On Fri, Feb 11, 2022 at 7:21 AM Yonghong Song <yhs@xxxxxx> wrote:
>
> Previously, the following code in check_and_init_map_value()
> *(struct bpf_timer *)(dst + map->timer_off) =
> (struct bpf_timer){};
> can help generate bpf_timer definition in vmlinuxBTF.
> But previous patch replaced the above code with memset
For bisectability the order of the patches should be reverted then.
Otherwise we have a commit that will break selftests for no good
reason.
> so bpf_timer definition disappears from vmlinuxBTF.
> Let us emit the type explicitly so bpf program can continue
> to use it from vmlinux.h.
>
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
> ---
> kernel/bpf/helpers.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index 01cfdf40c838..66f9ed5093b2 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -16,6 +16,7 @@
> #include <linux/pid_namespace.h>
> #include <linux/proc_ns.h>
> #include <linux/security.h>
> +#include <linux/btf.h>
>
> #include "../../lib/kstrtox.h"
>
> @@ -1075,6 +1076,7 @@ static enum hrtimer_restart bpf_timer_cb(struct hrtimer *hrtimer)
> void *key;
> u32 idx;
>
> + BTF_TYPE_EMIT(struct bpf_timer);
> callback_fn = rcu_dereference_check(t->callback_fn, rcu_read_lock_bh_held());
> if (!callback_fn)
> goto out;
> --
> 2.30.2
>
