ZTS: fix removal_condense_export test case

It's been observed in the CI that the required 25% of obsolete bytes
in the mapping can be to high a threshold for this test resulting in
condensing never being triggered and a test failure.  To prevent these
failures make the existing zfs_condense_indirect_obsolete_pct tuning
available so the obsolete percentage can be reduced from 25% to 5%
during this test.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #11869

man/man5/zfs-module-parameters.5

@@ -1445,6 +1445,19 @@ to throttle vdev removal speed.
 Default value: \fB0\fR (no throttle).
 .RE
 
+.sp
+.ne 2
+.na
+\fBzfs_condense_indirect_obsolete_pct\fR (int)
+.ad
+.RS 12n
+Minimum percent of obsolete bytes in vdev mapping required to attempt to
+condense (see \fBzfs_condense_indirect_vdevs_enable\fR). Intended for use
+with the test suite to facilitate triggering condensing as needed.
+.sp
+Default value: \fB25\fR%.
+.RE
+
 .sp
 .ne 2
 .na

module/zfs/vdev_indirect.c

@@ -181,7 +181,7 @@ int zfs_condense_indirect_vdevs_enable = B_TRUE;
  * condenses.  Higher values will condense less often (causing less
  * i/o); lower values will reduce the mapping size more quickly.
  */
-int zfs_indirect_condense_obsolete_pct = 25;
+int zfs_condense_indirect_obsolete_pct = 25;
 
 /*
  * Condense if the obsolete space map takes up more than this amount of
@@ -445,7 +445,7 @@ vdev_indirect_should_condense(vdev_t *vd)
 	 * by the mapping.
 	 */
 	if (bytes_obsolete * 100 / bytes_mapped >=
-	    zfs_indirect_condense_obsolete_pct &&
+	    zfs_condense_indirect_obsolete_pct &&
 	    mapping_size > zfs_condense_min_mapping_bytes) {
 		zfs_dbgmsg("should condense vdev %llu because obsolete "
 		    "spacemap covers %d%% of %lluMB mapping",
@@ -1892,6 +1892,9 @@ EXPORT_SYMBOL(vdev_obsolete_sm_object);
 ZFS_MODULE_PARAM(zfs_condense, zfs_condense_, indirect_vdevs_enable, INT, ZMOD_RW,
 	"Whether to attempt condensing indirect vdev mappings");
 
+ZFS_MODULE_PARAM(zfs_condense, zfs_condense_, indirect_obsolete_pct, INT, ZMOD_RW,
+	"Minimum obsolete percent of bytes in the mapping to attempt condensing");
+
 ZFS_MODULE_PARAM(zfs_condense, zfs_condense_, min_mapping_bytes, ULONG, ZMOD_RW,
 	"Don't bother condensing if the mapping uses less than this amount of "
 	"memory");

tests/test-runner/bin/zts-report.py.in

@@ -263,7 +263,6 @@ if sys.platform.startswith('freebsd'):
         'delegate/zfs_allow_003_pos': ['FAIL', known_reason],
         'inheritance/inherit_001_pos': ['FAIL', '11829'],
         'pool_checkpoint/checkpoint_zhack_feat': ['FAIL', '11854'],
-        'removal/removal_condense_export': ['FAIL', known_reason],
         'resilver/resilver_restart_001': ['FAIL', known_reason],
         'zvol/zvol_misc/zvol_misc_volmode': ['FAIL', known_reason],
     })

tests/zfs-tests/include/tunables.cfg

@@ -25,6 +25,7 @@ CHECKSUM_EVENTS_PER_SECOND	checksum_events_per_second	zfs_checksum_events_per_se
 COMMIT_TIMEOUT_PCT		commit_timeout_pct		zfs_commit_timeout_pct
 COMPRESSED_ARC_ENABLED		compressed_arc_enabled		zfs_compressed_arc_enabled
 CONDENSE_INDIRECT_COMMIT_ENTRY_DELAY_MS	condense.indirect_commit_entry_delay_ms	zfs_condense_indirect_commit_entry_delay_ms
+CONDENSE_INDIRECT_OBSOLETE_PCT	condense.indirect_obsolete_pct	zfs_condense_indirect_obsolete_pct
 CONDENSE_MIN_MAPPING_BYTES	condense.min_mapping_bytes	zfs_condense_min_mapping_bytes
 DBUF_CACHE_MAX_BYTES		dbuf_cache.max_bytes		dbuf_cache_max_bytes
 DEADMAN_CHECKTIME_MS		deadman.checktime_ms		zfs_deadman_checktime_ms

tests/zfs-tests/tests/functional/removal/removal_condense_export.ksh

@@ -24,6 +24,7 @@
 function reset
 {
 	log_must set_tunable64 CONDENSE_INDIRECT_COMMIT_ENTRY_DELAY_MS 0
+	log_must set_tunable64 CONDENSE_INDIRECT_OBSOLETE_PCT 25
 	log_must set_tunable64 CONDENSE_MIN_MAPPING_BYTES 131072
 	default_cleanup_noexit
 }
@@ -31,6 +32,7 @@ function reset
 default_setup_noexit "$DISKS" "true"
 log_onexit reset
 log_must set_tunable64 CONDENSE_INDIRECT_COMMIT_ENTRY_DELAY_MS 5000
+log_must set_tunable64 CONDENSE_INDIRECT_OBSOLETE_PCT 5
 log_must set_tunable64 CONDENSE_MIN_MAPPING_BYTES 1
 
 log_must zfs set recordsize=512 $TESTPOOL/$TESTFS