On Fri, Dec 22, 2017 at 09:48:01PM +0530, Hemant Agrawal wrote: > On 12/22/2017 7:29 PM, Olivier MATZ wrote: > > On Wed, Dec 20, 2017 at 05:29:59PM +0530, Hemant Agrawal wrote: > > > On 12/19/2017 6:38 PM, Hemant Agrawal wrote: > > > > > > > > > That's true, I commented too fast :) > > > > > And what about using mp->nb_mem_chunks instead? Would it do the job > > > > > in your use-case? > > > > > > > > It should work. Let me check it out. > > > > > > There is a slight problem with nb_mem_chunks. > > > > > > It is getting incremented in the end of "rte_mempool_populate_phys", > > > while the elements are getting populated before it in the call of > > > mempool_add_elem. > > > > > > I can use nb_mem_chunks are '0' check. However it can break in future if > > > mempool_populate_phys changes. > > > > Sorry, I'm not sure I'm getting what you say. > > > > My question was about using mp->nb_mem_chunks instead of a new flag in the > > dppa driver. Am I missing something? > > > > mp->nb_mem_chunks gets finalized when the mempool is fully created. It's > value is transient before that i.e. it will keep on changing on the every > call to rte_mempool_populate_phys. > > However, we need this information on the very first element allocation. So, > nb_mem_chunks will not work.
I see 2 other alternatives: 1/ in your driver, register a callback rte_mempool_ops_register_memory_area() that sets a private flag if (len < total_elt_sz * mp->size). 2/ Move STAILQ_INSERT_TAIL(&mp->mem_list, memhdr, next); mp->nb_mem_chunks++; before the calls to mempool_add_elem(), and in your driver check if SLIST_FIRST(&mp->mem_list)->len < total_elt_sz * mp->size If we can avoid to again create another flag, it is better.