Thanks for your reply. Using rte_hash iterate and delete keys is to free the related data's memory. There are two reasons why rte_hash_reset() is not properly: 1) the reset function just clear all keys, the key's related data are leaked. 2) In some cases, I don't need delete all keys. Just some selected keys and data are deleted and released.
Jerry. -----邮件原件----- 发件人: Honnappa Nagarahalli [mailto:honnappa.nagaraha...@arm.com] 发送时间: 2020年4月29日 4:46 收件人: Lilijun (Jerry) <jerry.lili...@huawei.com>; 'dev@dpdk.org' <dev@dpdk.org> 抄送: wangyunjian <wangyunj...@huawei.com>; xudingke <xudin...@huawei.com>; 'sta...@dpdk.org' <sta...@dpdk.org>; nd <n...@arm.com>; Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>; nd <n...@arm.com> 主题: RE: [dpdk-dev] [PATCH] lib/librte_hash: add rte_hash_del_key_fixed without compact <snip> Hi Jerry, Few questions inline. > Subject: [dpdk-dev] [PATCH] lib/librte_hash: add > rte_hash_del_key_fixed without compact > > The keys idx are stored in rte_hash main bucket key slots and extend > bucket key stots. > We iterate every no empty Keys in h->buckets and h->buckets_ext from > start to last. > When deleting keys the function __rte_hash_compact_ll() may move > last_bkt's key to previous bucket in order to compact extend bucket list. > If the previous bucket has been iterated, the moved key may be missed > for users. > Then those missed keys are leaked and rte_hash table can't be cleanup. > So we add a new API rte_hash_del_key_fixed() used in iterate loop to > avoid this bugs. > > --- > lib/librte_hash/rte_cuckoo_hash.c | 19 ++++++++++++++----- > lib/librte_hash/rte_hash.h | 5 +++++ > lib/librte_hash/rte_hash_version.map | 1 + > 3 files changed, 20 insertions(+), 5 deletions(-) > > diff --git a/lib/librte_hash/rte_cuckoo_hash.c > b/lib/librte_hash/rte_cuckoo_hash.c > index b52630b..2da3c1d 100644 > --- a/lib/librte_hash/rte_cuckoo_hash.c > +++ b/lib/librte_hash/rte_cuckoo_hash.c > @@ -1523,7 +1523,7 @@ search_and_remove(const struct rte_hash *h, > const void *key, > > static inline int32_t > __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key, > - hash_sig_t sig) > + hash_sig_t sig, uint8_t > compact) > { > uint32_t prim_bucket_idx, sec_bucket_idx; > struct rte_hash_bucket *prim_bkt, *sec_bkt, *prev_bkt, *last_bkt; @@ > -1541,7 +1541,8 @@ __rte_hash_del_key_with_hash(const struct rte_hash > *h, const void *key, > /* look for key in primary bucket */ > ret = search_and_remove(h, key, prim_bkt, short_sig, &pos); > if (ret != -1) { > - __rte_hash_compact_ll(h, prim_bkt, pos); > + if (compact) > + __rte_hash_compact_ll(h, prim_bkt, pos); > last_bkt = prim_bkt->next; > prev_bkt = prim_bkt; > goto return_bkt; > @@ -1553,7 +1554,8 @@ __rte_hash_del_key_with_hash(const struct > rte_hash *h, const void *key, > FOR_EACH_BUCKET(cur_bkt, sec_bkt) { > ret = search_and_remove(h, key, cur_bkt, short_sig, &pos); > if (ret != -1) { > - __rte_hash_compact_ll(h, cur_bkt, pos); > + if (compact) > + __rte_hash_compact_ll(h, cur_bkt, pos); > last_bkt = sec_bkt->next; > prev_bkt = sec_bkt; > goto return_bkt; > @@ -1607,14 +1609,21 @@ rte_hash_del_key_with_hash(const struct > rte_hash *h, > const void *key, hash_sig_t sig) > { > RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL); > - return __rte_hash_del_key_with_hash(h, key, sig); > + return __rte_hash_del_key_with_hash(h, key, sig, 1); > } > > int32_t > rte_hash_del_key(const struct rte_hash *h, const void *key) { > RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL); > - return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key)); > + return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key), > 1); > +} > + > +int32_t > +rte_hash_del_key_fixed(const struct rte_hash *h, const void *key) { > + RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL); > + return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key), > 0); > } > > int > diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h > index eceb365..9b71d8a 100644 > --- a/lib/librte_hash/rte_hash.h > +++ b/lib/librte_hash/rte_hash.h > @@ -297,6 +297,11 @@ rte_hash_add_key_with_hash(const struct rte_hash > *h, const void *key, hash_sig_t int32_t rte_hash_del_key(const > struct rte_hash *h, const void *key); > > + > +/* for without compact */ > +int32_t > +rte_hash_del_key_fixed(const struct rte_hash *h, const void *key); > + > /** > * Remove a key from an existing hash table. > * This operation is not multi-thread safe diff --git > a/lib/librte_hash/rte_hash_version.map > b/lib/librte_hash/rte_hash_version.map > index 30cc086..1941d17 100644 > --- a/lib/librte_hash/rte_hash_version.map > +++ b/lib/librte_hash/rte_hash_version.map > @@ -11,6 +11,7 @@ DPDK_20.0 { > rte_hash_count; > rte_hash_create; > rte_hash_del_key; > + rte_hash_del_key_fixed; > rte_hash_del_key_with_hash; > rte_hash_find_existing; > rte_hash_free; > -- > 2.19.1 > > -----邮件原件----- > 发件人: Lilijun (Jerry) > 发送时间: 2020年4月18日 18:00 > 收件人: 'dev@dpdk.org' <dev@dpdk.org>; 'sta...@dpdk.org' > <sta...@dpdk.org> > 主题: rte_hash bug: can't iterate all entries when deleting keys in > rte_hash iterate loop. > > Hi all, > > In my test, entries can't be cleanup in rte_hash table when > deleting keys in rte_hash iterate loop. The test steps: > 1. create a hash table table1 with limit 30000, ext bucket > enabled, and insert 30000 entries into this hash table. > 2. create a larger hash table table2 with limit 60000, , ext bucket > enabled. > 3. iterate all entries of table1 and insert them to the table2. > Insert new > 10000 entries to this table2. > 4. Then flush all entries from table2 by deleting keys in > rte_hash iterate loop. But there are still some keys leaked in table2. Is there any reason for flushing table2 in this manner? Is it possible to use 'rte_hash_reset' instead? > > From my analysis, the keys idx are stored in rte_hash main bucket > key slots and extend bucket key stots. > We iterate every no empty Keys in h->buckets and h->buckets_ext > from start to last. > When deleting keys the function __rte_hash_compact_ll() may move > last_bkt's key to previous bucket in order to compact extend bucket list. > If the previous bucket has been iterated, the moved key may be > missed for users. > Then those missed keys are leaked and rte_hash table can't be cleanup. > > Now I retry the iterate and delete keys, that can avoid this bug. > > Is there any ideas or solutions on this bug? Thanks. > > Jerry.
