bpf: udp: Get rid of st_bucket_done

Get rid of the st_bucket_done field to simplify UDP iterator state and
logic. Before, st_bucket_done could be false if bpf_iter_udp_batch
returned a partial batch; however, with the last patch ("bpf: udp: Make
sure iter->batch always contains a full bucket snapshot"),
st_bucket_done == true is equivalent to iter->cur_sk == iter->end_sk.

Signed-off-by: Jordan Rife <jordan@jrife.io>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 426a8b7c5cdec8e530f31bb6e55b5cb676aa0317..f2740802ee86630ee66b83700eb4f7b351a462a9 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -3420,7 +3420,6 @@ struct bpf_udp_iter_state {
        unsigned int max_sk;
        int offset;
        struct sock **batch;
-       bool st_bucket_done;
 };
 
 static int bpf_iter_udp_realloc_batch(struct bpf_udp_iter_state *iter,
@@ -3441,7 +3440,7 @@ static struct sock *bpf_iter_udp_batch(struct seq_file *seq)
        resume_offset = iter->offset;
 
        /* The current batch is done, so advance the bucket. */
-       if (iter->st_bucket_done)
+       if (iter->cur_sk == iter->end_sk)
                state->bucket++;
 
        udptable = udp_get_table_seq(seq, net);
@@ -3456,7 +3455,6 @@ again:
         */
        iter->cur_sk = 0;
        iter->end_sk = 0;
-       iter->st_bucket_done = true;
        batch_sks = 0;
 
        for (; state->bucket <= udptable->mask; state->bucket++) {
@@ -3619,8 +3617,10 @@ unlock:
 
 static void bpf_iter_udp_put_batch(struct bpf_udp_iter_state *iter)
 {
-       while (iter->cur_sk < iter->end_sk)
-               sock_put(iter->batch[iter->cur_sk++]);
+       unsigned int cur_sk = iter->cur_sk;
+
+       while (cur_sk < iter->end_sk)
+               sock_put(iter->batch[cur_sk++]);
 }
 
 static void bpf_iter_udp_seq_stop(struct seq_file *seq, void *v)
@@ -3636,10 +3636,8 @@ static void bpf_iter_udp_seq_stop(struct seq_file *seq, void *v)
                        (void)udp_prog_seq_show(prog, &meta, v, 0, 0);
        }
 
-       if (iter->cur_sk < iter->end_sk) {
+       if (iter->cur_sk < iter->end_sk)
                bpf_iter_udp_put_batch(iter);
-               iter->st_bucket_done = false;
-       }
 }
 
 static const struct seq_operations bpf_iter_udp_seq_ops = {
@@ -3925,6 +3923,8 @@ static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux)
        if (ret)
                bpf_iter_fini_seq_net(priv_data);
 
+       iter->state.bucket = -1;
+
        return ret;
 }