Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls

From	Jacob Pan <jacob.jun.pan@linux.intel.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls
Date	2016-01-13 17:30 +0100
Message-ID	<qQwt5-2jv-27@gated-at.bofh.it> (permalink)
References	<qQigq-HG-9@gated-at.bofh.it> <qQigq-HG-11@gated-at.bofh.it> <qQqe0-6f4-39@gated-at.bofh.it>
Organization	OTC

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On Wed, 13 Jan 2016 10:47:26 +0100 (CET)
Thomas Gleixner <tglx@linutronix.de> wrote:

> So here you actually use that new (misnomed) function, but for 
> 
> > +static void power_limit_irq_save_cpu(void *info)  
> 
> and
> 
> > +static void power_limit_irq_restore_cpu(void *info)  
> 
> you use a bog standard smp function call. What's the benefit of
> adding that rmw function over a bog standard smp function call if you
> can only use it for one instance of the same pattern?
> 
> Boris asked you the same question here
> 
>       https://lkml.kernel.org/r/20151220152749.GA29805@pd.tnic
> 
> but you decided to ignore it.
+Borislav,

Thanks for bring this out. I didn't mean to ignore. I thought my point
was stated in the commit message there was no point of going back and
forth. Read-Modify-Write is quite common, not just for RAPL could be
used by future code. Sorry if I wasn't clear.

Jacob

Thread

[PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 02:20 +0100
  Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Thomas Gleixner <tglx@linutronix.de> - 2016-01-13 10:50 +0100
    Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 17:30 +0100
      Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 17:40 +0100
        Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 19:00 +0100
          Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 19:10 +0100
            Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 19:30 +0100
              Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 20:20 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 21:20 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 22:30 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> - 2016-01-13 23:00 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Thomas Gleixner <tglx@linutronix.de> - 2016-01-13 23:10 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 23:20 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls "H. Peter Anvin" <hpa@zytor.com> - 2016-01-13 23:30 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 23:20 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> - 2016-01-13 23:50 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Jacob Pan <jacob.jun.pan@linux.intel.com> - 2016-01-13 23:30 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Borislav Petkov <bp@alien8.de> - 2016-01-13 23:30 +0100
                Re: [PATCH v2 2/2] powercap/rapl: reduce ipi calls Thomas Gleixner <tglx@linutronix.de> - 2016-01-13 23:00 +0100

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