bcachefs: Debug params are now static_keys

We'd like users to be able to debug without building custom kernels, so
this will help us get rid of CONFIG_BCACHEFS_DEBUG, at least for most
things.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

16 files changed, 69 insertions, 39 deletions

diff --git a/fs/bcachefs/backpointers.c b/fs/bcachefs/backpointers.c
index 631d4d24d78f..bdf524b465fa 100644
--- a/fs/bcachefs/backpointers.c
+++ b/fs/bcachefs/backpointers.c
@@ -182,7 +182,7 @@ err:
 
 static int bch2_backpointer_del(struct btree_trans *trans, struct bpos pos)
 {
-	return (likely(!bch2_backpointers_no_use_write_buffer)
+	return (!static_branch_unlikely(&bch2_backpointers_no_use_write_buffer)
 		? bch2_btree_delete_at_buffered(trans, BTREE_ID_backpointers, pos)
 		: bch2_btree_delete(trans, BTREE_ID_backpointers, pos, 0)) ?:
 		 bch2_trans_commit(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc);
@@ -192,7 +192,7 @@ static inline int bch2_backpointers_maybe_flush(struct btree_trans *trans,
 					 struct bkey_s_c visiting_k,
 					 struct bkey_buf *last_flushed)
 {
-	return likely(!bch2_backpointers_no_use_write_buffer)
+	return !static_branch_unlikely(&bch2_backpointers_no_use_write_buffer)
 		? bch2_btree_write_buffer_maybe_flush(trans, visiting_k, last_flushed)
 		: 0;
 }
diff --git a/fs/bcachefs/backpointers.h b/fs/bcachefs/backpointers.h
index c72707ee9d42..f57098c32143 100644
--- a/fs/bcachefs/backpointers.h
+++ b/fs/bcachefs/backpointers.h
@@ -102,7 +102,7 @@ static inline int bch2_bucket_backpointer_mod(struct btree_trans *trans,
 				struct bkey_i_backpointer *bp,
 				bool insert)
 {
-	if (unlikely(bch2_backpointers_no_use_write_buffer))
+	if (static_branch_unlikely(&bch2_backpointers_no_use_write_buffer))
 		return bch2_bucket_backpointer_mod_nowritebuffer(trans, orig_k, bp, insert);
 
 	if (!insert) {
diff --git a/fs/bcachefs/bcachefs.h b/fs/bcachefs/bcachefs.h
index 5392a0ec6439..46976409f733 100644
--- a/fs/bcachefs/bcachefs.h
+++ b/fs/bcachefs/bcachefs.h
@@ -439,16 +439,10 @@ do {									\
 #define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS()
 #endif
 
-#define BCH_DEBUG_PARAM(name, description) extern bool bch2_##name;
-BCH_DEBUG_PARAMS()
+#define BCH_DEBUG_PARAM(name, description) extern struct static_key_false bch2_##name;
+BCH_DEBUG_PARAMS_ALL()
 #undef BCH_DEBUG_PARAM
 
-#ifndef CONFIG_BCACHEFS_DEBUG
-#define BCH_DEBUG_PARAM(name, description) static const __maybe_unused bool bch2_##name;
-BCH_DEBUG_PARAMS_DEBUG()
-#undef BCH_DEBUG_PARAM
-#endif
-
 #define BCH_TIME_STATS()			\
 	x(btree_node_mem_alloc)			\
 	x(btree_node_split)			\
diff --git a/fs/bcachefs/bkey.h b/fs/bcachefs/bkey.h
index 082632905649..b33356982460 100644
--- a/fs/bcachefs/bkey.h
+++ b/fs/bcachefs/bkey.h
@@ -399,7 +399,7 @@ __bkey_unpack_key_format_checked(const struct btree *b,
 		unpack_fn(dst, src);
 
 		if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
-		    bch2_expensive_debug_checks) {
+		    static_branch_unlikely(&bch2_expensive_debug_checks)) {
 			struct bkey dst2 = __bch2_bkey_unpack_key(&b->format, src);
 
 			BUG_ON(memcmp(dst, &dst2, sizeof(*dst)));
diff --git a/fs/bcachefs/bkey_methods.c b/fs/bcachefs/bkey_methods.c
index 00d05ccfaf73..fcd8c82cba4f 100644
--- a/fs/bcachefs/bkey_methods.c
+++ b/fs/bcachefs/bkey_methods.c
@@ -356,7 +356,7 @@ bool bch2_bkey_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r)
 	return ops->key_merge &&
 		bch2_bkey_maybe_mergable(l.k, r.k) &&
 		(u64) l.k->size + r.k->size <= KEY_SIZE_MAX &&
-		!bch2_key_merging_disabled &&
+		!static_branch_unlikely(&bch2_key_merging_disabled) &&
 		ops->key_merge(c, l, r);
 }
 
diff --git a/fs/bcachefs/bset.c b/fs/bcachefs/bset.c
index 9a4a83d6fd2d..7d2004a47fe6 100644
--- a/fs/bcachefs/bset.c
+++ b/fs/bcachefs/bset.c
@@ -501,7 +501,7 @@ static void bch2_bset_verify_rw_aux_tree(struct btree *b,
 	struct bkey_packed *k = btree_bkey_first(b, t);
 	unsigned j = 0;
 
-	if (!bch2_expensive_debug_checks)
+	if (!static_branch_unlikely(&bch2_expensive_debug_checks))
 		return;
 
 	BUG_ON(bset_has_ro_aux_tree(t));
@@ -869,7 +869,7 @@ struct bkey_packed *bch2_bkey_prev_filter(struct btree *b,
 		k = p;
 	}
 
-	if (bch2_expensive_debug_checks) {
+	if (static_branch_unlikely(&bch2_expensive_debug_checks)) {
 		BUG_ON(ret >= orig_k);
 
 		for (i = ret
@@ -1195,7 +1195,7 @@ struct bkey_packed *bch2_bset_search_linear(struct btree *b,
 		       bkey_iter_pos_cmp(b, m, search) < 0)
 			m = bkey_p_next(m);
 
-	if (bch2_expensive_debug_checks) {
+	if (static_branch_unlikely(&bch2_expensive_debug_checks)) {
 		struct bkey_packed *prev = bch2_bkey_prev_all(b, t, m);
 
 		BUG_ON(prev &&
@@ -1435,7 +1435,7 @@ static inline void __bch2_btree_node_iter_advance(struct btree_node_iter *iter,
 void bch2_btree_node_iter_advance(struct btree_node_iter *iter,
 				  struct btree *b)
 {
-	if (bch2_expensive_debug_checks) {
+	if (static_branch_unlikely(&bch2_expensive_debug_checks)) {
 		bch2_btree_node_iter_verify(iter, b);
 		bch2_btree_node_iter_next_check(iter, b);
 	}
@@ -1453,7 +1453,7 @@ struct bkey_packed *bch2_btree_node_iter_prev_all(struct btree_node_iter *iter,
 	struct btree_node_iter_set *set;
 	unsigned end = 0;
 
-	if (bch2_expensive_debug_checks)
+	if (static_branch_unlikely(&bch2_expensive_debug_checks))
 		bch2_btree_node_iter_verify(iter, b);
 
 	for_each_bset(b, t) {
@@ -1489,7 +1489,7 @@ found:
 	iter->data[0].k = __btree_node_key_to_offset(b, prev);
 	iter->data[0].end = end;
 
-	if (bch2_expensive_debug_checks)
+	if (static_branch_unlikely(&bch2_expensive_debug_checks))
 		bch2_btree_node_iter_verify(iter, b);
 	return prev;
 }
diff --git a/fs/bcachefs/bset.h b/fs/bcachefs/bset.h
index 6953d55b72cc..f5b7fda537ea 100644
--- a/fs/bcachefs/bset.h
+++ b/fs/bcachefs/bset.h
@@ -537,7 +537,7 @@ static inline void bch2_verify_insert_pos(struct btree *b,
 
 static inline void bch2_verify_btree_nr_keys(struct btree *b)
 {
-	if (bch2_debug_check_btree_accounting)
+	if (static_branch_unlikely(&bch2_debug_check_btree_accounting))
 		__bch2_verify_btree_nr_keys(b);
 }
 
diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c
index e48089252bb9..2fd58b08a54d 100644
--- a/fs/bcachefs/btree_cache.c
+++ b/fs/bcachefs/btree_cache.c
@@ -377,7 +377,7 @@ static int __btree_node_reclaim_checks(struct bch_fs *c, struct btree *b,
 			 * - unless btree verify mode is enabled, since it runs out of
 			 * the post write cleanup:
 			 */
-			if (bch2_verify_btree_ondisk)
+			if (static_branch_unlikely(&bch2_verify_btree_ondisk))
 				bch2_btree_node_write(c, b, SIX_LOCK_intent,
 						      BTREE_WRITE_cache_reclaim);
 			else
@@ -473,7 +473,7 @@ static unsigned long bch2_btree_cache_scan(struct shrinker *shrink,
 	unsigned long ret = SHRINK_STOP;
 	bool trigger_writes = atomic_long_read(&bc->nr_dirty) + nr >= list->nr * 3 / 4;
 
-	if (bch2_btree_shrinker_disabled)
+	if (static_branch_unlikely(&bch2_btree_shrinker_disabled))
 		return SHRINK_STOP;
 
 	mutex_lock(&bc->lock);
@@ -569,7 +569,7 @@ static unsigned long bch2_btree_cache_count(struct shrinker *shrink,
 {
 	struct btree_cache_list *list = shrink->private_data;
 
-	if (bch2_btree_shrinker_disabled)
+	if (static_branch_unlikely(&bch2_btree_shrinker_disabled))
 		return 0;
 
 	return btree_cache_can_free(list);
diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index dd08ec080313..91b6395421df 100644
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -619,7 +619,7 @@ static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
 	deleted.p = k.k->p;
 
 	if (initial) {
-		BUG_ON(bch2_journal_seq_verify &&
+		BUG_ON(static_branch_unlikely(&bch2_journal_seq_verify) &&
 		       k.k->bversion.lo > atomic64_read(&c->journal.seq));
 
 		if (fsck_err_on(btree_id != BTREE_ID_accounting &&
diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index e079e12adf86..d9adc4f5ba3d 100644
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -1296,7 +1296,7 @@ int bch2_btree_node_read_done(struct bch_fs *c, struct bch_dev *ca,
 
 		ret = btree_node_bkey_val_validate(c, b, u.s_c, READ);
 		if (ret == -BCH_ERR_fsck_delete_bkey ||
-		    (bch2_inject_invalid_keys &&
+		    (static_branch_unlikely(&bch2_inject_invalid_keys) &&
 		     !bversion_cmp(u.k->bversion, MAX_VERSION))) {
 			btree_keys_account_key_drop(&b->nr, 0, k);
 
@@ -1758,7 +1758,7 @@ void bch2_btree_node_read(struct btree_trans *trans, struct btree *b,
 
 	trace_and_count(c, btree_node_read, trans, b);
 
-	if (bch2_verify_all_btree_replicas &&
+	if (static_branch_unlikely(&bch2_verify_all_btree_replicas) &&
 	    !btree_node_read_all_replicas(c, b, sync))
 		return;
 
diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index bd3a0bc07511..be62958cdb9a 100644
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -147,7 +147,7 @@ static void bch2_btree_path_verify_level(struct btree_trans *trans,
 	struct printbuf buf3 = PRINTBUF;
 	const char *msg;
 
-	if (!bch2_debug_check_iterators)
+	if (!static_branch_unlikely(&bch2_debug_check_iterators))
 		return;
 
 	l	= &path->l[level];
@@ -281,7 +281,7 @@ static int bch2_btree_iter_verify_ret(struct btree_trans *trans,
 	struct bkey_s_c prev;
 	int ret = 0;
 
-	if (!bch2_debug_check_iterators)
+	if (!static_branch_unlikely(&bch2_debug_check_iterators))
 		return 0;
 
 	if (!(iter->flags & BTREE_ITER_filter_snapshots))
@@ -523,7 +523,7 @@ void bch2_btree_node_iter_fix(struct btree_trans *trans,
 		__bch2_btree_node_iter_fix(path, b, node_iter, t,
 					   where, clobber_u64s, new_u64s);
 
-		if (bch2_debug_check_iterators)
+		if (static_branch_unlikely(&bch2_debug_check_iterators))
 			bch2_btree_node_iter_verify(node_iter, b);
 	}
 
@@ -2929,7 +2929,7 @@ static void btree_trans_verify_sorted(struct btree_trans *trans)
 	struct btree_path *path, *prev = NULL;
 	struct trans_for_each_path_inorder_iter iter;
 
-	if (!bch2_debug_check_iterators)
+	if (!static_branch_unlikely(&bch2_debug_check_iterators))
 		return;
 
 	trans_for_each_path_inorder(trans, path, iter) {
diff --git a/fs/bcachefs/btree_trans_commit.c b/fs/bcachefs/btree_trans_commit.c
index cdde769e7da3..7e17df1df7f1 100644
--- a/fs/bcachefs/btree_trans_commit.c
+++ b/fs/bcachefs/btree_trans_commit.c
@@ -647,10 +647,10 @@ bch2_trans_commit_write_locked(struct btree_trans *trans, unsigned flags,
 
 	if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
 	    !(flags & BCH_TRANS_COMMIT_no_journal_res)) {
-		if (bch2_journal_seq_verify)
+		if (static_branch_unlikely(&bch2_journal_seq_verify))
 			trans_for_each_update(trans, i)
 				i->k->k.bversion.lo = trans->journal_res.seq;
-		else if (bch2_inject_invalid_keys)
+		else if (static_branch_unlikely(&bch2_inject_invalid_keys))
 			trans_for_each_update(trans, i)
 				i->k->k.bversion = MAX_VERSION;
 	}
diff --git a/fs/bcachefs/btree_update_interior.h b/fs/bcachefs/btree_update_interior.h
index ff9b95aac554..7fe793788a79 100644
--- a/fs/bcachefs/btree_update_interior.h
+++ b/fs/bcachefs/btree_update_interior.h
@@ -144,7 +144,7 @@ static inline int bch2_foreground_maybe_merge_sibling(struct btree_trans *trans,
 
 	EBUG_ON(!btree_node_locked(path, level));
 
-	if (bch2_btree_node_merging_disabled)
+	if (static_branch_unlikely(&bch2_btree_node_merging_disabled))
 		return 0;
 
 	b = path->l[level].b;
diff --git a/fs/bcachefs/debug.h b/fs/bcachefs/debug.h
index 52dbea736709..d88b1194b8ac 100644
--- a/fs/bcachefs/debug.h
+++ b/fs/bcachefs/debug.h
@@ -14,7 +14,7 @@ void bch2_btree_node_ondisk_to_text(struct printbuf *, struct bch_fs *,
 
 static inline void bch2_btree_verify(struct bch_fs *c, struct btree *b)
 {
-	if (bch2_verify_btree_ondisk)
+	if (static_branch_unlikely(&bch2_verify_btree_ondisk))
 		__bch2_btree_verify(c, b);
 }
 
diff --git a/fs/bcachefs/extents.c b/fs/bcachefs/extents.c
index d3af841e48ef..1ac9897f189d 100644
--- a/fs/bcachefs/extents.c
+++ b/fs/bcachefs/extents.c
@@ -164,7 +164,7 @@ static inline bool ptr_better(struct bch_fs *c,
 	if (unlikely(failed_delta))
 		return failed_delta < 0;
 
-	if (unlikely(bch2_force_reconstruct_read))
+	if (static_branch_unlikely(&bch2_force_reconstruct_read))
 		return p1.do_ec_reconstruct > p2.do_ec_reconstruct;
 
 	if (unlikely(p1.do_ec_reconstruct || p2.do_ec_reconstruct))
@@ -259,7 +259,7 @@ int bch2_bkey_pick_read_device(struct bch_fs *c, struct bkey_s_c k,
 			p.do_ec_reconstruct = true;
 		}
 
-		if (bch2_force_reconstruct_read && p.has_ec)
+		if (static_branch_unlikely(&bch2_force_reconstruct_read) && p.has_ec)
 			p.do_ec_reconstruct = true;
 
 		u64 p_latency = dev_latency(ca);
diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 95ed5ab541d3..8125c6804bd5 100644
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -2430,9 +2430,45 @@ err:
 	return -ENOMEM;
 }
 
-#define BCH_DEBUG_PARAM(name, description)			\
-	bool bch2_##name;					\
-	module_param_named(name, bch2_##name, bool, 0644);	\
+#define BCH_DEBUG_PARAM(name, description) DEFINE_STATIC_KEY_FALSE(bch2_##name);
+BCH_DEBUG_PARAMS_ALL()
+#undef BCH_DEBUG_PARAM
+
+static int bch2_param_set_static_key_t(const char *val, const struct kernel_param *kp)
+{
+	/* Match bool exactly, by re-using it. */
+	struct static_key *key = kp->arg;
+	struct kernel_param boolkp = *kp;
+	bool v;
+	int ret;
+
+	boolkp.arg = &v;
+
+	ret = param_set_bool(val, &boolkp);
+	if (ret)
+		return ret;
+	if (v)
+		static_key_enable(key);
+	else
+		static_key_disable(key);
+	return 0;
+}
+
+static int bch2_param_get_static_key_t(char *buffer, const struct kernel_param *kp)
+{
+	struct static_key *key = kp->arg;
+	return sprintf(buffer, "%c\n", static_key_enabled(key) ? 'N' : 'Y');
+}
+
+static const struct kernel_param_ops bch2_param_ops_static_key_t = {
+	.flags = KERNEL_PARAM_OPS_FL_NOARG,
+	.set = bch2_param_set_static_key_t,
+	.get = bch2_param_get_static_key_t,
+};
+
+#define BCH_DEBUG_PARAM(name, description)				\
+	module_param_cb(name, &bch2_param_ops_static_key_t, &bch2_##name.key, 0644);\
+	__MODULE_PARM_TYPE(name, "static_key_t");			\
 	MODULE_PARM_DESC(name, description);
 BCH_DEBUG_PARAMS()
 #undef BCH_DEBUG_PARAM