diff options
Diffstat (limited to 'slabs.c')
| -rw-r--r-- | slabs.c | 63 |
1 files changed, 35 insertions, 28 deletions
@@ -498,7 +498,7 @@ static int slab_rebalance_start(void) { } enum move_status { - MOVE_PASS=0, MOVE_DONE, MOVE_BUSY + MOVE_PASS=0, MOVE_DONE, MOVE_BUSY, MOVE_LOCKED }; /* refcount == 0 is safe since nobody can incr while cache_lock is held. @@ -522,36 +522,42 @@ static int slab_rebalance_move(void) { item *it = slab_rebal.slab_pos; status = MOVE_PASS; if (it->slabs_clsid != 255) { - refcount = refcount_incr(&it->refcount); - if (refcount == 1) { /* item is unlinked, unused */ - if (it->it_flags & ITEM_SLABBED) { - /* remove from slab freelist */ - if (s_cls->slots == it) { - s_cls->slots = it->next; + uint32_t hv = hash(ITEM_key(it), it->nkey, 0); + if (item_trylock(hv) != 0) { + status = MOVE_LOCKED; + } else { + refcount = refcount_incr(&it->refcount); + if (refcount == 1) { /* item is unlinked, unused */ + if (it->it_flags & ITEM_SLABBED) { + /* remove from slab freelist */ + if (s_cls->slots == it) { + s_cls->slots = it->next; + } + if (it->next) it->next->prev = it->prev; + if (it->prev) it->prev->next = it->next; + s_cls->sl_curr--; + status = MOVE_DONE; + } else { + status = MOVE_BUSY; + } + } else if (refcount == 2) { /* item is linked but not busy */ + if ((it->it_flags & ITEM_LINKED) != 0) { + do_item_unlink_nolock(it, hash(ITEM_key(it), it->nkey, 0)); + status = MOVE_DONE; + } else { + /* refcount == 1 + !ITEM_LINKED means the item is being + * uploaded to, or was just unlinked but hasn't been freed + * yet. Let it bleed off on its own and try again later */ + status = MOVE_BUSY; } - if (it->next) it->next->prev = it->prev; - if (it->prev) it->prev->next = it->next; - s_cls->sl_curr--; - status = MOVE_DONE; - } else { - status = MOVE_BUSY; - } - } else if (refcount == 2) { /* item is linked but not busy */ - if ((it->it_flags & ITEM_LINKED) != 0) { - do_item_unlink_nolock(it, hash(ITEM_key(it), it->nkey, 0)); - status = MOVE_DONE; } else { - /* refcount == 1 + !ITEM_LINKED means the item is being - * uploaded to, or was just unlinked but hasn't been freed - * yet. Let it bleed off on its own and try again later */ + if (settings.verbose > 2) { + fprintf(stderr, "Slab reassign hit a busy item: refcount: %d (%d -> %d)\n", + it->refcount, slab_rebal.s_clsid, slab_rebal.d_clsid); + } status = MOVE_BUSY; } - } else { - if (settings.verbose > 2) { - fprintf(stderr, "Slab reassign hit a busy item: refcount: %d (%d -> %d)\n", - it->refcount, slab_rebal.s_clsid, slab_rebal.d_clsid); - } - status = MOVE_BUSY; + item_unlock(hv); } } @@ -562,9 +568,10 @@ static int slab_rebalance_move(void) { it->slabs_clsid = 255; break; case MOVE_BUSY: + refcount_decr(&it->refcount); + case MOVE_LOCKED: slab_rebal.busy_items++; was_busy++; - refcount_decr(&it->refcount); break; case MOVE_PASS: break; |