[v2,5/6] hash: fix to have more accurate key slot size
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Commit Message
This commit calculates the needed key slot size more
accurately. The previous local cache fix requires
the free slot ring to be larger than actually needed.
The calculation of the value is inaccurate.
Fixes: 5915699153d7 ("hash: fix scaling by reducing contention")
Signed-off-by: Yipeng Wang <yipeng1.wang@intel.com>
---
lib/librte_hash/rte_cuckoo_hash.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
Comments
> -----Original Message-----
> From: Wang, Yipeng1
> Sent: Friday, June 29, 2018 1:25 PM
> To: De Lara Guarch, Pablo <pablo.de.lara.guarch@intel.com>
> Cc: dev@dpdk.org; Wang, Yipeng1 <yipeng1.wang@intel.com>; Richardson,
> Bruce <bruce.richardson@intel.com>; honnappa.nagarahalli@arm.com;
> vguvva@caviumnetworks.com; brijesh.s.singh@gmail.com
> Subject: [PATCH v2 5/6] hash: fix to have more accurate key slot size
>
> This commit calculates the needed key slot size more accurately. The previous
> local cache fix requires the free slot ring to be larger than actually needed.
> The calculation of the value is inaccurate.
>
> Fixes: 5915699153d7 ("hash: fix scaling by reducing contention")
Missing "Cc: stable@dpdk.org).
Also, could you add this as the first patch of the set.
That way, it would be easier to backport (the patch will need modification, otherwise it won't compile).
@@ -133,13 +133,13 @@ rte_hash_create(const struct rte_hash_parameters *params)
* except for the first cache
*/
num_key_slots = params->entries + (RTE_MAX_LCORE - 1) *
- LCORE_CACHE_SIZE + 1;
+ (LCORE_CACHE_SIZE - 1) + 1;
else
num_key_slots = params->entries + 1;
snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
/* Create ring (Dummy slot index is not enqueued) */
- r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots - 1),
+ r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots),
params->socket_id, 0);
if (r == NULL) {
RTE_LOG(ERR, HASH, "memory allocation failed\n");
@@ -293,7 +293,7 @@ rte_hash_create(const struct rte_hash_parameters *params)
}
/* Populate free slots ring. Entry zero is reserved for key misses. */
- for (i = 1; i < params->entries + 1; i++)
+ for (i = 1; i < num_key_slots; i++)
rte_ring_sp_enqueue(r, (void *)((uintptr_t) i));
te->data = (void *) h;
@@ -412,7 +412,7 @@ void
rte_hash_reset(struct rte_hash *h)
{
void *ptr;
- unsigned i;
+ uint32_t tot_ring_cnt, i;
if (h == NULL)
return;
@@ -426,7 +426,13 @@ rte_hash_reset(struct rte_hash *h)
rte_pause();
/* Repopulate the free slots ring. Entry zero is reserved for key misses */
- for (i = 1; i < h->entries + 1; i++)
+ if (h->multi_writer_support)
+ tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
+ (LCORE_CACHE_SIZE - 1);
+ else
+ tot_ring_cnt = h->entries;
+
+ for (i = 1; i < tot_ring_cnt + 1; i++)
rte_ring_sp_enqueue(h->free_slots, (void *)((uintptr_t) i));
if (h->multi_writer_support) {