Man page 9 : mempool_create

mempool_create - create a memory pool

mempool_t * mempool_create(int  min_nr , mempool_alloc_t *  alloc_fn , mempool_free_t *  free_fn , void *  pool_data );

min_nr
    the minimum number of elements guaranteed to be allocated for this pool.

alloc_fn
    user-defined element-allocation function.

free_fn
    user-defined element-freeing function.

pool_data
    optional private data available to the user-defined functions.

this function creates and allocates a guaranteed size, preallocated memory pool. The pool can be used from the mempool_alloc and mempool_free functions. This function might sleep. Both the alloc_fn and the free_fn functions might sleep - as long as the mempool_alloc function is not called from IRQ contexts.