OpenZFS 8959 - Add notifications when a scrub is paused or resumed

Authored by: Sean Eric Fagan <[email protected]>
Reviewed by: Alek Pinchuk <[email protected]>
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed-by: George Melikov <[email protected]>
Reviewed-by: Tony Hutter <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Approved by: Gordon Ross <[email protected]>
Ported-by: Giuseppe Di Natale <[email protected]>

Porting Notes:
- Brought #defines in eventdefs.h in line with ZFS on Linux format.
- Updated zfs-events.5 with the new events.

OpenZFS-issue: https://www.illumos.org/issues/8959
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/c862b93eea
Closes #7049

3 files changed, 36 insertions, 2 deletions

diff --git a/include/sys/sysevent/eventdefs.h b/include/sys/sysevent/eventdefs.h
index 825d88a7b..aa13bd505 100644
--- a/include/sys/sysevent/eventdefs.h
+++ b/include/sys/sysevent/eventdefs.h
@@ -110,6 +110,9 @@ extern "C" {
 #define	ESC_ZFS_CONFIG_SYNC		"config_sync"
 #define	ESC_ZFS_SCRUB_START		"scrub_start"
 #define	ESC_ZFS_SCRUB_FINISH		"scrub_finish"
+#define	ESC_ZFS_SCRUB_ABORT		"scrub_abort"
+#define	ESC_ZFS_SCRUB_RESUME		"scrub_resume"
+#define	ESC_ZFS_SCRUB_PAUSED		"scrub_paused"
 #define	ESC_ZFS_VDEV_SPARE		"vdev_spare"
 #define	ESC_ZFS_VDEV_AUTOEXPAND		"vdev_autoexpand"
 #define	ESC_ZFS_BOOTFS_VDEV_ATTACH	"bootfs_vdev_attach"
diff --git a/man/man5/zfs-events.5 b/man/man5/zfs-events.5
index 398ea8ad1..5cef4f539 100644
--- a/man/man5/zfs-events.5
+++ b/man/man5/zfs-events.5
@@ -328,7 +328,34 @@ Issued when a scrub is started on a pool.
 \fBscrub.finish\fR
 .ad
 .RS 12n
-Issued when a pool have finished scrubbing.
+Issued when a pool has finished scrubbing.
+.RE
+
+.sp
+.ne 2
+.na
+\fBscrub.abort\fR
+.ad
+.RS 12n
+Issued when a scrub is aborted on a pool.
+.RE
+
+.sp
+.ne 2
+.na
+\fBscrub.resume\fR
+.ad
+.RS 12n
+Issued when a scrub is resumed on a pool.
+.RE
+
+.sp
+.ne 2
+.na
+\fBscrub.paused\fR
+.ad
+.RS 12n
+Issued when a scrub is paused on a pool.
 .RE
 
 .sp
diff --git a/module/zfs/dsl_scan.c b/module/zfs/dsl_scan.c
index de579d1c7..2231ef1c0 100644
--- a/module/zfs/dsl_scan.c
+++ b/module/zfs/dsl_scan.c
@@ -714,8 +714,10 @@ dsl_scan(dsl_pool_t *dp, pool_scan_func_t func)
 		/* got scrub start cmd, resume paused scrub */
 		int err = dsl_scrub_set_pause_resume(scn->scn_dp,
 		    POOL_SCRUB_NORMAL);
-		if (err == 0)
+		if (err == 0) {
+			spa_event_notify(spa, NULL, NULL, ESC_ZFS_SCRUB_RESUME);
 			return (ECANCELED);
+		}
 
 		return (SET_ERROR(err));
 	}
@@ -842,6 +844,7 @@ dsl_scan_cancel_sync(void *arg, dmu_tx_t *tx)
 
 	dsl_scan_done(scn, B_FALSE, tx);
 	dsl_scan_sync_state(scn, tx, SYNC_MANDATORY);
+	spa_event_notify(scn->scn_dp->dp_spa, NULL, NULL, ESC_ZFS_SCRUB_ABORT);
 }
 
 int
@@ -886,6 +889,7 @@ dsl_scrub_pause_resume_sync(void *arg, dmu_tx_t *tx)
 		spa->spa_scan_pass_scrub_pause = gethrestime_sec();
 		scn->scn_phys.scn_flags |= DSF_SCRUB_PAUSED;
 		dsl_scan_sync_state(scn, tx, SYNC_CACHED);
+		spa_event_notify(spa, NULL, NULL, ESC_ZFS_SCRUB_PAUSED);
 	} else {
 		ASSERT3U(*cmd, ==, POOL_SCRUB_NORMAL);
 		if (dsl_scan_is_paused_scrub(scn)) {