Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
19/02/2018 15:13, Matan Azrad: > Hi Wiles > > From: Wiles, Keith, Monday, February 19, 2018 3:56 PM > > > On Feb 19, 2018, at 12:03 AM, Matan Azrad wrote: > > >> Is this the type of API that needs to be marked experimental, > > > > > > I think it is relevant to any exposed API(not only for internal > > > libraries). > > > > > >> we should be able to prove these functions, correct? > > > > > > Don't we need to prove any function in DPDK? > > > What is your point? > > > > > > My point is this is a inline function and can not be placed in the .map > > file as a > > external API. > > Doesn't each API in .h file external? Why not? > If it shouldn't be external and should be in .h file, I think it should be > marked as internal, no? > > > These simple type of APIs are easy to prove and making them > > experimental seems to just cause an extra step. > > As Thomas mentioned here: > https://dpdk.org/ml/archives/dev/2018-January/087719.html > > Any new API should be experimental. > > Thomas, Is it different for .h file inline APIs? No, it is not different for inline functions. If we are discussing the policy for every function, it is not a policy anymore :) It was agreed to notify the users of the new functions, so it gives time to confirm the function before making it "stable". Even if the function looks obvious, I think we should follow the policy. So, yes, please add the experimental tag.
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
> On Feb 19, 2018, at 8:13 AM, Matan Azrad wrote: > > Hi Wiles > > From: Wiles, Keith, Monday, February 19, 2018 3:56 PM >>> On Feb 19, 2018, at 12:03 AM, Matan Azrad wrote: Is this the type of API that needs to be marked experimental, >>> >>> I think it is relevant to any exposed API(not only for internal libraries). >>> we should be able to prove these functions, correct? >>> >>> Don't we need to prove any function in DPDK? >>> What is your point? >> >> >> My point is this is a inline function and can not be placed in the .map file >> as a >> external API. > > Doesn't each API in .h file external? Why not? > If it shouldn't be external and should be in .h file, I think it should be > marked as internal, no? We do not do a great job of using private headers as most of our headers are public ones and in the case or private they would not be external. > >> These simple type of APIs are easy to prove and making them >> experimental seems to just cause an extra step. > > As Thomas mentioned here: > https://dpdk.org/ml/archives/dev/2018-January/087719.html > > Any new API should be experimental. > > Thomas, Is it different for .h file inline APIs? > >> If the functions are not required that is a different problem or if the API >> is really only ever used by a >> single function or module of files then it should be moved to the module/file >> and made locate to the module/file. > > Agree. > Looks like this function makes sense and may be used by other modules later. > Regards, Keith
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
Hi Wiles From: Wiles, Keith, Monday, February 19, 2018 3:56 PM > > On Feb 19, 2018, at 12:03 AM, Matan Azrad wrote: > >> Is this the type of API that needs to be marked experimental, > > > > I think it is relevant to any exposed API(not only for internal libraries). > > > >> we should be able to prove these functions, correct? > > > > Don't we need to prove any function in DPDK? > > What is your point? > > > My point is this is a inline function and can not be placed in the .map file > as a > external API. Doesn't each API in .h file external? Why not? If it shouldn't be external and should be in .h file, I think it should be marked as internal, no? > These simple type of APIs are easy to prove and making them > experimental seems to just cause an extra step. As Thomas mentioned here: https://dpdk.org/ml/archives/dev/2018-January/087719.html Any new API should be experimental. Thomas, Is it different for .h file inline APIs? > If the functions are not required that is a different problem or if the API > is really only ever used by a > single function or module of files then it should be moved to the module/file > and made locate to the module/file. Agree. Looks like this function makes sense and may be used by other modules later.
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
> On Feb 19, 2018, at 12:03 AM, Matan Azrad wrote: > > >> >> Is this the type of API that needs to be marked experimental, > > I think it is relevant to any exposed API(not only for internal libraries). > >> we should be able to prove these functions, correct? > > Don't we need to prove any function in DPDK? > What is your point? My point is this is a inline function and can not be placed in the .map file as a external API. These simple type of APIs are easy to prove and making them experimental seems to just cause an extra step. If the functions are not required that is a different problem or if the API is really only ever used by a single function or module of files then it should be moved to the module/file and made locate to the module/file. > >>> Matan >> >> Regards, >> Keith Regards, Keith
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
Hi Matan,
On Sun, Feb 18, 2018 at 06:11:20AM +, Matan Azrad wrote:
> Hi Pavan
>
> Please see some comments below.
>
> From: Pavan Nikhilesh, Saturday, February 17, 2018 12:50 PM
> > Add 32b and 64b API's to align the given integer to the previous power of 2.
> >
> > Signed-off-by: Pavan Nikhilesh
> > ---
> > lib/librte_eal/common/include/rte_common.h | 36
> > ++
> > 1 file changed, 36 insertions(+)
> >
> > diff --git a/lib/librte_eal/common/include/rte_common.h
> > b/lib/librte_eal/common/include/rte_common.h
> > index c7803e41c..126914f07 100644
> > --- a/lib/librte_eal/common/include/rte_common.h
> > +++ b/lib/librte_eal/common/include/rte_common.h
> > @@ -259,6 +259,24 @@ rte_align32pow2(uint32_t x)
> > return x + 1;
> > }
> >
> > +/**
> > + * Aligns input parameter to the previous power of 2
> > + *
> > + * @param x
> > + * The integer value to algin
> > + *
> > + * @return
> > + * Input parameter aligned to the previous power of 2
>
> I think the zero case(x=0) result should be documented.
The existing API i.e. rte_align32pow2() behaves in similar manner i.e. returns
0 when 0 is passed.
>
> > + */
> > +static inline uint32_t
> > +rte_align32lowpow2(uint32_t x)
>
> What do you think about " rte_align32prevpow2"?
I think rte_align32prevpow2() fits better will modify and send v2.
>
> > +{
> > + x = rte_align32pow2(x);
>
> In case of x is power of 2 number(already aligned), looks like the
> result here is x and the final result is (x >> 1)?
> Is it as you expect?
I overlooked that bit while trying to make use of the existing API, will modify
the implementation to return x if its already a power of 2.
>
> > + x--;
> > +
> > + return x - (x >> 1);
>
> Why can't the implementation just be:
> return rte_align32pow2(x) >> 1;
>
> If the above is correct, Are you sure we need this API?
>
> > +}
> > +
> > /**
> > * Aligns 64b input parameter to the next power of 2
> > *
> > @@ -282,6 +300,24 @@ rte_align64pow2(uint64_t v)
> > return v + 1;
> > }
> >
> > +/**
> > + * Aligns 64b input parameter to the previous power of 2
> > + *
> > + * @param v
> > + * The 64b value to align
> > + *
> > + * @return
> > + * Input parameter aligned to the previous power of 2
> > + */
> > +static inline uint64_t
> > +rte_align64lowpow2(uint64_t v)
> > +{
> > + v = rte_align64pow2(v);
> > + v--;
> > +
> > + return v - (v >> 1);
> > +}
> > +
>
> Same comments for 64b API.
>
> > /*** Macros for calculating min and max **/
> >
> > /**
> > --
> > 2.16.1
>
>
> If it is a new API, I think it should be added to the map file and to be
> tagged as experimental. No?
Static inline functions need not be a part of map files, as for experimental
tag I don't think its needed for a math API. I don't have a strong opinion
tagging it experimental, if it is really needed I will send a re-do the patch
marking it experimental.
>
> Matan
Thanks,
Pavan
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
> From: Wiles, Keith, Sunday, February 18, 2018 5:39 PM
> > On Feb 18, 2018, at 12:11 AM, Matan Azrad
> wrote:
> >
> > Hi Pavan
> >
> > Please see some comments below.
> >
> > From: Pavan Nikhilesh, Saturday, February 17, 2018 12:50 PM
> >> Add 32b and 64b API's to align the given integer to the previous power of
> 2.
> >>
> >> Signed-off-by: Pavan Nikhilesh
> >> ---
> >> lib/librte_eal/common/include/rte_common.h | 36
> >> ++
> >> 1 file changed, 36 insertions(+)
> >>
> >> diff --git a/lib/librte_eal/common/include/rte_common.h
> >> b/lib/librte_eal/common/include/rte_common.h
> >> index c7803e41c..126914f07 100644
> >> --- a/lib/librte_eal/common/include/rte_common.h
> >> +++ b/lib/librte_eal/common/include/rte_common.h
> >> @@ -259,6 +259,24 @@ rte_align32pow2(uint32_t x)
> >>return x + 1;
> >> }
> >>
> >> +/**
> >> + * Aligns input parameter to the previous power of 2
> >> + *
> >> + * @param x
> >> + * The integer value to algin
> >> + *
> >> + * @return
> >> + * Input parameter aligned to the previous power of 2
> >
> > I think the zero case(x=0) result should be documented.
> >
> >> + */
> >> +static inline uint32_t
> >> +rte_align32lowpow2(uint32_t x)
> >
> > What do you think about " rte_align32prevpow2"?
> >
> >> +{
> >> + x = rte_align32pow2(x);
> >
> > In case of x is power of 2 number(already aligned), looks like the
> result here is x and the final result is (x >> 1)?
> > Is it as you expect?
> >
> >> + x--;
> >> +
> >> + return x - (x >> 1);
> >
> > Why can't the implementation just be:
> > return rte_align32pow2(x) >> 1;
> >
> > If the above is correct, Are you sure we need this API?
> >
> >> +}
> >> +
> >> /**
> >> * Aligns 64b input parameter to the next power of 2
> >> *
> >> @@ -282,6 +300,24 @@ rte_align64pow2(uint64_t v)
> >>return v + 1;
> >> }
> >>
> >> +/**
> >> + * Aligns 64b input parameter to the previous power of 2
> >> + *
> >> + * @param v
> >> + * The 64b value to align
> >> + *
> >> + * @return
> >> + * Input parameter aligned to the previous power of 2
> >> + */
> >> +static inline uint64_t
> >> +rte_align64lowpow2(uint64_t v)
> >> +{
> >> + v = rte_align64pow2(v);
> >> + v--;
> >> +
> >> + return v - (v >> 1);
> >> +}
> >> +
> >
> > Same comments for 64b API.
> >
> >> /*** Macros for calculating min and max **/
> >>
> >> /**
> >> --
> >> 2.16.1
> >
> >
> > If it is a new API, I think it should be added to the map file and to be
> > tagged
> as experimental. No?
> >
>
> Is this the type of API that needs to be marked experimental,
I think it is relevant to any exposed API(not only for internal libraries).
> we should be able to prove these functions, correct?
Don't we need to prove any function in DPDK?
What is your point?
> > Matan
>
> Regards,
> Keith
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
> On Feb 18, 2018, at 12:11 AM, Matan Azrad wrote:
>
> Hi Pavan
>
> Please see some comments below.
>
> From: Pavan Nikhilesh, Saturday, February 17, 2018 12:50 PM
>> Add 32b and 64b API's to align the given integer to the previous power of 2.
>>
>> Signed-off-by: Pavan Nikhilesh
>> ---
>> lib/librte_eal/common/include/rte_common.h | 36
>> ++
>> 1 file changed, 36 insertions(+)
>>
>> diff --git a/lib/librte_eal/common/include/rte_common.h
>> b/lib/librte_eal/common/include/rte_common.h
>> index c7803e41c..126914f07 100644
>> --- a/lib/librte_eal/common/include/rte_common.h
>> +++ b/lib/librte_eal/common/include/rte_common.h
>> @@ -259,6 +259,24 @@ rte_align32pow2(uint32_t x)
>> return x + 1;
>> }
>>
>> +/**
>> + * Aligns input parameter to the previous power of 2
>> + *
>> + * @param x
>> + * The integer value to algin
>> + *
>> + * @return
>> + * Input parameter aligned to the previous power of 2
>
> I think the zero case(x=0) result should be documented.
>
>> + */
>> +static inline uint32_t
>> +rte_align32lowpow2(uint32_t x)
>
> What do you think about " rte_align32prevpow2"?
>
>> +{
>> +x = rte_align32pow2(x);
>
> In case of x is power of 2 number(already aligned), looks like the
> result here is x and the final result is (x >> 1)?
> Is it as you expect?
>
>> +x--;
>> +
>> +return x - (x >> 1);
>
> Why can't the implementation just be:
> return rte_align32pow2(x) >> 1;
>
> If the above is correct, Are you sure we need this API?
>
>> +}
>> +
>> /**
>> * Aligns 64b input parameter to the next power of 2
>> *
>> @@ -282,6 +300,24 @@ rte_align64pow2(uint64_t v)
>> return v + 1;
>> }
>>
>> +/**
>> + * Aligns 64b input parameter to the previous power of 2
>> + *
>> + * @param v
>> + * The 64b value to align
>> + *
>> + * @return
>> + * Input parameter aligned to the previous power of 2
>> + */
>> +static inline uint64_t
>> +rte_align64lowpow2(uint64_t v)
>> +{
>> +v = rte_align64pow2(v);
>> +v--;
>> +
>> +return v - (v >> 1);
>> +}
>> +
>
> Same comments for 64b API.
>
>> /*** Macros for calculating min and max **/
>>
>> /**
>> --
>> 2.16.1
>
>
> If it is a new API, I think it should be added to the map file and to be
> tagged as experimental. No?
>
Is this the type of API that needs to be marked experimental, we should be able
to prove these functions, correct?
> Matan
Regards,
Keith
Re: [dpdk-dev] [PATCH 1/2] eal: add API to align integer to previous power of 2
Hi Pavan
Please see some comments below.
From: Pavan Nikhilesh, Saturday, February 17, 2018 12:50 PM
> Add 32b and 64b API's to align the given integer to the previous power of 2.
>
> Signed-off-by: Pavan Nikhilesh
> ---
> lib/librte_eal/common/include/rte_common.h | 36
> ++
> 1 file changed, 36 insertions(+)
>
> diff --git a/lib/librte_eal/common/include/rte_common.h
> b/lib/librte_eal/common/include/rte_common.h
> index c7803e41c..126914f07 100644
> --- a/lib/librte_eal/common/include/rte_common.h
> +++ b/lib/librte_eal/common/include/rte_common.h
> @@ -259,6 +259,24 @@ rte_align32pow2(uint32_t x)
> return x + 1;
> }
>
> +/**
> + * Aligns input parameter to the previous power of 2
> + *
> + * @param x
> + * The integer value to algin
> + *
> + * @return
> + * Input parameter aligned to the previous power of 2
I think the zero case(x=0) result should be documented.
> + */
> +static inline uint32_t
> +rte_align32lowpow2(uint32_t x)
What do you think about " rte_align32prevpow2"?
> +{
> + x = rte_align32pow2(x);
In case of x is power of 2 number(already aligned), looks like the
result here is x and the final result is (x >> 1)?
Is it as you expect?
> + x--;
> +
> + return x - (x >> 1);
Why can't the implementation just be:
return rte_align32pow2(x) >> 1;
If the above is correct, Are you sure we need this API?
> +}
> +
> /**
> * Aligns 64b input parameter to the next power of 2
> *
> @@ -282,6 +300,24 @@ rte_align64pow2(uint64_t v)
> return v + 1;
> }
>
> +/**
> + * Aligns 64b input parameter to the previous power of 2
> + *
> + * @param v
> + * The 64b value to align
> + *
> + * @return
> + * Input parameter aligned to the previous power of 2
> + */
> +static inline uint64_t
> +rte_align64lowpow2(uint64_t v)
> +{
> + v = rte_align64pow2(v);
> + v--;
> +
> + return v - (v >> 1);
> +}
> +
Same comments for 64b API.
> /*** Macros for calculating min and max **/
>
> /**
> --
> 2.16.1
If it is a new API, I think it should be added to the map file and to be tagged
as experimental. No?
Matan
