68 	struct trans_waiting_for_lock	g[8];  member
72 static noinline void print_cycle(struct printbuf *out, struct lock_graph *g)  in print_cycle()  argument
76 	prt_printf(out, "Found lock cycle (%u entries):\n", g->nr);  in print_cycle()
78 	for (i = g->g; i < g->g + g->nr; i++) {  in print_cycle()
84 		bch2_prt_task_backtrace(out, task, i == g->g ? 5 : 1, GFP_NOWAIT);  in print_cycle()
88 static noinline void print_chain(struct printbuf *out, struct lock_graph *g)  in print_chain()  argument
92 	for (i = g->g; i != g->g + g->nr; i++) {  in print_chain()
94 		if (i != g->g)  in print_chain()
101 static void lock_graph_up(struct lock_graph *g)  in lock_graph_up()  argument
103 	closure_put(&g->g[--g->nr].trans->ref);  in lock_graph_up()
106 static noinline void lock_graph_pop_all(struct lock_graph *g)  in lock_graph_pop_all()  argument
108 	while (g->nr)  in lock_graph_pop_all()
109 		lock_graph_up(g);  in lock_graph_pop_all()
112 static void __lock_graph_down(struct lock_graph *g, struct btree_trans *trans)  in __lock_graph_down()  argument
114 	g->g[g->nr++] = (struct trans_waiting_for_lock) {  in __lock_graph_down()
121 static void lock_graph_down(struct lock_graph *g, struct btree_trans *trans)  in lock_graph_down()  argument
124 	__lock_graph_down(g, trans);  in lock_graph_down()
127 static bool lock_graph_remove_non_waiters(struct lock_graph *g)  in lock_graph_remove_non_waiters()  argument
131 	for (i = g->g + 1; i < g->g + g->nr; i++)  in lock_graph_remove_non_waiters()
134 			while (g->g + g->nr > i)  in lock_graph_remove_non_waiters()
135 				lock_graph_up(g);  in lock_graph_remove_non_waiters()
142 static void trace_would_deadlock(struct lock_graph *g, struct btree_trans *trans)  in trace_would_deadlock()  argument
152 		print_cycle(&buf, g);  in trace_would_deadlock()
159 static int abort_lock(struct lock_graph *g, struct trans_waiting_for_lock *i)  in abort_lock()  argument
161 	if (i == g->g) {  in abort_lock()
162 		trace_would_deadlock(g, i->trans);  in abort_lock()
182 static noinline int break_cycle(struct lock_graph *g, struct printbuf *cycle)  in break_cycle()  argument
188 	if (lock_graph_remove_non_waiters(g))  in break_cycle()
193 		print_cycle(cycle, g);  in break_cycle()
198 	for (i = g->g; i < g->g + g->nr; i++) {  in break_cycle()
210 		prt_printf(&buf, bch2_fmt(g->g->trans->c, "cycle of nofail locks"));  in break_cycle()
212 		for (i = g->g; i < g->g + g->nr; i++) {  in break_cycle()
229 	ret = abort_lock(g, abort);  in break_cycle()
232 		while (g->nr)  in break_cycle()
233 			lock_graph_up(g);  in break_cycle()
237 static int lock_graph_descend(struct lock_graph *g, struct btree_trans *trans,  in lock_graph_descend()  argument
240 	struct btree_trans *orig_trans = g->g->trans;  in lock_graph_descend()
243 	for (i = g->g; i < g->g + g->nr; i++)  in lock_graph_descend()
246 			return break_cycle(g, cycle);  in lock_graph_descend()
249 	if (g->nr == ARRAY_SIZE(g->g)) {  in lock_graph_descend()
255 		while (g->nr)  in lock_graph_descend()
256 			lock_graph_up(g);  in lock_graph_descend()
265 	__lock_graph_down(g, trans);  in lock_graph_descend()
276 	struct lock_graph g;  in bch2_check_for_deadlock()  local
282 	g.nr = 0;  in bch2_check_for_deadlock()
288 		trace_would_deadlock(&g, trans);  in bch2_check_for_deadlock()
292 	lock_graph_down(&g, trans);  in bch2_check_for_deadlock()
299 	if (!g.nr)  in bch2_check_for_deadlock()
302 	top = &g.g[g.nr - 1];  in bch2_check_for_deadlock()
339 				if (!lock_graph_remove_non_waiters(&g)) {  in bch2_check_for_deadlock()
349 					lock_graph_pop_all(&g);  in bch2_check_for_deadlock()
376 				ret = lock_graph_descend(&g, trans, cycle);  in bch2_check_for_deadlock()
386 	if (g.nr > 1 && cycle)  in bch2_check_for_deadlock()
387 		print_chain(cycle, &g);  in bch2_check_for_deadlock()
388 	lock_graph_up(&g);  in bch2_check_for_deadlock()