| Message ID | 20210117042224.17839-1-xiyou.wangcong@gmail.com |
|---|---|
| Headers | show |
| Series | bpf: introduce timeout hash map | expand |
On Sat, Jan 16, 2021 at 8:22 PM Cong Wang <xiyou.wangcong@gmail.com> wrote: > +static void htab_gc(struct work_struct *work) > +{ > + struct htab_elem *e, *tmp; > + struct llist_node *lhead; > + struct bpf_htab *htab; > + int i, count; > + > + htab = container_of(work, struct bpf_htab, gc_work.work); > + lhead = llist_del_all(&htab->gc_list); > + > + llist_for_each_entry_safe(e, tmp, lhead, gc_node) { > + unsigned long flags; > + struct bucket *b; > + u32 hash; > + > + hash = e->hash; > + b = __select_bucket(htab, hash); > + if (htab_lock_bucket(htab, b, hash, &flags)) > + continue; > + hlist_nulls_del_rcu(&e->hash_node); > + atomic_set(&e->pending, 0); > + free_htab_elem(htab, e); > + htab_unlock_bucket(htab, b, hash, flags); > + > + cond_resched(); > + } > + > + for (count = 0, i = 0; i < htab->n_buckets; i++) { I just realized a followup fix is not folded into this patch, I actually added a timestamp check here to avoid scanning the whole table more frequently than once per second. It is clearly my mistake to miss it when formatting this patchset. I will send v5 after waiting for other feedback. Thanks!
From: Cong Wang <cong.wang@bytedance.com> This patchset introduces a new eBPF hash map whose elements have timeouts. Patch 1 is the implementation of timeout map, patch 2 adds some test cases for timeout map in test_maps, and patch 3 adds a test case in map ptr test. Please check each patch description for more details. --- v4: merge gc_work into gc_idle_work to avoid a nasty race condition fix a potential use-after-free add one more test case improve comments and update changelog v3: move gc list from bucket to elem reuse lru_node in struct htab_elem drop patches which are no longer necessary fix delete path add a test case for delete path add parallel test cases change timeout to ms drop batch ops v2: fix hashmap ptr test add a test case in map ptr test factor out htab_timeout_map_alloc() Cong Wang (3): bpf: introduce timeout hash map selftests/bpf: add test cases for bpf timeout map selftests/bpf: add timeout map check in map_ptr tests include/linux/bpf_types.h | 1 + include/uapi/linux/bpf.h | 5 +- kernel/bpf/hashtab.c | 239 +++++++++++++++++- kernel/bpf/syscall.c | 3 +- tools/include/uapi/linux/bpf.h | 1 + .../selftests/bpf/progs/map_ptr_kern.c | 20 ++ tools/testing/selftests/bpf/test_maps.c | 47 ++++ 7 files changed, 307 insertions(+), 9 deletions(-)