| Message ID | 1452704348-11818-1-git-send-email-ivan.khoronzhuk@linaro.org |
|---|---|
| State | New |
| Headers | show |
Maximum headroom is defined in ODP_PACKET_MAX_HEADROOM and is an implementation specific value and will not be greater than uint32/2. Having said that the current definition of headroom in ODP is that it will not exceed a single segment meaning the headroom will NOT overflow by adding an empty segment before. Regarding returning the previous allocated headroom, IMO it is a stale value and is of no significance to the existing application. If you have any use-case in mind for returning previous headroom pls share. Regards, Bala On 13 January 2016 at 22:29, Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> wrote: > It can be used to restore headroom later. Does it possible a headroom > to be > sizeof(int32)/2? > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> > --- > include/odp/api/packet_io.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/include/odp/api/packet_io.h b/include/odp/api/packet_io.h > index cf92751..7b9d82a 100644 > --- a/include/odp/api/packet_io.h > +++ b/include/odp/api/packet_io.h > @@ -356,12 +356,12 @@ int odp_pktio_skip_set(odp_pktio_t pktio, uint32_t offset); > * Must not exceed the implementation > * defined ODP_PACKET_MAX_HEADROOM. > * > - * @retval 0 on success > + * @retval prevoius headroom > * @retval <0 on failure > * > * @note Optional. > */ > -int odp_pktio_headroom_set(odp_pktio_t pktio, uint32_t headroom); > +int32_t odp_pktio_headroom_set(odp_pktio_t pktio, int32_t headroom); > > /** > * Get printable value for an odp_pktio_t > -- > 1.9.1 > > _______________________________________________ > lng-odp mailing list > lng-odp@lists.linaro.org > https://lists.linaro.org/mailman/listinfo/lng-odp
Once we add the ability to attach additional segments to a packet (as is being discussed in other threads) we may wish to revisit the concept of "extensible" headroom/tailroom. As long as packets can be extended there's no logical reason why headroom/tailroom need be limited to a single segment. On Thu, Jan 14, 2016 at 6:03 AM, Bala Manoharan <bala.manoharan@linaro.org> wrote: > Maximum headroom is defined in ODP_PACKET_MAX_HEADROOM and is an > implementation specific value and will not be greater than uint32/2. > > Having said that the current definition of headroom in ODP is that it > will not exceed a single segment meaning the headroom will NOT > overflow by adding an empty segment before. > > Regarding returning the previous allocated headroom, IMO it is a stale > value and is of no significance to the existing application. If you > have any use-case in mind for returning previous headroom pls share. > > Regards, > Bala > > > On 13 January 2016 at 22:29, Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> > wrote: > > It can be used to restore headroom later. Does it possible a headroom > > to be > sizeof(int32)/2? > > > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> > > --- > > include/odp/api/packet_io.h | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/include/odp/api/packet_io.h b/include/odp/api/packet_io.h > > index cf92751..7b9d82a 100644 > > --- a/include/odp/api/packet_io.h > > +++ b/include/odp/api/packet_io.h > > @@ -356,12 +356,12 @@ int odp_pktio_skip_set(odp_pktio_t pktio, uint32_t > offset); > > * Must not exceed the implementation > > * defined ODP_PACKET_MAX_HEADROOM. > > * > > - * @retval 0 on success > > + * @retval prevoius headroom > > * @retval <0 on failure > > * > > * @note Optional. > > */ > > -int odp_pktio_headroom_set(odp_pktio_t pktio, uint32_t headroom); > > +int32_t odp_pktio_headroom_set(odp_pktio_t pktio, int32_t headroom); > > > > /** > > * Get printable value for an odp_pktio_t > > -- > > 1.9.1 > > > > _______________________________________________ > > lng-odp mailing list > > lng-odp@lists.linaro.org > > https://lists.linaro.org/mailman/listinfo/lng-odp > _______________________________________________ > lng-odp mailing list > lng-odp@lists.linaro.org > https://lists.linaro.org/mailman/listinfo/lng-odp >
On 14.01.16 14:03, Bala Manoharan wrote: > Maximum headroom is defined in ODP_PACKET_MAX_HEADROOM and is an > implementation specific value and will not be greater than uint32/2. > > Having said that the current definition of headroom in ODP is that it > will not exceed a single segment meaning the headroom will NOT > overflow by adding an empty segment before. > > Regarding returning the previous allocated headroom, IMO it is a stale > value and is of no significance to the existing application. If you > have any use-case in mind for returning previous headroom pls share. > > Regards, > Bala > at least one usecase it's testing, when the same pktio can be used farther after testing/changing headroom call. Yes, it can be tested with own pktio, but it's simpler. For instance, like it's done in classification_test_pktio_set_headroom)_ test case. By a big account, headroom has to be restored. > > On 13 January 2016 at 22:29, Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> wrote: >> It can be used to restore headroom later. Does it possible a headroom >> to be > sizeof(int32)/2? >> >> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> >> --- >> include/odp/api/packet_io.h | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/include/odp/api/packet_io.h b/include/odp/api/packet_io.h >> index cf92751..7b9d82a 100644 >> --- a/include/odp/api/packet_io.h >> +++ b/include/odp/api/packet_io.h >> @@ -356,12 +356,12 @@ int odp_pktio_skip_set(odp_pktio_t pktio, uint32_t offset); >> * Must not exceed the implementation >> * defined ODP_PACKET_MAX_HEADROOM. >> * >> - * @retval 0 on success >> + * @retval prevoius headroom >> * @retval <0 on failure >> * >> * @note Optional. >> */ >> -int odp_pktio_headroom_set(odp_pktio_t pktio, uint32_t headroom); >> +int32_t odp_pktio_headroom_set(odp_pktio_t pktio, int32_t headroom); >> >> /** >> * Get printable value for an odp_pktio_t >> -- >> 1.9.1 >> >> _______________________________________________ >> lng-odp mailing list >> lng-odp@lists.linaro.org >> https://lists.linaro.org/mailman/listinfo/lng-odp
diff --git a/include/odp/api/packet_io.h b/include/odp/api/packet_io.h index cf92751..7b9d82a 100644 --- a/include/odp/api/packet_io.h +++ b/include/odp/api/packet_io.h @@ -356,12 +356,12 @@ int odp_pktio_skip_set(odp_pktio_t pktio, uint32_t offset); * Must not exceed the implementation * defined ODP_PACKET_MAX_HEADROOM. * - * @retval 0 on success + * @retval prevoius headroom * @retval <0 on failure * * @note Optional. */ -int odp_pktio_headroom_set(odp_pktio_t pktio, uint32_t headroom); +int32_t odp_pktio_headroom_set(odp_pktio_t pktio, int32_t headroom); /** * Get printable value for an odp_pktio_t
It can be used to restore headroom later. Does it possible a headroom to be > sizeof(int32)/2? Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> --- include/odp/api/packet_io.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)