[dpdk-dev] hash: added rte_hash_keys to extract all keys
Commit Message
I added a function which extracts all the configured keys in a hash map.
This is good to have when debugging and printing data store in hash
maps.
Signed-off-by: Tomas Vestelind <tomas.vestelind@gmail.com>
---
lib/librte_hash/rte_hash.c | 26 ++++++++++++++++++++++++++
lib/librte_hash/rte_hash.h | 15 +++++++++++++++
2 files changed, 41 insertions(+)
Comments
2014-08-12 23:47, Tomas Vestelind:
> I added a function which extracts all the configured keys in a hash map.
> This is good to have when debugging and printing data store in hash
> maps.
Someone to review this patch, please?
(and the other one for rte_hash_clear)
On Tue, 12 Aug 2014 23:47:33 +0200
Tomas Vestelind <tomas.vestelind@gmail.com> wrote:
> I added a function which extracts all the configured keys in a hash map.
> This is good to have when debugging and printing data store in hash
> maps.
>
> Signed-off-by: Tomas Vestelind <tomas.vestelind@gmail.com>
> ---
> lib/librte_hash/rte_hash.c | 26 ++++++++++++++++++++++++++
> lib/librte_hash/rte_hash.h | 15 +++++++++++++++
> 2 files changed, 41 insertions(+)
>
> diff --git a/lib/librte_hash/rte_hash.c b/lib/librte_hash/rte_hash.c
> index d02b6b4..2108c4f 100644
> --- a/lib/librte_hash/rte_hash.c
> +++ b/lib/librte_hash/rte_hash.c
> @@ -481,3 +481,29 @@ rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
>
> return 0;
> }
> +
> +unsigned int
> +rte_hash_keys(const struct rte_hash *h, void *keys)
> +{
> + unsigned int found_keys = 0;
> + unsigned int bucket, entry;
> +
> + /* Go through each bucket and all its entries */
> + for (bucket = 0; bucket < h->num_buckets; bucket++) {
> + const hash_sig_t *sig = get_sig_tbl_bucket(h, bucket);
> +
> + for (entry = 0; entry < h->bucket_entries; entry++) {
> + /* If the signature is valid, find and save the corresponding key */
> + if (sig[entry] != NULL_SIGNATURE) {
> + uint8_t *key_bucket = get_key_tbl_bucket(h, bucket);
> + void *key = get_key_from_bucket(h, key_bucket, entry);
> + rte_memcpy(keys, key, h->key_len);
> +
> + keys = (uint8_t* )keys + h->key_len;
> + found_keys++;
> + }
> + }
> + }
> +
> + return found_keys;
> +}
> diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h
> index 2ecaf1a..e0fb28f 100644
> --- a/lib/librte_hash/rte_hash.h
> +++ b/lib/librte_hash/rte_hash.h
> @@ -303,6 +303,21 @@ rte_hash_hash(const struct rte_hash *h, const void *key)
> int
> rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
> uint32_t num_keys, int32_t *positions);
> +
> +/**
> + * Copy the hash table keys to the supplied list of keys.
> + * This operation is multi-thread safe.
> + *
> + * @param h
> + * Hash table to look in.
> + * @param keys
> + * A pointer to a list of where keys will be written.
> + * Must be large enough to fit a potentially full hash map.
> + * @return
> + * The number of found keys.
> + */
> +unsigned int
> +rte_hash_keys(const struct rte_hash *h, void *keys);
> #ifdef __cplusplus
> }
> #endif
Please indent with tabs not spaces.
Using rte_memcpy() is no better than just using memcpy.
Please put blank line after declartions.
Writing code with continue makes it easier?
for (entry = 0; entry < h->bucket_entries; entry++) {
/* If the signature is valid, find and save the corresponding key */
if (sig[entry] == NULL_SIGNATURE
continue;
Hi Tomas,
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Tomas Vestelind
> Sent: Tuesday, August 12, 2014 10:48 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH] hash: added rte_hash_keys to extract all keys
>
> I added a function which extracts all the configured keys in a hash map.
> This is good to have when debugging and printing data store in hash
> maps.
>
> Signed-off-by: Tomas Vestelind <tomas.vestelind@gmail.com>
> ---
> lib/librte_hash/rte_hash.c | 26 ++++++++++++++++++++++++++
> lib/librte_hash/rte_hash.h | 15 +++++++++++++++
> 2 files changed, 41 insertions(+)
>
> diff --git a/lib/librte_hash/rte_hash.c b/lib/librte_hash/rte_hash.c
> index d02b6b4..2108c4f 100644
> --- a/lib/librte_hash/rte_hash.c
> +++ b/lib/librte_hash/rte_hash.c
> @@ -481,3 +481,29 @@ rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
>
> return 0;
> }
> +
> +unsigned int
> +rte_hash_keys(const struct rte_hash *h, void *keys)
> +{
> + unsigned int found_keys = 0;
> + unsigned int bucket, entry;
> +
> + /* Go through each bucket and all its entries */
> + for (bucket = 0; bucket < h->num_buckets; bucket++) {
> + const hash_sig_t *sig = get_sig_tbl_bucket(h, bucket);
> +
> + for (entry = 0; entry < h->bucket_entries; entry++) {
> + /* If the signature is valid, find and save the corresponding key */
> + if (sig[entry] != NULL_SIGNATURE) {
> + uint8_t *key_bucket = get_key_tbl_bucket(h, bucket);
> + void *key = get_key_from_bucket(h, key_bucket, entry);
> + rte_memcpy(keys, key, h->key_len);
> +
> + keys = (uint8_t* )keys + h->key_len;
> + found_keys++;
> + }
> + }
> + }
I suppose we need to add one extra parameter: keys_size (size of the buffer provided) and inside the loop check that we wouldn't go beyond it.
Also it would probably helpful to have a function that would return to the user size of buffer needed to sore all keys from the hash.
What you probably can do: implement a function that would iterate over all elements in the hash table and for each of them call a callback (taken as an argument).
Then all these functions and rte_hash_clear() could be implemented on top of it.
Something like:
typedef int (*rte_hash_elem_iter_t)(const struct rte_hash*hash, const void *key, void *user_arg);
void
rte_hash_elem_iterate(const struct rte_hash *h, rte_hash_key_elem_t iter, void *arg)
{
...
}
About rte_hash_clear(const struct rte_hash *h) - can't we just do memset(h->sig_tbl, NULL_SIGNATURE, sig_tbl_size);?
BTW, why it is pointer to the const strucuture if we modifying it?
> +
> + return found_keys;
> +}
> diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h
> index 2ecaf1a..e0fb28f 100644
> --- a/lib/librte_hash/rte_hash.h
> +++ b/lib/librte_hash/rte_hash.h
> @@ -303,6 +303,21 @@ rte_hash_hash(const struct rte_hash *h, const void *key)
> int
> rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
> uint32_t num_keys, int32_t *positions);
> +
> +/**
> + * Copy the hash table keys to the supplied list of keys.
> + * This operation is multi-thread safe.
> + *
> + * @param h
> + * Hash table to look in.
> + * @param keys
> + * A pointer to a list of where keys will be written.
> + * Must be large enough to fit a potentially full hash map.
> + * @return
> + * The number of found keys.
> + */
> +unsigned int
> +rte_hash_keys(const struct rte_hash *h, void *keys);
> #ifdef __cplusplus
> }
> #endif
> --
> 1.7.10.4
We implemented a more general hash iterator, thought the patch was already submitted.
Hello!
If there's already an iterator then I guess this patch is superfluous.
I tried searching for it among the e-mails but I can find it, can
someone point me to it?
If you still think this has some values I will take the given feedback
and make corrections.
Best regards,
Tomas Vestelind
ps. Stephen sorry for the extra mail, I forgot to cc the correct
people in the first one.
On 8/29/14, Stephen Hemminger <stephen@networkplumber.org> wrote:
> We implemented a more general hash iterator, thought the patch was already
> submitted.
>
@@ -481,3 +481,29 @@ rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
return 0;
}
+
+unsigned int
+rte_hash_keys(const struct rte_hash *h, void *keys)
+{
+ unsigned int found_keys = 0;
+ unsigned int bucket, entry;
+
+ /* Go through each bucket and all its entries */
+ for (bucket = 0; bucket < h->num_buckets; bucket++) {
+ const hash_sig_t *sig = get_sig_tbl_bucket(h, bucket);
+
+ for (entry = 0; entry < h->bucket_entries; entry++) {
+ /* If the signature is valid, find and save the corresponding key */
+ if (sig[entry] != NULL_SIGNATURE) {
+ uint8_t *key_bucket = get_key_tbl_bucket(h, bucket);
+ void *key = get_key_from_bucket(h, key_bucket, entry);
+ rte_memcpy(keys, key, h->key_len);
+
+ keys = (uint8_t* )keys + h->key_len;
+ found_keys++;
+ }
+ }
+ }
+
+ return found_keys;
+}
@@ -303,6 +303,21 @@ rte_hash_hash(const struct rte_hash *h, const void *key)
int
rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
uint32_t num_keys, int32_t *positions);
+
+/**
+ * Copy the hash table keys to the supplied list of keys.
+ * This operation is multi-thread safe.
+ *
+ * @param h
+ * Hash table to look in.
+ * @param keys
+ * A pointer to a list of where keys will be written.
+ * Must be large enough to fit a potentially full hash map.
+ * @return
+ * The number of found keys.
+ */
+unsigned int
+rte_hash_keys(const struct rte_hash *h, void *keys);
#ifdef __cplusplus
}
#endif