* [PATCH] bitops: Introduce BITS_PER_TYPE
@ 2018-07-06 9:44 Chris Wilson
2018-07-06 10:03 ` Jani Nikula
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Chris Wilson @ 2018-07-06 9:44 UTC (permalink / raw)
To: linux-kernel
Cc: Chris Wilson, Jani Nikula, Andy Gospodarek, David S . Miller,
Thomas Gleixner, Andrew Morton, Ingo Molnar
net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Andy Gospodarek <gospo@broadcom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
---
include/linux/bitops.h | 3 ++-
include/linux/net_dim.h | 1 -
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 4cac4e1a72ff..091cb17d1a9b 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -11,7 +11,8 @@
#define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
#define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
#define BITS_PER_BYTE 8
-#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
+#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
+#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
#endif
/*
diff --git a/include/linux/net_dim.h b/include/linux/net_dim.h
index 29ed8fd6379a..14f1734e740a 100644
--- a/include/linux/net_dim.h
+++ b/include/linux/net_dim.h
@@ -326,7 +326,6 @@ static inline void net_dim_sample(u16 event_ctr,
}
#define NET_DIM_NEVENTS 64
-#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
#define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))
static inline void net_dim_calc_stats(struct net_dim_sample *start,
--
2.18.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 9:44 [PATCH] bitops: Introduce BITS_PER_TYPE Chris Wilson
@ 2018-07-06 10:03 ` Jani Nikula
2018-07-06 17:48 ` Randy Dunlap
2018-07-06 21:57 ` Andrew Morton
2 siblings, 0 replies; 8+ messages in thread
From: Jani Nikula @ 2018-07-06 10:03 UTC (permalink / raw)
To: Chris Wilson, linux-kernel
Cc: Chris Wilson, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
On Fri, 06 Jul 2018, Chris Wilson <chris@chris-wilson.co.uk> wrote:
> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Andy Gospodarek <gospo@broadcom.com>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
> ---
> include/linux/bitops.h | 3 ++-
> include/linux/net_dim.h | 1 -
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 4cac4e1a72ff..091cb17d1a9b 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -11,7 +11,8 @@
> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
> #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
> #define BITS_PER_BYTE 8
> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
> +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
> #endif
>
> /*
> diff --git a/include/linux/net_dim.h b/include/linux/net_dim.h
> index 29ed8fd6379a..14f1734e740a 100644
> --- a/include/linux/net_dim.h
> +++ b/include/linux/net_dim.h
> @@ -326,7 +326,6 @@ static inline void net_dim_sample(u16 event_ctr,
> }
>
> #define NET_DIM_NEVENTS 64
> -#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> #define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))
>
> static inline void net_dim_calc_stats(struct net_dim_sample *start,
--
Jani Nikula, Intel Open Source Graphics Center
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 9:44 [PATCH] bitops: Introduce BITS_PER_TYPE Chris Wilson
2018-07-06 10:03 ` Jani Nikula
@ 2018-07-06 17:48 ` Randy Dunlap
2018-07-06 17:51 ` Chris Wilson
2018-07-06 21:57 ` Andrew Morton
2 siblings, 1 reply; 8+ messages in thread
From: Randy Dunlap @ 2018-07-06 17:48 UTC (permalink / raw)
To: Chris Wilson, linux-kernel
Cc: Jani Nikula, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
On 07/06/18 02:44, Chris Wilson wrote:
> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Andy Gospodarek <gospo@broadcom.com>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Ingo Molnar <mingo@kernel.org>
> ---
> include/linux/bitops.h | 3 ++-
> include/linux/net_dim.h | 1 -
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> index 4cac4e1a72ff..091cb17d1a9b 100644
> --- a/include/linux/bitops.h
> +++ b/include/linux/bitops.h
> @@ -11,7 +11,8 @@
> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
> #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
> #define BITS_PER_BYTE 8
> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
> +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
> #endif
>
> /*
doesn't <linux/net_dim.h> need to #include <linux/bitops.h> ?
> diff --git a/include/linux/net_dim.h b/include/linux/net_dim.h
> index 29ed8fd6379a..14f1734e740a 100644
> --- a/include/linux/net_dim.h
> +++ b/include/linux/net_dim.h
> @@ -326,7 +326,6 @@ static inline void net_dim_sample(u16 event_ctr,
> }
>
> #define NET_DIM_NEVENTS 64
> -#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> #define BIT_GAP(bits, end, start) ((((end) - (start)) + BIT_ULL(bits)) & (BIT_ULL(bits) - 1))
>
> static inline void net_dim_calc_stats(struct net_dim_sample *start,
>
--
~Randy
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 17:48 ` Randy Dunlap
@ 2018-07-06 17:51 ` Chris Wilson
2018-07-06 17:55 ` Randy Dunlap
0 siblings, 1 reply; 8+ messages in thread
From: Chris Wilson @ 2018-07-06 17:51 UTC (permalink / raw)
To: Randy Dunlap, linux-kernel
Cc: Jani Nikula, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
Quoting Randy Dunlap (2018-07-06 18:48:55)
>
> On 07/06/18 02:44, Chris Wilson wrote:
> > net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
> > number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
> > macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
> >
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Cc: Andy Gospodarek <gospo@broadcom.com>
> > Cc: David S. Miller <davem@davemloft.net>
> > Cc: Thomas Gleixner <tglx@linutronix.de>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > Cc: Ingo Molnar <mingo@kernel.org>
> > ---
> > include/linux/bitops.h | 3 ++-
> > include/linux/net_dim.h | 1 -
> > 2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> > index 4cac4e1a72ff..091cb17d1a9b 100644
> > --- a/include/linux/bitops.h
> > +++ b/include/linux/bitops.h
> > @@ -11,7 +11,8 @@
> > #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
> > #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
> > #define BITS_PER_BYTE 8
> > -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
> > +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> > +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
> > #endif
> >
> > /*
>
> doesn't <linux/net_dim.h> need to #include <linux/bitops.h> ?
It already has to in order to obtain BITS_PER_BYTE. Just doesn't do so
directly.
-Chris
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 17:51 ` Chris Wilson
@ 2018-07-06 17:55 ` Randy Dunlap
2018-07-06 18:00 ` Chris Wilson
0 siblings, 1 reply; 8+ messages in thread
From: Randy Dunlap @ 2018-07-06 17:55 UTC (permalink / raw)
To: Chris Wilson, linux-kernel
Cc: Jani Nikula, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
On 07/06/18 10:51, Chris Wilson wrote:
> Quoting Randy Dunlap (2018-07-06 18:48:55)
>>
>> On 07/06/18 02:44, Chris Wilson wrote:
>>> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
>>> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
>>> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
>>>
>>> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>>> Cc: Jani Nikula <jani.nikula@linux.intel.com>
>>> Cc: Andy Gospodarek <gospo@broadcom.com>
>>> Cc: David S. Miller <davem@davemloft.net>
>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> Cc: Ingo Molnar <mingo@kernel.org>
>>> ---
>>> include/linux/bitops.h | 3 ++-
>>> include/linux/net_dim.h | 1 -
>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
>>> index 4cac4e1a72ff..091cb17d1a9b 100644
>>> --- a/include/linux/bitops.h
>>> +++ b/include/linux/bitops.h
>>> @@ -11,7 +11,8 @@
>>> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
>>> #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
>>> #define BITS_PER_BYTE 8
>>> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
>>> +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
>>> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
>>> #endif
>>>
>>> /*
>>
>> doesn't <linux/net_dim.h> need to #include <linux/bitops.h> ?
>
> It already has to in order to obtain BITS_PER_BYTE. Just doesn't do so
> directly.
Right. and does that work on all $ARCHes?
Please see Documentation/process/submit-checklist.rst, rule #1:
1) If you use a facility then #include the file that defines/declares
that facility. Don't depend on other header files pulling in ones
that you use.
thanks,
--
~Randy
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 17:55 ` Randy Dunlap
@ 2018-07-06 18:00 ` Chris Wilson
2018-07-06 18:38 ` Randy Dunlap
0 siblings, 1 reply; 8+ messages in thread
From: Chris Wilson @ 2018-07-06 18:00 UTC (permalink / raw)
To: Randy Dunlap, linux-kernel
Cc: Jani Nikula, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
Quoting Randy Dunlap (2018-07-06 18:55:57)
> On 07/06/18 10:51, Chris Wilson wrote:
> > Quoting Randy Dunlap (2018-07-06 18:48:55)
> >>
> >> On 07/06/18 02:44, Chris Wilson wrote:
> >>> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
> >>> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
> >>> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
> >>>
> >>> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> >>> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> >>> Cc: Andy Gospodarek <gospo@broadcom.com>
> >>> Cc: David S. Miller <davem@davemloft.net>
> >>> Cc: Thomas Gleixner <tglx@linutronix.de>
> >>> Cc: Andrew Morton <akpm@linux-foundation.org>
> >>> Cc: Ingo Molnar <mingo@kernel.org>
> >>> ---
> >>> include/linux/bitops.h | 3 ++-
> >>> include/linux/net_dim.h | 1 -
> >>> 2 files changed, 2 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
> >>> index 4cac4e1a72ff..091cb17d1a9b 100644
> >>> --- a/include/linux/bitops.h
> >>> +++ b/include/linux/bitops.h
> >>> @@ -11,7 +11,8 @@
> >>> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
> >>> #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
> >>> #define BITS_PER_BYTE 8
> >>> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
> >>> +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
> >>> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
> >>> #endif
> >>>
> >>> /*
> >>
> >> doesn't <linux/net_dim.h> need to #include <linux/bitops.h> ?
> >
> > It already has to in order to obtain BITS_PER_BYTE. Just doesn't do so
> > directly.
>
> Right. and does that work on all $ARCHes?
It's a pre-existing dependency in the header, net_dim.h cannot
compile unless BITS_PER_BYTE is defined i.e. bitops.h is included.
The patch does not affect that.
-Chris
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 18:00 ` Chris Wilson
@ 2018-07-06 18:38 ` Randy Dunlap
0 siblings, 0 replies; 8+ messages in thread
From: Randy Dunlap @ 2018-07-06 18:38 UTC (permalink / raw)
To: Chris Wilson, linux-kernel
Cc: Jani Nikula, Andy Gospodarek, David S . Miller, Thomas Gleixner,
Andrew Morton, Ingo Molnar
On 07/06/18 11:00, Chris Wilson wrote:
> Quoting Randy Dunlap (2018-07-06 18:55:57)
>> On 07/06/18 10:51, Chris Wilson wrote:
>>> Quoting Randy Dunlap (2018-07-06 18:48:55)
>>>>
>>>> On 07/06/18 02:44, Chris Wilson wrote:
>>>>> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
>>>>> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
>>>>> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
>>>>>
>>>>> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>>>>> Cc: Jani Nikula <jani.nikula@linux.intel.com>
>>>>> Cc: Andy Gospodarek <gospo@broadcom.com>
>>>>> Cc: David S. Miller <davem@davemloft.net>
>>>>> Cc: Thomas Gleixner <tglx@linutronix.de>
>>>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>>>> Cc: Ingo Molnar <mingo@kernel.org>
>>>>> ---
>>>>> include/linux/bitops.h | 3 ++-
>>>>> include/linux/net_dim.h | 1 -
>>>>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/include/linux/bitops.h b/include/linux/bitops.h
>>>>> index 4cac4e1a72ff..091cb17d1a9b 100644
>>>>> --- a/include/linux/bitops.h
>>>>> +++ b/include/linux/bitops.h
>>>>> @@ -11,7 +11,8 @@
>>>>> #define BIT_ULL_MASK(nr) (1ULL << ((nr) % BITS_PER_LONG_LONG))
>>>>> #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG)
>>>>> #define BITS_PER_BYTE 8
>>>>> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
>>>>> +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
>>>>> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
>>>>> #endif
>>>>>
>>>>> /*
>>>>
>>>> doesn't <linux/net_dim.h> need to #include <linux/bitops.h> ?
>>>
>>> It already has to in order to obtain BITS_PER_BYTE. Just doesn't do so
>>> directly.
>>
>> Right. and does that work on all $ARCHes?
>
> It's a pre-existing dependency in the header, net_dim.h cannot
> compile unless BITS_PER_BYTE is defined i.e. bitops.h is included.
> The patch does not affect that.
Yes, I see. net_dim.h should have #included bits.h and/or bitops.h previously.
thanks,
--
~Randy
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH] bitops: Introduce BITS_PER_TYPE
2018-07-06 9:44 [PATCH] bitops: Introduce BITS_PER_TYPE Chris Wilson
2018-07-06 10:03 ` Jani Nikula
2018-07-06 17:48 ` Randy Dunlap
@ 2018-07-06 21:57 ` Andrew Morton
2 siblings, 0 replies; 8+ messages in thread
From: Andrew Morton @ 2018-07-06 21:57 UTC (permalink / raw)
To: Chris Wilson
Cc: linux-kernel, Jani Nikula, Andy Gospodarek, David S . Miller,
Thomas Gleixner, Ingo Molnar
On Fri, 6 Jul 2018 10:44:58 +0100 Chris Wilson <chris@chris-wilson.co.uk> wrote:
> net_dim.h has a rather useful extension to BITS_PER_BYTE to compute the
> number of bits in a type (BITS_PER_BYTE * sizeof(T)), so promote the
> macro to bitops.h, alongside BITS_PER_BYTE, for wider usage.
A bit of grepping shows that there's quite a lot of code which does
sizeof(blah)*BITS_PER_BYTE. Fun newbie project.
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2018-07-06 21:58 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-07-06 9:44 [PATCH] bitops: Introduce BITS_PER_TYPE Chris Wilson
2018-07-06 10:03 ` Jani Nikula
2018-07-06 17:48 ` Randy Dunlap
2018-07-06 17:51 ` Chris Wilson
2018-07-06 17:55 ` Randy Dunlap
2018-07-06 18:00 ` Chris Wilson
2018-07-06 18:38 ` Randy Dunlap
2018-07-06 21:57 ` Andrew Morton
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.