On Sun, Dec 29, 2019 at 03:37:40PM +0100, Jiri Olsa wrote:
> When unwinding the stack we need to identify each
> address to successfully continue. Adding latch tree
> to keep trampolines for quick lookup during the
> unwind.
>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
...
> +bool is_bpf_trampoline(void *addr)
> +{
> + return latch_tree_find(addr, &tree, &tree_ops) != NULL;
> +}
> +
> struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
> {
> struct bpf_trampoline *tr;
> @@ -65,6 +98,7 @@ struct bpf_trampoline *bpf_trampoline_lookup(u64 key)
> for (i = 0; i < BPF_TRAMP_MAX; i++)
> INIT_HLIST_HEAD(&tr->progs_hlist[i]);
> tr->image = image;
> + latch_tree_insert(&tr->tnode, &tree, &tree_ops);
Thanks for the fix. I was thinking to apply it, but then realized that bpf
dispatcher logic has the same issue.
Could you generalize the fix for both?
May be bpf_jit_alloc_exec_page() can do latch_tree_insert() ?
and new version of bpf_jit_free_exec() is needed that will do latch_tree_erase().
Wdyt?
