[dpdk-dev] [PATCH] compressdev: clarify destination buffer size for corner case

[dpdk-dev] [PATCH] compressdev: clarify destination buffer size for corner case

[Fiona Trahe]

Clarify the corner case with incompressible data
whereby the output can actually be greater than the
uncompressed data.

Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
---
 lib/librte_compressdev/rte_comp.h |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/lib/librte_compressdev/rte_comp.h b/lib/librte_compressdev/rte_comp.h
index b7474c4..95306c5 100644
--- a/lib/librte_compressdev/rte_comp.h
+++ b/lib/librte_compressdev/rte_comp.h
@@ -323,6 +323,12 @@ struct rte_comp_op {
 	 * If the output data is expected to be bigger than this a chain of
 	 * mbufs can be passed to the PMD if the PMD's capabilities indicate
 	 * it supports this.
+	 *
+	 * @note, if incompressible data is passed to an engine for compression
+	 * using RTE_COMP_ALGO_DEFLATE, it's possible for the output data
+	 * to be larger than the uncompressed data, due to the inclusion
+	 * of the DEFLATE header blocks. The size of m_dst should accommodate
+	 * this, else OUT_OF_SPACE errors can be expected in this case.
 	 */
 
 	struct {
-- 
1.7.0.7

Re: [dpdk-dev] [PATCH] compressdev: clarify destination buffer size for corner case

[Dybkowski, AdamX]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Fiona Trahe
> Sent: Thursday, 25 July, 2019 19:04
> To: dev@dpdk.org
> Cc: akhil.goyal@nxp.com; Trahe, Fiona <fiona.trahe@intel.com>;
> shallyv@marvell.com
> Subject: [dpdk-dev] [PATCH] compressdev: clarify destination buffer size for
> corner case
> 
> Clarify the corner case with incompressible data whereby the output can
> actually be greater than the uncompressed data.
> 
> Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
> ---

Acked-by: Adam Dybkowski <adamx.dybkowski@intel.com>

Re: [dpdk-dev] [PATCH] compressdev: clarify destination buffer size for corner case

[Akhil Goyal]

Hi Shally,

> >
> > Clarify the corner case with incompressible data whereby the output can
> > actually be greater than the uncompressed data.
> >
> > Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
> > ---
> 
> Acked-by: Adam Dybkowski <adamx.dybkowski@intel.com>

Are you Ok with this change at this point in lib? Normally no change is accepted in lib beyond RC2, but since this is only changing the comments. We can take it if it fine with multiple contributors and not just Intel.

Re: [dpdk-dev] [EXT] [PATCH] compressdev: clarify destination buffer size for corner case

[Shally Verma]

> -----Original Message-----
> From: Fiona Trahe <fiona.trahe@intel.com>
> Sent: Thursday, July 25, 2019 10:34 PM
> To: dev@dpdk.org
> Cc: akhil.goyal@nxp.com; fiona.trahe@intel.com; Shally Verma
> <shallyv@marvell.com>
> Subject: [EXT] [PATCH] compressdev: clarify destination buffer size for
> corner case
> 
> External Email
> 
> ----------------------------------------------------------------------
> Clarify the corner case with incompressible data whereby the output can
> actually be greater than the uncompressed data.
> 
> Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
> ---
>  lib/librte_compressdev/rte_comp.h |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/lib/librte_compressdev/rte_comp.h
> b/lib/librte_compressdev/rte_comp.h
> index b7474c4..95306c5 100644
> --- a/lib/librte_compressdev/rte_comp.h
> +++ b/lib/librte_compressdev/rte_comp.h
> @@ -323,6 +323,12 @@ struct rte_comp_op {
>  	 * If the output data is expected to be bigger than this a chain of
>  	 * mbufs can be passed to the PMD if the PMD's capabilities indicate
>  	 * it supports this.
> +	 *
> +	 * @note, if incompressible data is passed to an engine for
> compression
> +	 * using RTE_COMP_ALGO_DEFLATE, it's possible for the output data
> +	 * to be larger than the uncompressed data, due to the inclusion
> +	 * of the DEFLATE header blocks. The size of m_dst should
> accommodate
> +	 * this, else OUT_OF_SPACE errors can be expected in this case.
>  	 */
> 
>  	struct {
> --
> 1.7.0.7
Acked-by: Shally Verma <shallyv@marvell.com>

Re: [dpdk-dev] [EXT] [PATCH] compressdev: clarify destination buffer size for corner case

[Akhil Goyal]

> >
> > ----------------------------------------------------------------------
> > Clarify the corner case with incompressible data whereby the output can
> > actually be greater than the uncompressed data.
> >
> > Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
> > ---
> >  lib/librte_compressdev/rte_comp.h |    6 ++++++
> >  1 files changed, 6 insertions(+), 0 deletions(-)
> >
> > diff --git a/lib/librte_compressdev/rte_comp.h
> > b/lib/librte_compressdev/rte_comp.h
> > index b7474c4..95306c5 100644
> > --- a/lib/librte_compressdev/rte_comp.h
> > +++ b/lib/librte_compressdev/rte_comp.h
> > @@ -323,6 +323,12 @@ struct rte_comp_op {
> >  	 * If the output data is expected to be bigger than this a chain of
> >  	 * mbufs can be passed to the PMD if the PMD's capabilities indicate
> >  	 * it supports this.
> > +	 *
> > +	 * @note, if incompressible data is passed to an engine for
> > compression
> > +	 * using RTE_COMP_ALGO_DEFLATE, it's possible for the output data
> > +	 * to be larger than the uncompressed data, due to the inclusion
> > +	 * of the DEFLATE header blocks. The size of m_dst should
> > accommodate
> > +	 * this, else OUT_OF_SPACE errors can be expected in this case.
> >  	 */
> >
> >  	struct {
> > --
> > 1.7.0.7
> Acked-by: Shally Verma <shallyv@marvell.com>

Applied to dpdk-next-crypto

Thanks.