diff options
| -rw-r--r-- | fs/bcachefs/btree_locking.c | 54 | ||||
| -rw-r--r-- | fs/bcachefs/debug.c | 17 |
2 files changed, 50 insertions, 21 deletions
diff --git a/fs/bcachefs/btree_locking.c b/fs/bcachefs/btree_locking.c index 19062cea8774..b79543ae5eeb 100644 --- a/fs/bcachefs/btree_locking.c +++ b/fs/bcachefs/btree_locking.c @@ -71,11 +71,6 @@ struct lock_graph { unsigned nr; }; -static void lock_graph_pop(struct lock_graph *g) -{ - closure_put(&g->g[--g->nr].trans->ref); -} - static noinline void print_cycle(struct printbuf *out, struct lock_graph *g) { struct trans_waiting_for_lock *i; @@ -87,6 +82,18 @@ static noinline void print_cycle(struct printbuf *out, struct lock_graph *g) bch2_btree_trans_to_text(out, i->trans); } +static noinline void print_chain(struct printbuf *out, struct lock_graph *g) +{ + struct trans_waiting_for_lock *i; + + for (i = g->g; i != g->g + g->nr; i++) { + if (i != g->g) + prt_str(out, "<- "); + prt_printf(out, "%u ", i->trans->locking_wait.task->pid); + } + prt_newline(out); +} + static int abort_lock(struct lock_graph *g, struct trans_waiting_for_lock *i) { int ret; @@ -134,6 +141,21 @@ static noinline int break_cycle(struct lock_graph *g) BUG(); } +static void lock_graph_pop(struct lock_graph *g) +{ + closure_put(&g->g[--g->nr].trans->ref); +} + +static void lock_graph_pop_above(struct lock_graph *g, struct trans_waiting_for_lock *above, + struct printbuf *cycle) +{ + if (g->nr > 1 && cycle) + print_chain(cycle, g); + + while (g->g + g->nr > above) + lock_graph_pop(g); +} + static int lock_graph_descend(struct lock_graph *g, struct btree_trans *trans, struct printbuf *cycle) { @@ -142,11 +164,10 @@ static int lock_graph_descend(struct lock_graph *g, struct btree_trans *trans, int ret = 0; for (i = g->g; i < g->g + g->nr; i++) { - if (i->trans->locking != i->node_want) - while (g->g + g->nr >= i) { - lock_graph_pop(g); - return 0; - } + if (i->trans->locking != i->node_want) { + lock_graph_pop_above(g, i - 1, cycle); + return 0; + } if (i->trans == trans) { if (cycle) { @@ -185,20 +206,19 @@ static int lock_graph_descend(struct lock_graph *g, struct btree_trans *trans, return 0; deadlock: - while (g->nr) - lock_graph_pop(g); + lock_graph_pop_above(g, g->g, cycle); return ret; } -static noinline void lock_graph_remove_non_waiters(struct lock_graph *g) +static noinline void lock_graph_remove_non_waiters(struct lock_graph *g, + struct printbuf *cycle) { struct trans_waiting_for_lock *i; for (i = g->g + 1; i < g->g + g->nr; i++) if (i->trans->locking != i->node_want || i->trans->locking_wait.start_time != i[-1].lock_start_time) { - while (g->g + g->nr >= i) - lock_graph_pop(g); + lock_graph_pop_above(g, i - 1, cycle); return; } BUG(); @@ -252,7 +272,7 @@ next: b = &READ_ONCE(path->l[top->level].b)->c; if (unlikely(IS_ERR_OR_NULL(b))) { - lock_graph_remove_non_waiters(&g); + lock_graph_remove_non_waiters(&g, cycle); goto next; } @@ -286,6 +306,8 @@ next: } } + if (g.nr > 1 && cycle) + print_chain(cycle, &g); lock_graph_pop(&g); goto next; } diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c index 41b2772afef9..c7d558381388 100644 --- a/fs/bcachefs/debug.c +++ b/fs/bcachefs/debug.c @@ -725,11 +725,18 @@ static ssize_t bch2_btree_deadlock_read(struct file *file, char __user *buf, goto out; mutex_lock(&c->btree_trans_lock); - list_for_each_entry(trans, &c->btree_trans_list, list) - if (bch2_check_for_deadlock(trans, &i->buf)) { - i->iter = 1; - break; - } + list_for_each_entry(trans, &c->btree_trans_list, list) { + if (trans->locking_wait.task->pid <= i->iter) + continue; + + ret = flush_buf(i); + if (ret) + return ret; + + bch2_check_for_deadlock(trans, &i->buf); + + i->iter = trans->locking_wait.task->pid; + } mutex_unlock(&c->btree_trans_lock); out: if (i->buf.allocation_failure) |