SPARE_DEV1 "INUSE"