PLEASE IGNORE.
The patch description is rubbish.
Will post a v2.
> From: Morten Brørup [mailto:[email protected]]
> Sent: Tuesday, 20 January 2026 09.21
>
> Removed explicit test for build time constant request size,
> and added comment that the compiler loop unrolls when request size is
> build time constant, to improve source code readability.
>
> Also, when putting objects, the compiler does not know if calling
> rte_mempool_ops_enqueue_bulk() modifies cache->len, so load it before
> the
> call, so it doesn't have to be loaded again after the call.
>
> Signed-off-by: Morten Brørup <[email protected]>
> ---
> lib/mempool/rte_mempool.h | 38 ++++++++++----------------------------
> 1 file changed, 10 insertions(+), 28 deletions(-)
>
> diff --git a/lib/mempool/rte_mempool.h b/lib/mempool/rte_mempool.h
> index aedc100964..61b415e336 100644
> --- a/lib/mempool/rte_mempool.h
> +++ b/lib/mempool/rte_mempool.h
> @@ -1410,8 +1410,9 @@ rte_mempool_do_generic_put(struct rte_mempool
> *mp, void * const *obj_table,
> * Flush the cache to make room for the objects.
> */
> cache_objs = &cache->objs[0];
> - rte_mempool_ops_enqueue_bulk(mp, cache_objs, cache->len);
> + const uint32_t len = cache->len;
> cache->len = n;
> + rte_mempool_ops_enqueue_bulk(mp, cache_objs, len);
> } else {
> /* The request itself is too big for the cache. */
> goto driver_enqueue_stats_incremented;
> @@ -1531,11 +1532,11 @@ rte_mempool_do_generic_get(struct rte_mempool
> *mp, void **obj_table,
> cache_objs = &cache->objs[cache->len];
>
> __rte_assume(cache->len <= RTE_MEMPOOL_CACHE_MAX_SIZE * 2);
> - if (__rte_constant(n) && n <= cache->len) {
> + if (likely(n <= cache->len)) {
> /*
> - * The request size is known at build time, and
> - * the entire request can be satisfied from the cache,
> - * so let the compiler unroll the fixed length copy loop.
> + * The entire request can be satisfied from the cache.
> + * If the request size is known at build time,
> + * the compiler unrolls the fixed length copy loop.
> */
> cache->len -= n;
> for (index = 0; index < n; index++)
> @@ -1547,31 +1548,13 @@ rte_mempool_do_generic_get(struct rte_mempool
> *mp, void **obj_table,
> return 0;
> }
>
> - /*
> - * Use the cache as much as we have to return hot objects first.
> - * If the request size 'n' is known at build time, the above
> comparison
> - * ensures that n > cache->len here, so omit RTE_MIN().
> - */
> - len = __rte_constant(n) ? cache->len : RTE_MIN(n, cache->len);
> - cache->len -= len;
> + /* Use the cache as much as we have to return hot objects first.
> */
> + len = cache->len;
> remaining = n - len;
> + cache->len = 0;
> for (index = 0; index < len; index++)
> *obj_table++ = *--cache_objs;
>
> - /*
> - * If the request size 'n' is known at build time, the case
> - * where the entire request can be satisfied from the cache
> - * has already been handled above, so omit handling it here.
> - */
> - if (!__rte_constant(n) && likely(remaining == 0)) {
> - /* The entire request is satisfied from the cache. */
> -
> - RTE_MEMPOOL_CACHE_STAT_ADD(cache, get_success_bulk, 1);
> - RTE_MEMPOOL_CACHE_STAT_ADD(cache, get_success_objs, n);
> -
> - return 0;
> - }
> -
> /* Dequeue below would overflow mem allocated for cache? */
> if (unlikely(remaining > RTE_MEMPOOL_CACHE_MAX_SIZE))
> goto driver_dequeue;
> @@ -1592,11 +1575,10 @@ rte_mempool_do_generic_get(struct rte_mempool
> *mp, void **obj_table,
> __rte_assume(cache->size <= RTE_MEMPOOL_CACHE_MAX_SIZE);
> __rte_assume(remaining <= RTE_MEMPOOL_CACHE_MAX_SIZE);
> cache_objs = &cache->objs[cache->size + remaining];
> + cache->len = cache->size;
> for (index = 0; index < remaining; index++)
> *obj_table++ = *--cache_objs;
>
> - cache->len = cache->size;
> -
> RTE_MEMPOOL_CACHE_STAT_ADD(cache, get_success_bulk, 1);
> RTE_MEMPOOL_CACHE_STAT_ADD(cache, get_success_objs, n);
>
> --
> 2.43.0
