bcachefs: Improve trans_restart_mem_realloced tracepoint

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

fs/bcachefs/btree_iter.c

@@ -2111,11 +2111,14 @@ struct btree_iter *__bch2_trans_copy_iter(struct btree_trans *trans,
 	return iter;
 }
 
-static int bch2_trans_preload_mem(struct btree_trans *trans, size_t size)
+void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
 {
-	if (size > trans->mem_bytes) {
+	size_t new_top = trans->mem_top + size;
+	void *p;
+
+	if (new_top > trans->mem_bytes) {
 		size_t old_bytes = trans->mem_bytes;
-		size_t new_bytes = roundup_pow_of_two(size);
+		size_t new_bytes = roundup_pow_of_two(new_top);
 		void *new_mem;
 
 		WARN_ON_ONCE(new_bytes > BTREE_TRANS_MEM_MAX);
@@ -2128,29 +2131,17 @@ static int bch2_trans_preload_mem(struct btree_trans *trans, size_t size)
 		}
 
 		if (!new_mem)
-			return -ENOMEM;
+			return ERR_PTR(-ENOMEM);
 
 		trans->mem = new_mem;
 		trans->mem_bytes = new_bytes;
 
 		if (old_bytes) {
-			trace_trans_restart_mem_realloced(trans->ip, new_bytes);
-			return -EINTR;
+			trace_trans_restart_mem_realloced(trans->ip, _RET_IP_, new_bytes);
+			return ERR_PTR(-EINTR);
 		}
 	}
 
-	return 0;
-}
-
-void *bch2_trans_kmalloc(struct btree_trans *trans, size_t size)
-{
-	void *p;
-	int ret;
-
-	ret = bch2_trans_preload_mem(trans, trans->mem_top + size);
-	if (ret)
-		return ERR_PTR(ret);
-
 	p = trans->mem + trans->mem_top;
 	trans->mem_top += size;
 	return p;

fs/bcachefs/trace.h

@@ -627,38 +627,27 @@ TRACE_EVENT(trans_restart_would_deadlock,
 		  __entry->want_pos_snapshot)
 );
 
-TRACE_EVENT(trans_restart_iters_realloced,
-	TP_PROTO(unsigned long ip, unsigned nr),
-	TP_ARGS(ip, nr),
-
-	TP_STRUCT__entry(
-		__field(unsigned long,		ip	)
-		__field(unsigned,		nr	)
-	),
-
-	TP_fast_assign(
-		__entry->ip	= ip;
-		__entry->nr	= nr;
-	),
-
-	TP_printk("%pS nr %u", (void *) __entry->ip, __entry->nr)
-);
-
 TRACE_EVENT(trans_restart_mem_realloced,
-	TP_PROTO(unsigned long ip, unsigned long bytes),
-	TP_ARGS(ip, bytes),
+	TP_PROTO(unsigned long trans_ip, unsigned long caller_ip,
+		 unsigned long bytes),
+	TP_ARGS(trans_ip, caller_ip, bytes),
 
 	TP_STRUCT__entry(
-		__field(unsigned long,		ip	)
-		__field(unsigned long,		bytes	)
+		__field(unsigned long,		trans_ip	)
+		__field(unsigned long,		caller_ip	)
+		__field(unsigned long,		bytes		)
 	),
 
 	TP_fast_assign(
-		__entry->ip	= ip;
-		__entry->bytes	= bytes;
+		__entry->trans_ip	= trans_ip;
+		__entry->caller_ip	= caller_ip;
+		__entry->bytes		= bytes;
 	),
 
-	TP_printk("%pS bytes %lu", (void *) __entry->ip, __entry->bytes)
+	TP_printk("%pS %pS bytes %lu",
+		  (void *) __entry->trans_ip,
+		  (void *) __entry->caller_ip,
+		  __entry->bytes)
 );
 
 DEFINE_EVENT(transaction_restart,	trans_restart_journal_res_get,