Re: [dpdk-dev] [PATCH v4 5/7] mempool: detect physical contiguous object in pool

[Olivier MATZ <olivier.matz@6wind.com>]

On Mon, Sep 04, 2017 at 08:17:11PM +0530, santosh wrote:
> 
> On Monday 04 September 2017 08:13 PM, Olivier MATZ wrote:
> > On Tue, Aug 15, 2017 at 11:37:41AM +0530, Santosh Shukla wrote:
> >> The memory area containing all the objects must be physically
> >> contiguous.
> >> Introducing MEMPOOL_F_CAPA_PHYS_CONTIG flag for such use-case.
> >>
> >> The flag useful to detect whether pool area has sufficient space
> >> to fit all objects. If not then return -ENOSPC.
> >> This way, we make sure that all object within a pool is contiguous.
> >>
> >> Signed-off-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
> >> Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
> >> ---
> >>  lib/librte_mempool/rte_mempool.c | 8 ++++++++
> >>  lib/librte_mempool/rte_mempool.h | 1 +
> >>  2 files changed, 9 insertions(+)
> >>
> >> diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
> >> index d518c53de..19e5e6ddf 100644
> >> --- a/lib/librte_mempool/rte_mempool.c
> >> +++ b/lib/librte_mempool/rte_mempool.c
> >> @@ -370,6 +370,14 @@ rte_mempool_populate_phys(struct rte_mempool *mp, char *vaddr,
> >>  
> >>  	total_elt_sz = mp->header_size + mp->elt_size + mp->trailer_size;
> >>  
> >> +	/* Detect pool area has sufficient space for elements */
> >> +	if (mp->flags & MEMPOOL_F_CAPA_PHYS_CONTIG) {
> >> +		if (len < total_elt_sz * mp->size) {
> >> +			RTE_LOG(ERR, MEMPOOL, "pool area %" PRIx64 " not enough\n", (uint64_t)len);
> >> +			return -ENOSPC;
> >> +		}
> >> +	}
> >> +
> >>  	memhdr = rte_zmalloc("MEMPOOL_MEMHDR", sizeof(*memhdr), 0);
> >>  	if (memhdr == NULL)
> >>  		return -ENOMEM;
> >> diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
> >> index bc4a1dac7..a4bfdb56e 100644
> >> --- a/lib/librte_mempool/rte_mempool.h
> >> +++ b/lib/librte_mempool/rte_mempool.h
> >> @@ -265,6 +265,7 @@ struct rte_mempool {
> >>  #define MEMPOOL_F_SC_GET         0x0008 /**< Default get is "single-consumer".*/
> >>  #define MEMPOOL_F_POOL_CREATED   0x0010 /**< Internal: pool is created. */
> >>  #define MEMPOOL_F_NO_PHYS_CONTIG 0x0020 /**< Don't need physically contiguous objs. */
> >> +#define MEMPOOL_F_CAPA_PHYS_CONTIG 0x0040 /**< Detect physcially contiguous objs */
> >>  
> > The description should be longer. It is impossible to understand what is the
> > meaning of this capability flag by just reading the comment.
> >
> > Example:
> > /**
> >  * This capability flag is advertised by a mempool handler if the whole
> >  * memory area containing the objects must be physically contiguous.
> >  */
> 
> in v5, Thanks.
> 
> 

Can you please also add that this flag should not be passed by the application?