Re: [tip:x86/cpu] x86: cacheinfo: replace sysfs interface for cache_disable feature

[Jaswinder Singh Rajput <jaswinder@kernel.org>]

On Tue, 2009-04-14 at 13:58 +0200, Ingo Molnar wrote:
> * Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:
> 
> > On Mon, 2009-04-13 at 10:22 +0530, Jaswinder Singh Rajput wrote:
> > > Hello Mark,
> > > 
> > > On Fri, 2009-04-10 at 12:37 +0000, Mark Langsdorf wrote:
> > > > Commit-ID:  f8b201fc7110c3673437254e8ba02451461ece0b
> > > > Gitweb:     http://git.kernel.org/tip/f8b201fc7110c3673437254e8ba02451461ece0b
> > > > Author:     Mark Langsdorf <mark.langsdorf@amd.com>
> > > > AuthorDate: Thu, 9 Apr 2009 15:18:49 +0200
> > > > Committer:  Ingo Molnar <mingo@elte.hu>
> > > > CommitDate: Fri, 10 Apr 2009 14:21:53 +0200
> > > > 
> > > > x86: cacheinfo: replace sysfs interface for cache_disable feature
> > > > 
> > > > Impact: replace sysfs attribute
> > > > 
> > > > Current interface violates against "one-value-per-sysfs-attribute
> > > > rule". This patch replaces current attribute with two attributes --
> > > > one for each L3 Cache Index Disable register.
> > > > 
> > > > Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
> > > > Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
> > > > Cc: Andrew Morton <akpm@linux-foundation.org>
> > > > LKML-Reference: <20090409131849.GJ31527@alberich.amd.com>
> > > > Signed-off-by: Ingo Molnar <mingo@elte.hu>
> > > > 
> > > > 
> > > > ---
> > > >  arch/x86/kernel/cpu/intel_cacheinfo.c |   90 ++++++++++++++++----------------
> > > >  1 files changed, 45 insertions(+), 45 deletions(-)
> > > > 
> > > > diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
> > > > index 0cde071..fc28291 100644
> > > > --- a/arch/x86/kernel/cpu/intel_cacheinfo.c
> > > > +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
> > > > @@ -697,73 +697,69 @@ static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf)
> > > >  #define to_object(k)	container_of(k, struct _index_kobject, kobj)
> > > >  #define to_attr(a)	container_of(a, struct _cache_attr, attr)
> > > >  
> > > > -static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf)
> > > > +static ssize_t show_cache_disable(struct _cpuid4_info *this_leaf, char *buf,
> > > > +				  unsigned int index)
> > > >  {
> > > > -	const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
> > > > -	int node = cpu_to_node(cpumask_first(mask));
> > > > -	struct pci_dev *dev = NULL;
> > > > -	ssize_t ret = 0;
> > > > -	int i;
> > > > +	int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
> > > > +	int node = cpu_to_node(cpu);
> > > > +	struct pci_dev *dev = node_to_k8_nb_misc(node);
> > > > +	unsigned int reg = 0;
> > > 
> > > This leads to compilation warnings:
> > >   CC      arch/x86/kernel/cpu/intel_cacheinfo.o
> > > arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘show_cache_disable’:
> > > arch/x86/kernel/cpu/intel_cacheinfo.c:712: warning: unused variable ‘node’
> > > 
> > > >  
> > > > -static ssize_t
> > > > -store_cache_disable(struct _cpuid4_info *this_leaf, const char *buf,
> > > > -		    size_t count)
> > > > +static ssize_t store_cache_disable(struct _cpuid4_info *this_leaf,
> > > > +	const char *buf, size_t count, unsigned int index)
> > > >  {
> > > > -	const struct cpumask *mask = to_cpumask(this_leaf->shared_cpu_map);
> > > > -	int node = cpu_to_node(cpumask_first(mask));
> > > > -	struct pci_dev *dev = NULL;
> > > > -	unsigned int ret, index, val;
> > > > +	int cpu = cpumask_first(to_cpumask(this_leaf->shared_cpu_map));
> > > > +	int node = cpu_to_node(cpu);
> > > > +	struct pci_dev *dev = node_to_k8_nb_misc(node);
> > > > +	unsigned long val = 0;
> > > >  
> > > 
> > >   CC      arch/x86/kernel/cpu/intel_cacheinfo.o
> > > arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘store_cache_disable’:
> > > arch/x86/kernel/cpu/intel_cacheinfo.c:737: warning: unused variable ‘cpu’
> > 
> > Oops it is also pointing to node:
> > 
> > arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘store_cache_disable’:
> > arch/x86/kernel/cpu/intel_cacheinfo.c:739: warning: unused variable ‘node’
> 
> Mind sending a fix? We really dont want warnings noise in the x86 
> tree.
> 

Ok I send it.

when I fixed node then it gives warnings for :
  arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘show_cache_disable’:
  arch/x86/kernel/cpu/intel_cacheinfo.c:713: warning: unused variable ‘cpu’

So I also fixed it.


> I was also thinking about adopting the Sparc trick: adding -Werror 
> to arch/x86/ files only, fixing all the fallout and ensuring no new 
> warnings from a flag day on. Anyone interested in doing that?
> 

Yes, this will be nice idea. Should I send patch for:
"adding -Werror to arch/x86/ files only"

Thanks,
--
JSR