static boolean_t dsl_scan_check_resume(dsl_scan_t *scn, const dnode_phys_t *dnp, const zbookmark_t *zb) { /* * We never skip over user/group accounting objects (obj<0) */ if (!ZB_IS_ZERO(&scn->scn_phys.scn_bookmark) && (int64_t)zb->zb_object >= 0) { /* * If we already visited this bp & everything below (in * a prior txg sync), don't bother doing it again. */ if (zbookmark_is_before(dnp, zb, &scn->scn_phys.scn_bookmark)) return (B_TRUE); /* * If we found the block we're trying to resume from, or * we went past it to a different object, zero it out to * indicate that it's OK to start checking for pausing * again. */ if (bcmp(zb, &scn->scn_phys.scn_bookmark, sizeof (*zb)) == 0 || zb->zb_object > scn->scn_phys.scn_bookmark.zb_object) { dprintf("resuming at %llx/%llx/%llx/%llx\n", (longlong_t)zb->zb_objset, (longlong_t)zb->zb_object, (longlong_t)zb->zb_level, (longlong_t)zb->zb_blkid); bzero(&scn->scn_phys.scn_bookmark, sizeof (*zb)); } } return (B_FALSE); }
/* * Returns RESUME_SKIP_ALL if td indicates that we are resuming a traversal and * the block indicated by zb does not need to be visited at all. Returns * RESUME_SKIP_CHILDREN if we are resuming a post traversal and we reach the * resume point. This indicates that this block should be visited but not its * children (since they must have been visited in a previous traversal). * Otherwise returns RESUME_SKIP_NONE. */ static resume_skip_t resume_skip_check(traverse_data_t *td, const dnode_phys_t *dnp, const zbookmark_t *zb) { if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) { /* * If we already visited this bp & everything below, * don't bother doing it again. */ if (zbookmark_is_before(dnp, zb, td->td_resume)) return (RESUME_SKIP_ALL); /* * If we found the block we're trying to resume from, zero * the bookmark out to indicate that we have resumed. */ ASSERT3U(zb->zb_object, <=, td->td_resume->zb_object); if (bcmp(zb, td->td_resume, sizeof (*zb)) == 0) { bzero(td->td_resume, sizeof (*zb)); if (td->td_flags & TRAVERSE_POST) return (RESUME_SKIP_CHILDREN); } } return (RESUME_SKIP_NONE); }
static boolean_t dsl_scan_check_pause(dsl_scan_t *scn, const zbookmark_t *zb) { uint64_t elapsed_nanosecs; int mintime; /* we never skip user/group accounting objects */ if (zb && (int64_t)zb->zb_object < 0) return (B_FALSE); if (scn->scn_pausing) return (B_TRUE); /* we're already pausing */ if (!ZB_IS_ZERO(&scn->scn_phys.scn_bookmark)) return (B_FALSE); /* we're resuming */ /* We only know how to resume from level-0 blocks. */ if (zb && zb->zb_level != 0) return (B_FALSE); mintime = (scn->scn_phys.scn_func == POOL_SCAN_RESILVER) ? zfs_resilver_min_time_ms : zfs_scan_min_time_ms; elapsed_nanosecs = gethrtime() - scn->scn_sync_start_time; if (elapsed_nanosecs / NANOSEC > zfs_txg_timeout || (NSEC2MSEC(elapsed_nanosecs) > mintime && txg_sync_waiting(scn->scn_dp)) || spa_shutting_down(scn->scn_dp->dp_spa)) { if (zb) { dprintf("pausing at bookmark %llx/%llx/%llx/%llx\n", (longlong_t)zb->zb_objset, (longlong_t)zb->zb_object, (longlong_t)zb->zb_level, (longlong_t)zb->zb_blkid); scn->scn_phys.scn_bookmark = *zb; } dprintf("pausing at DDT bookmark %llx/%llx/%llx/%llx\n", (longlong_t)scn->scn_phys.scn_ddt_bookmark.ddb_class, (longlong_t)scn->scn_phys.scn_ddt_bookmark.ddb_type, (longlong_t)scn->scn_phys.scn_ddt_bookmark.ddb_checksum, (longlong_t)scn->scn_phys.scn_ddt_bookmark.ddb_cursor); scn->scn_pausing = B_TRUE; return (B_TRUE); } return (B_FALSE); }
static void traverse_prefetch_metadata(traverse_data_t *td, const blkptr_t *bp, const zbookmark_t *zb) { uint32_t flags = ARC_NOWAIT | ARC_PREFETCH; if (!(td->td_flags & TRAVERSE_PREFETCH_METADATA)) return; /* * If we are in the process of resuming, don't prefetch, because * some children will not be needed (and in fact may have already * been freed). */ if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) return; if (BP_IS_HOLE(bp) || bp->blk_birth <= td->td_min_txg) return; if (BP_GET_LEVEL(bp) == 0 && BP_GET_TYPE(bp) != DMU_OT_DNODE) return; (void) arc_read(NULL, td->td_spa, bp, NULL, NULL, ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); }