bpf: Move ksym_tnode to bpf_ksym

Moving ksym_tnode list node to 'struct bpf_ksym' object, so the symbol itself can be chained and used in other objects like bpf_trampoline and bpf_dispatcher. We need bpf_ksym object to be linked both in bpf_kallsyms via lnode for /proc/kallsyms and in bpf_tree via tnode for bpf address lookup functions like __bpf_address_lookup or bpf_prog_kallsyms_find.

Jiri Olsa committed 6 years ago

Commit ca4424c1 parent ecb60d12 files · +11 −15Browse files

Unified · Split

2 files

include/linux/bpf.h +1 −1
kernel/bpf/core.c +10 −14

include/linux/bpf.h+1−1

 	unsigned long		 end;
 	char			 name[KSYM_NAME_LEN];
 	struct list_head	 lnode;
+	struct latch_tree_node	 tnode;
 };
 enum bpf_tramp_prog_type {
 	void *jit_data; /* JIT specific data. arch dependent */
 	struct bpf_jit_poke_descriptor *poke_tab;
 	u32 size_poke_tab;
-	struct latch_tree_node ksym_tnode;
 	struct bpf_ksym ksym;
 	const struct bpf_prog_ops *ops;
 	struct bpf_map **used_maps;

kernel/bpf/core.c+10−14

 		*sym = 0;
 }
-static __always_inline unsigned long
+static unsigned long bpf_get_ksym_start(struct latch_tree_node *n)
-bpf_get_prog_addr_start(struct latch_tree_node *n)
 {
-	const struct bpf_prog_aux *aux;
+	return container_of(n, struct bpf_ksym, tnode)->start;
-	aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
-	return aux->ksym.start;
 }
 static __always_inline bool bpf_tree_less(struct latch_tree_node *a,
 					  struct latch_tree_node *b)
 {
-	return bpf_get_prog_addr_start(a) < bpf_get_prog_addr_start(b);
+	return bpf_get_ksym_start(a) < bpf_get_ksym_start(b);
 }
 static __always_inline int bpf_tree_comp(void *key, struct latch_tree_node *n)
 {
 	unsigned long val = (unsigned long)key;
-	const struct bpf_prog_aux *aux;
+	const struct bpf_ksym *ksym;
-	aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
+	ksym = container_of(n, struct bpf_ksym, tnode);
-	if (val < aux->ksym.start)
+	if (val < ksym->start)
 		return -1;
-	if (val >= aux->ksym.end)
+	if (val >= ksym->end)
 		return  1;
 	return 0;
 {
 	WARN_ON_ONCE(!list_empty(&aux->ksym.lnode));
 	list_add_tail_rcu(&aux->ksym.lnode, &bpf_kallsyms);
-	latch_tree_insert(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
+	latch_tree_insert(&aux->ksym.tnode, &bpf_tree, &bpf_tree_ops);
 }
 static void bpf_prog_ksym_node_del(struct bpf_prog_aux *aux)
 	if (list_empty(&aux->ksym.lnode))
 		return;
-	latch_tree_erase(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
+	latch_tree_erase(&aux->ksym.tnode, &bpf_tree, &bpf_tree_ops);
 	list_del_rcu(&aux->ksym.lnode);
 }
 	n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops);
 	return n ?
-	       container_of(n, struct bpf_prog_aux, ksym_tnode)->prog :
+	       container_of(n, struct bpf_prog_aux, ksym.tnode)->prog :
 	       NULL;
 }