The difference between hlist_unhashed_lockless and hlist_unhashed is that _lockless version uses READ_ONCE to do the check. Since it is used without locks we must switch to the _lockless variant.
Also make locking clusters and adding to inflight_pios return result so we can track if they failed and where. https://virtuozzo.atlassian.net/browse/VSTOR-91821 Signed-off-by: Alexander Atanasov <alexander.atana...@virtuozzo.com> --- drivers/md/dm-ploop-map.c | 70 ++++++++++++++++++++++++++++++--------- 1 file changed, 54 insertions(+), 16 deletions(-) diff --git a/drivers/md/dm-ploop-map.c b/drivers/md/dm-ploop-map.c index 3b24778e0894..dc150c8050d9 100644 --- a/drivers/md/dm-ploop-map.c +++ b/drivers/md/dm-ploop-map.c @@ -498,17 +498,32 @@ static void ploop_dec_nr_inflight(struct ploop *ploop, struct pio *pio) } } -static void ploop_link_pio(struct hlist_head head[], struct pio *pio, +static int ploop_link_pio(struct hlist_head head[], struct pio *pio, u32 clu, bool exclusive) { struct hlist_head *slot = ploop_htable_slot(head, clu); + struct ploop *ploop = pio->ploop; + + if (exclusive) { + struct pio *pe = ploop_find_pio(head, clu); + + if (pe == pio) + return 1; - if (exclusive) - WARN_ON_ONCE(ploop_find_pio(head, clu) != NULL); + WARN_ON_ONCE(pe != NULL); - BUG_ON(!hlist_unhashed(&pio->hlist_node)); + if (pe) + PL_ERR("clu:%u already exclusively locked\n", clu); + } + + if (!hlist_unhashed_lockless(&pio->hlist_node)) { + PL_ERR("already hashed clu:%u e:%d\n", clu, exclusive); + WARN_ON_ONCE(1); + return 0; + } hlist_add_head(&pio->hlist_node, slot); pio->clu = clu; + return 1; } /* @@ -516,45 +531,55 @@ static void ploop_link_pio(struct hlist_head head[], struct pio *pio, * or from exclusive_bios_rbtree. BIOs from endio_list are requeued * to deferred_list. */ -static void ploop_unlink_pio(struct ploop *ploop, struct pio *pio, +static int ploop_unlink_pio(struct ploop *ploop, struct pio *pio, struct list_head *pio_list) { - BUG_ON(hlist_unhashed(&pio->hlist_node)); + if (hlist_unhashed_lockless(&pio->hlist_node)) { + WARN_ON_ONCE(1); + return 0; + } hlist_del_init(&pio->hlist_node); list_splice_tail_init(&pio->endio_list, pio_list); + return 1; } -static void ploop_add_cluster_lk(struct ploop *ploop, struct pio *pio, u32 clu) +static int ploop_add_cluster_lk(struct ploop *ploop, struct pio *pio, u32 clu) { unsigned long flags; + int ret; spin_lock_irqsave(&ploop->deferred_lock, flags); - ploop_link_pio(ploop->exclusive_pios, pio, clu, true); + ret = ploop_link_pio(ploop->exclusive_pios, pio, clu, true); spin_unlock_irqrestore(&ploop->deferred_lock, flags); + return ret; } -static void ploop_del_cluster_lk(struct ploop *ploop, struct pio *pio) +static int ploop_del_cluster_lk(struct ploop *ploop, struct pio *pio) { LIST_HEAD(pio_list); unsigned long flags; + int ret; spin_lock_irqsave(&ploop->deferred_lock, flags); - ploop_unlink_pio(ploop, pio, &pio_list); + ret = ploop_unlink_pio(ploop, pio, &pio_list); spin_unlock_irqrestore(&ploop->deferred_lock, flags); if (!list_empty(&pio_list)) ploop_dispatch_pios(ploop, NULL, &pio_list); + return ret; } -static void ploop_link_submitting_pio(struct ploop *ploop, struct pio *pio, +static int ploop_link_submitting_pio(struct ploop *ploop, struct pio *pio, u32 clu) { unsigned long flags; + int ret; spin_lock_irqsave(&ploop->inflight_lock, flags); - ploop_link_pio(ploop->inflight_pios, pio, clu, false); + ret = ploop_link_pio(ploop->inflight_pios, pio, clu, false); spin_unlock_irqrestore(&ploop->inflight_lock, flags); + return ret; } static void ploop_unlink_completed_pio(struct ploop *ploop, struct pio *pio) @@ -562,7 +587,7 @@ static void ploop_unlink_completed_pio(struct ploop *ploop, struct pio *pio) LIST_HEAD(pio_list); unsigned long flags; - if (hlist_unhashed(&pio->hlist_node)) + if (hlist_unhashed_lockless(&pio->hlist_node)) return; spin_lock_irqsave(&ploop->inflight_lock, flags); @@ -706,7 +731,8 @@ static int ploop_handle_discard_pio(struct ploop *ploop, struct pio *pio, return 0; } - ploop_add_cluster_lk(ploop, pio, clu); + if (!ploop_add_cluster_lk(ploop, pio, clu)) + PL_ERR("dis clu %d already locked\n", clu); pio->wants_discard_index_cleanup = true; punch_hole: @@ -1429,7 +1455,8 @@ static int ploop_submit_cluster_cow(struct ploop *ploop, unsigned int level, cow->aux_pio = aux_pio; cow->cow_pio = cow_pio; - ploop_add_cluster_lk(ploop, cow_pio, clu); + if (!ploop_add_cluster_lk(ploop, cow_pio, clu)) + PL_ERR("cowclu %d already locked\n", clu); /* Stage #0: read secondary delta full clu */ ploop_map_and_submit_rw(ploop, dst_clu, aux_pio, level); @@ -1706,8 +1733,19 @@ static int ploop_process_one_deferred_bio(struct ploop *ploop, struct pio *pio) &dst_clu, pio); if (!ret) goto executed; + queue: /* pio needs to go to the queue */ - ploop_link_submitting_pio(ploop, pio, clu); + if (!ploop_link_submitting_pio(ploop, pio, clu)) { + PL_ERR("link submitting pio failed\n"); + /* Pio is put into endio_list */ + if (ploop_postpone_if_cluster_locked(ploop, pio, clu)) { + goto handled; + } else { + PL_ERR("link submitting pio postpone failed\n"); + WARN_ON_ONCE(1); + /* fail thru and run it anyway nothing */ + } + } ploop_map_and_submit_rw(ploop, dst_clu, pio, ploop_top_level(ploop)); // return 1; executed: /* pio op started */ -- 2.43.0 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
