Allocate an element from a specific memory pool
void * mempool_alloc(mempool_t * pool, gfp_t gfp_mask);
pool
pointer to the memory pool which was allocated via mempool_create.
gfp_mask
the usual allocation bitmask.
this function only sleeps if the alloc_fn function sleeps or returns NULL. Note that due to preallocation, this function *never* fails when called from process contexts. (it might fail if called from an IRQ context.)
using __GFP_ZERO is not supported.