[PATCH v9 net-next 11/15] lwt: Don't disable migration prio invoking BPF.

Sebastian Andrzej Siewior
2024-06-20T13:27:36Z

There is no need to explicitly disable migration if bottom halves are
also disabled. Disabling BH implies disabling migration.

Remove migrate_disable() and rely solely on disabling BH to remain on
the same CPU.

Cc: bpf@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
net/core/lwt_bpf.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c
index 4a0797f0a154b..a94943681e5aa 100644
--- a/net/core/lwt_bpf.c
+++ b/net/core/lwt_bpf.c
@@ -40,10 +40,9 @@ static int run_lwt_bpf(struct sk_buff *skb, struct bpf_lwt_prog *lwt,
{
int ret;

- /* Migration disable and BH disable are needed to protect per-cpu
- * redirect_info between BPF prog and skb_do_redirect().
+ /* Disabling BH is needed to protect per-CPU bpf_redirect_info between
+ * BPF prog and skb_do_redirect().
*/
- migrate_disable();
local_bh_disable();
bpf_compute_data_pointers(skb);
ret = bpf_prog_run_save_cb(lwt->prog, skb);
@@ -78,7 +77,6 @@ static int run_lwt_bpf(struct sk_buff *skb, struct bpf_lwt_prog *lwt,
}

local_bh_enable();
- migrate_enable();

return ret;
}
--
2.45.2