Commit 32ed4a62 authored by Kent Overstreet's avatar Kent Overstreet Committed by Kent Overstreet
Browse files

bcachefs: Btree path tracepoints 



Fastpath tracepoints, rarely needed, only enabled with
CONFIG_BCACHEFS_PATH_TRACEPOINTS.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent abbfc4db

fs/bcachefs/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -87,6 +87,13 @@ config BCACHEFS_SIX_OPTIMISTIC_SPIN 
	is held by another thread, spin for a short while, as long as the

	thread owning the lock is running.



config BCACHEFS_PATH_TRACEPOINTS

	bool "Extra btree_path tracepoints"

	depends on BCACHEFS_FS

	help

	Enable extra tracepoints for debugging btree_path operations; we don't

	normally want these enabled because they happen at very high rates.



config MEAN_AND_VARIANCE_UNIT_TEST

	tristate "mean_and_variance unit tests" if !KUNIT_ALL_TESTS

	depends on KUNIT

fs/bcachefs/btree_iter.c

+26 −12
Original line number Diff line number Diff line
@@ -1131,6 +1131,8 @@ int bch2_btree_path_traverse_one(struct btree_trans *trans, 
	if (unlikely(!trans->srcu_held))

		bch2_trans_srcu_lock(trans);



	trace_btree_path_traverse_start(trans, path);



	/*

	 * Ensure we obey path->should_be_locked: if it's set, we can't unlock

	 * and re-traverse the path without a transaction restart:
@@ -1194,6 +1196,7 @@ int bch2_btree_path_traverse_one(struct btree_trans *trans, 


out_uptodate:

	path->uptodate = BTREE_ITER_UPTODATE;

	trace_btree_path_traverse_end(trans, path);

out:

	if (bch2_err_matches(ret, BCH_ERR_transaction_restart) != !!trans->restarted)

		panic("ret %s (%i) trans->restarted %s (%i)\n",
@@ -1236,8 +1239,10 @@ __flatten 
btree_path_idx_t __bch2_btree_path_make_mut(struct btree_trans *trans,

			btree_path_idx_t path, bool intent, unsigned long ip)

{

	struct btree_path *old = trans->paths + path;

	__btree_path_put(trans, trans->paths + path, intent);

	path = btree_path_clone(trans, path, intent, ip);

	trace_btree_path_clone(trans, old, trans->paths + path);

	trans->paths[path].preserve = false;

	return path;

}
@@ -1252,6 +1257,8 @@ __bch2_btree_path_set_pos(struct btree_trans *trans, 
	bch2_trans_verify_not_in_restart(trans);

	EBUG_ON(!trans->paths[path_idx].ref);



	trace_btree_path_set_pos(trans, trans->paths + path_idx, &new_pos);



	path_idx = bch2_btree_path_make_mut(trans, path_idx, intent, ip);



	struct btree_path *path = trans->paths + path_idx;
@@ -1368,6 +1375,8 @@ void bch2_path_put(struct btree_trans *trans, btree_path_idx_t path_idx, bool in 
		? have_path_at_pos(trans, path)

		: have_node_at_pos(trans, path);



	trace_btree_path_free(trans, path_idx, dup);



	if (!dup && !(!path->preserve && !is_btree_node(path, path->level)))

		return;
@@ -1421,8 +1430,8 @@ void __noreturn bch2_trans_unlocked_error(struct btree_trans *trans) 
noinline __cold

void bch2_trans_updates_to_text(struct printbuf *buf, struct btree_trans *trans)

{

	prt_printf(buf, "transaction updates for %s journal seq %llu\n",

	       trans->fn, trans->journal_res.seq);

	prt_printf(buf, "%u transaction updates for %s journal seq %llu\n",

		   trans->nr_updates, trans->fn, trans->journal_res.seq);

	printbuf_indent_add(buf, 2);



	trans_for_each_update(trans, i) {
@@ -1464,7 +1473,7 @@ static void bch2_btree_path_to_text_short(struct printbuf *out, struct btree_tra 
{

	struct btree_path *path = trans->paths + path_idx;



	prt_printf(out, "path: idx %2u ref %u:%u %c %c %c btree=%s l=%u pos ",

	prt_printf(out, "path: idx %3u ref %u:%u %c %c %c btree=%s l=%u pos ",

		   path_idx, path->ref, path->intent_ref,

		   path->preserve ? 'P' : ' ',

		   path->should_be_locked ? 'S' : ' ',
@@ -1716,6 +1725,8 @@ btree_path_idx_t bch2_path_get(struct btree_trans *trans, 
	    trans->paths[path_pos].cached	== cached &&

	    trans->paths[path_pos].btree_id	== btree_id &&

	    trans->paths[path_pos].level	== level) {

		trace_btree_path_get(trans, trans->paths + path_pos, &pos);



		__btree_path_get(trans, trans->paths + path_pos, intent);

		path_idx = bch2_btree_path_set_pos(trans, path_pos, pos, intent, ip);

		path = trans->paths + path_idx;
@@ -1738,6 +1749,8 @@ btree_path_idx_t bch2_path_get(struct btree_trans *trans, 
		path->ip_allocated		= ip;

#endif

		trans->paths_sorted		= false;



		trace_btree_path_alloc(trans, path);

	}



	if (!(flags & BTREE_ITER_nopreserve))
@@ -1857,7 +1870,7 @@ bch2_btree_iter_traverse(struct btree_iter *iter) 


	struct btree_path *path = btree_iter_path(trans, iter);

	if (btree_path_node(path, path->level))

		btree_path_set_should_be_locked(path);

		btree_path_set_should_be_locked(trans, path);

	return 0;

}
@@ -1889,7 +1902,7 @@ struct btree *bch2_btree_iter_peek_node(struct btree_iter *iter) 
	iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,

					iter->flags & BTREE_ITER_intent,

					btree_iter_ip_allocated(iter));

	btree_path_set_should_be_locked(btree_iter_path(trans, iter));

	btree_path_set_should_be_locked(trans, btree_iter_path(trans, iter));

out:

	bch2_btree_iter_verify_entry_exit(iter);

	bch2_btree_iter_verify(iter);
@@ -1983,7 +1996,7 @@ struct btree *bch2_btree_iter_next_node(struct btree_iter *iter) 
	iter->path = bch2_btree_path_set_pos(trans, iter->path, b->key.k.p,

					iter->flags & BTREE_ITER_intent,

					btree_iter_ip_allocated(iter));

	btree_path_set_should_be_locked(btree_iter_path(trans, iter));

	btree_path_set_should_be_locked(trans, btree_iter_path(trans, iter));

	EBUG_ON(btree_iter_path(trans, iter)->uptodate);

out:

	bch2_btree_iter_verify_entry_exit(iter);
@@ -2155,7 +2168,7 @@ struct bkey_s_c btree_trans_peek_key_cache(struct btree_iter *iter, struct bpos 
	if (unlikely(ret))

		return bkey_s_c_err(ret);



	btree_path_set_should_be_locked(trans->paths + iter->key_cache_path);

	btree_path_set_should_be_locked(trans, trans->paths + iter->key_cache_path);



	k = bch2_btree_path_peek_slot(trans->paths + iter->key_cache_path, &u);

	if (k.k && !bkey_err(k)) {
@@ -2199,7 +2212,7 @@ static struct bkey_s_c __bch2_btree_iter_peek(struct btree_iter *iter, struct bp 
			goto out;

		}



		btree_path_set_should_be_locked(path);

		btree_path_set_should_be_locked(trans, path);



		k = btree_path_level_peek_all(trans->c, l, &iter->k);
@@ -2382,14 +2395,14 @@ struct bkey_s_c bch2_btree_iter_peek_upto(struct btree_iter *iter, struct bpos e 
				iter->flags & BTREE_ITER_intent,

				btree_iter_ip_allocated(iter));



	btree_path_set_should_be_locked(btree_iter_path(trans, iter));

	btree_path_set_should_be_locked(trans, btree_iter_path(trans, iter));

out_no_locked:

	if (iter->update_path) {

		ret = bch2_btree_path_relock(trans, trans->paths + iter->update_path, _THIS_IP_);

		if (unlikely(ret))

			k = bkey_s_c_err(ret);

		else

			btree_path_set_should_be_locked(trans->paths + iter->update_path);

			btree_path_set_should_be_locked(trans, trans->paths + iter->update_path);

	}



	if (!(iter->flags & BTREE_ITER_all_snapshots))
@@ -2511,6 +2524,7 @@ struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter) 
								iter->flags & BTREE_ITER_intent,

								_THIS_IP_);

					path = btree_iter_path(trans, iter);

					trace_btree_path_save_pos(trans, path, trans->paths + saved_path);

					saved_k = *k.k;

					saved_v = k.v;

				}
@@ -2527,7 +2541,7 @@ struct bkey_s_c bch2_btree_iter_peek_prev(struct btree_iter *iter) 
				continue;

			}



			btree_path_set_should_be_locked(path);

			btree_path_set_should_be_locked(trans, path);

			break;

		} else if (likely(!bpos_eq(path->l[0].b->data->min_key, POS_MIN))) {

			/* Advance to previous leaf node: */
@@ -2685,7 +2699,7 @@ struct bkey_s_c bch2_btree_iter_peek_slot(struct btree_iter *iter) 
		}

	}

out:

	btree_path_set_should_be_locked(btree_iter_path(trans, iter));

	btree_path_set_should_be_locked(trans, btree_iter_path(trans, iter));

out_no_locked:

	bch2_btree_iter_verify_entry_exit(iter);

	bch2_btree_iter_verify(iter);

fs/bcachefs/btree_iter.h

+2 −0
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ static inline void __btree_path_get(struct btree_trans *trans, struct btree_path 


	path->ref++;

	path->intent_ref += intent;

	trace_btree_path_get_ll(trans, path);

}



static inline bool __btree_path_put(struct btree_trans *trans, struct btree_path *path, bool intent)
@@ -39,6 +40,7 @@ static inline bool __btree_path_put(struct btree_trans *trans, struct btree_path 
	EBUG_ON(!path->ref);

	EBUG_ON(!path->intent_ref && intent);



	trace_btree_path_put_ll(trans, path);

	path->intent_ref -= intent;

	return --path->ref == 0;

}

fs/bcachefs/btree_locking.h

+5 −1
Original line number Diff line number Diff line
@@ -228,6 +228,9 @@ static inline int __btree_node_lock_nopath(struct btree_trans *trans, 
				 bch2_six_check_for_deadlock, trans, ip);

	WRITE_ONCE(trans->locking, NULL);

	WRITE_ONCE(trans->locking_wait.start_time, 0);



	if (!ret)

		trace_btree_path_lock(trans, _THIS_IP_, b);

	return ret;

}
@@ -400,12 +403,13 @@ static inline int bch2_btree_path_upgrade(struct btree_trans *trans, 


/* misc: */



static inline void btree_path_set_should_be_locked(struct btree_path *path)

static inline void btree_path_set_should_be_locked(struct btree_trans *trans, struct btree_path *path)

{

	EBUG_ON(!btree_node_locked(path, path->level));

	EBUG_ON(path->uptodate);



	path->should_be_locked = true;

	trace_btree_path_should_be_locked(trans, path);

}



static inline void __btree_path_set_level_up(struct btree_trans *trans,

fs/bcachefs/btree_update.c

+7 −3
Original line number Diff line number Diff line
@@ -374,7 +374,7 @@ static noinline int flush_new_cached_update(struct btree_trans *trans, 
	i->key_cache_already_flushed = true;

	i->flags |= BTREE_TRIGGER_norun;



	btree_path_set_should_be_locked(btree_path);

	btree_path_set_should_be_locked(trans, btree_path);

	ret = bch2_trans_update_by_path(trans, path_idx, i->k, flags, ip);

out:

	bch2_path_put(trans, path_idx, true);
@@ -422,7 +422,9 @@ bch2_trans_update_by_path(struct btree_trans *trans, btree_path_idx_t path_idx, 
			break;

	}



	if (!cmp && i < trans->updates + trans->nr_updates) {

	bool overwrite = !cmp && i < trans->updates + trans->nr_updates;



	if (overwrite) {

		EBUG_ON(i->insert_trigger_run || i->overwrite_trigger_run);



		bch2_path_put(trans, i->path, true);
@@ -451,6 +453,8 @@ bch2_trans_update_by_path(struct btree_trans *trans, btree_path_idx_t path_idx, 


	__btree_path_get(trans, trans->paths + i->path, true);



	trace_update_by_path(trans, path, i, overwrite);



	/*

	 * If a key is present in the key cache, it must also exist in the

	 * btree - this is necessary for cache coherency. When iterating over
@@ -498,7 +502,7 @@ static noinline int bch2_trans_update_get_key_cache(struct btree_trans *trans, 
			return btree_trans_restart(trans, BCH_ERR_transaction_restart_key_cache_raced);

		}



		btree_path_set_should_be_locked(trans->paths + iter->key_cache_path);

		btree_path_set_should_be_locked(trans, trans->paths + iter->key_cache_path);

	}



	return 0;