Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-10-01 Thread Shivraj Patil 

On Wed, Sep 30, 2015 at 02:21:18PM +, Shivraj Patil wrote:
> 
> On Wed, Sep 30, 2015 at 07:03:46PM +0530, shivraj.pa...@imgtec.com wrote:
> > From: Shivraj Patil 
> [...]
> 
> > +static int get_cpuinfo(uint32_t *hwcap) {
> > +FILE *f = fopen("/proc/cpuinfo", "r");
> 
> under qemu i get this:
> 
> cpu_flags(raw) = 0x
> cpu_flags_str(raw) =
> cpu_flags(effective) = 0x
> cpu_flags_str(effective) =
> threads = 1 (cpu_count = 12)
> 
> IIUC this disables all cpu extensions
> is that intended ?
> (we currently only have loongson hardware to test so this would mean  
> an end to testing imgtec specific mips optimizations)
> 
> Shivraj:- cpu detection will not work for qemu, however we have tested it on 
> mips hardware at our end.

iam not speaking about just this patch
but we have just qemu to test on imgtec - mips i can apply this patch but it 
means that in the future FFmpeg will then only be tested on loongson because 
you effectively disable our only way to test code on imgtec mips

its very strange that you want this

Shivraj:- I have got the concern with this patch and so request you to please 
discard it for now.
It will make more sense to resubmit (modified) at appropriate time in near 
future when MSA enabled devices are setup for testing.
Till the time requesting to keep the mips testing under QEMU as it is.

[...]
-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

You can kill me, but you cannot change the truth.
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Michael Niedermayer 
On Wed, Sep 30, 2015 at 02:21:18PM +, Shivraj Patil wrote:
> 
> On Wed, Sep 30, 2015 at 07:03:46PM +0530, shivraj.pa...@imgtec.com wrote:
> > From: Shivraj Patil 
> [...]
> 
> > +static int get_cpuinfo(uint32_t *hwcap) {
> > +FILE *f = fopen("/proc/cpuinfo", "r");
> 
> under qemu i get this:
> 
> cpu_flags(raw) = 0x
> cpu_flags_str(raw) =
> cpu_flags(effective) = 0x
> cpu_flags_str(effective) =
> threads = 1 (cpu_count = 12)
> 
> IIUC this disables all cpu extensions
> is that intended ?
> (we currently only have loongson hardware to test so this would mean  an end 
> to testing imgtec specific mips optimizations)
> 
> Shivraj:- cpu detection will not work for qemu, however we have tested it on 
> mips hardware at our end.

iam not speaking about just this patch
but we have just qemu to test on imgtec - mips
i can apply this patch but it means that in the future FFmpeg
will then only be tested on loongson because you effectively disable
our only way to test code on imgtec mips

its very strange that you want this


[...]
-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

You can kill me, but you cannot change the truth.


signature.asc
Description: Digital signature
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Clément Bœsch 
On Wed, Sep 30, 2015 at 02:23:43PM +, Shivraj Patil wrote:
> 
>   imgtec.com> writes:
> 
> > +FILE *f = fopen("/proc/cpuinfo", "r");
> 
> Is this what every other software for mips does?
> How does the kernel (or whatever sets cpuinfo) know?
> 
> Shivraj:- We have used generic cpuinfo as it is unrestricted to access from 
> user space compared to the kernel setting hwcaps (via low level mips control 
> regs accessible) in kernel space for now. 
> 

I might be asking something stupid, but afaik /proc is linux exclusive;
does this mean it's going to disable all optimisations on every other
system?

[...]

-- 
Clément B.


signature.asc
Description: PGP signature
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Carl Eugen Hoyos 
  imgtec.com> writes:

> +FILE *f = fopen("/proc/cpuinfo", "r");

Is this what every other software for mips does?
How does the kernel (or whatever sets cpuinfo) know?

Carl Eugen

___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Shivraj Patil 

On Wed, Sep 30, 2015 at 07:03:46PM +0530, shivraj.pa...@imgtec.com wrote:
> From: Shivraj Patil 
[...]

> +static int get_cpuinfo(uint32_t *hwcap) {
> +FILE *f = fopen("/proc/cpuinfo", "r");

under qemu i get this:

cpu_flags(raw) = 0x
cpu_flags_str(raw) =
cpu_flags(effective) = 0x
cpu_flags_str(effective) =
threads = 1 (cpu_count = 12)

IIUC this disables all cpu extensions
is that intended ?
(we currently only have loongson hardware to test so this would mean  an end to 
testing imgtec specific mips optimizations)

Shivraj:- cpu detection will not work for qemu, however we have tested it on 
mips hardware at our end.

[...]
-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Avoid a single point of failure, be that a person or equipment.
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Michael Niedermayer 
On Wed, Sep 30, 2015 at 07:03:46PM +0530, shivraj.pa...@imgtec.com wrote:
> From: Shivraj Patil 
[...]

> +static int get_cpuinfo(uint32_t *hwcap)
> +{
> +FILE *f = fopen("/proc/cpuinfo", "r");

under qemu i get this:

cpu_flags(raw) = 0x
cpu_flags_str(raw) =
cpu_flags(effective) = 0x
cpu_flags_str(effective) =
threads = 1 (cpu_count = 12)

IIUC this disables all cpu extensions
is that intended ?
(we currently only have loongson hardware to test so this would mean
 an end to testing imgtec specific mips optimizations)

[...]
-- 
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Avoid a single point of failure, be that a person or equipment.


signature.asc
Description: Digital signature
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Re: [FFmpeg-devel] [PATCH] avutil: runtime cpu detection for mips

2015-09-30 Thread Shivraj Patil 

  imgtec.com> writes:

> +FILE *f = fopen("/proc/cpuinfo", "r");

Is this what every other software for mips does?
How does the kernel (or whatever sets cpuinfo) know?

Shivraj:- We have used generic cpuinfo as it is unrestricted to access from 
user space compared to the kernel setting hwcaps (via low level mips control 
regs accessible) in kernel space for now. 

Thanks,

Carl Eugen

___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
___
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel