LU-10460 osd-zfs: Add tunables to disable sync

[fs/lustre-release.git] / lustre / osd-zfs / osd_handler.c

diff --git a/lustre/osd-zfs/osd_handler.c b/lustre/osd-zfs/osd_handler.c
index 2575460..74db348 100644 (file)
--- a/lustre/osd-zfs/osd_handler.c
+++ b/lustre/osd-zfs/osd_handler.c
@@ -66,6 +66,8 @@
 
 struct lu_context_key  osd_key;
 
+static int osd_txg_sync_delay_us = -1;
+
 /* Slab for OSD object allocation */
 struct kmem_cache *osd_object_kmem;
 
@@ -315,8 +317,12 @@ static int osd_trans_stop(const struct lu_env *env, struct dt_device *dt,
 
        osd_unlinked_list_emptify(env, osd, &unlinked, true);
 
-       if (sync)
-               txg_wait_synced(dmu_objset_pool(osd->od_os), txg);
+       if (sync) {
+               if (osd_txg_sync_delay_us < 0)
+                       txg_wait_synced(dmu_objset_pool(osd->od_os), txg);
+               else
+                       udelay(osd_txg_sync_delay_us);
+       }
 
        RETURN(rc);
 }
@@ -1550,6 +1556,10 @@ extern unsigned int osd_oi_count;
 module_param(osd_oi_count, int, 0444);
 MODULE_PARM_DESC(osd_oi_count, "Number of Object Index containers to be created, it's only valid for new filesystem.");
 
+module_param(osd_txg_sync_delay_us, int, 0644);
+MODULE_PARM_DESC(osd_txg_sync_delay_us,
+                "When zero or larger delay N usec instead of doing TXG sync");
+
 MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
 MODULE_DESCRIPTION("Lustre Object Storage Device ("LUSTRE_OSD_ZFS_NAME")");
 MODULE_VERSION(LUSTRE_VERSION_STRING);