On Sun, Oct 01, 2017 at 02:59:01PM +0530, Santosh Shukla wrote:

Some mempool hw like octeontx/fpa block, demands block size
(/total_elem_sz) aligned object start address.

Introducing an MEMPOOL_F_CAPA_BLK_ALIGNED_OBJECTS flag.
If this flag is set:
- Align object start address(vaddr) to a multiple of total_elt_sz.
- Allocate one additional object. Additional object is needed to make
  sure that requested 'n' object gets correctly populated.

Example:
- Let's say that we get 'x' size of memory chunk from memzone.
- And application has requested 'n' object from mempool.
- Ideally, we start using objects at start address 0 to...(x-block_sz)
  for n obj.
- Not necessarily first object address i.e. 0 is aligned to block_sz.
- So we derive 'offset' value for block_sz alignment purpose i.e..'off'.
- That 'off' makes sure that start address of object is blk_sz aligned.
- Calculating 'off' may end up sacrificing first block_sz area of
  memzone area x. So total number of the object which can fit in the
  pool area is n-1, Which is incorrect behavior.

Therefore we request one additional object (/block_sz area) from memzone
when MEMPOOL_F_CAPA_BLK_ALIGNED_OBJECTS flag is set.

Signed-off-by: Santosh Shukla <redacted>
Signed-off-by: Jerin Jacob <redacted>
Tested-by: Hemant Agrawal <redacted>

Acked-by: Olivier Matz <redacted>