Re: [PATCH] arm64: cpuinfo: add AArch64 & elf platform for app compatibility

[Xiaqing (A)]

å 2016/5/19 19:04, Robin Murphy åé:
> On 19/05/16 03:44, x00195127 wrote:
> > we find that some apps will read cpuinfo when start up,
> > they need the string  as follows:
> > "Processor       : AArch64 Processor rev 0 (aarch64)"
> >
> > Then thay could load the corresponding libs. But now
> > arm64 platform's cpuinfo don't has this now, so
> > we need add this.
> >
> > Signed-off-by: Qing Xia <saberlily.xia@xxxxxxxxxxxxx>
> > ---
> >   arch/arm64/kernel/cpuinfo.c | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
> > index 3808470..c3527ad 100644
> > --- a/arch/arm64/kernel/cpuinfo.c
> > +++ b/arch/arm64/kernel/cpuinfo.c
> > @@ -114,6 +114,9 @@ static int c_show(struct seq_file *m, void *v)
> >            * online processors, looking for lines beginning with
> >            * "processor".  Give glibc what it expects.
> >            */
> > +        seq_printf(m, "Processor\t: AArch64 Processor rev %d (%s)\n",
> > +                read_cpuid_id() & 15, ELF_PLATFORM);
>
> The pre-3.19 behaviour printed this once - now you're printing it for
> every CPU in the system, but all with the same revision of whichever
> core this happens to be running on, which is unjustifiably incorrect.
>
> Furthermore, this string provides virtually no useful information anyway
> - the majority of code running on AArch64 already knows that by virtue
> of the fact that *it's running at all*, and for scripts/interpreted
> code/etc. there are already appropriate mechanisms for discovering the
> platform (e.g. uname).
>
> Robin.

Those are 32-bit andriod apps, and according to my tests they really 
need this information, although this information is already useless in 
my opinion. A lot of android apps update very slowly.

> > +
> >           seq_printf(m, "processor\t: %d\n", i);
> >
> >           seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
>
>
> .