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Date: Wed, 22 Nov 2017 09:32:20 +0100
From: Jiri Olsa <jolsa@redhat.com>
To: "Jin, Yao" <yao.jin@linux.intel.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>, acme@kernel.org,
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        alexander.shishkin@linux.intel.com, Linux-kernel@vger.kernel.org,
        ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com
Subject: Re: [PATCH v1 3/9] perf util: Reconstruct rblist for supporting
 per-thread shadow stats
Message-ID: <20171122083220.GC30707@krava>
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On Wed, Nov 22, 2017 at 02:57:12PM +0800, Jin, Yao wrote:
> 
> 
> On 11/22/2017 2:31 PM, Ravi Bangoria wrote:
> > 
> > On 11/20/2017 08:13 PM, Jin Yao wrote:
> > > @@ -76,6 +97,17 @@ static struct rb_node *saved_value_new(struct
> > > rblist *rblist __maybe_unused,
> > >       return &nd->rb_node;
> > >   }
> > > 
> > > +static void saved_value_delete(struct rblist *rblist __maybe_unused,
> > > +                   struct rb_node *rb_node)
> > > +{
> > > +    struct saved_value *v = container_of(rb_node,
> > > +                         struct saved_value,
> > > +                         rb_node);
> > > +
> > > +    if (v)
> > > +        free(v);
> > > +}
> > 
> > Do we really need if(v) ?
> > 
> > Thanks,
> > Ravi
> > 
> 
> Hi Ravi,
> 
> Looks it doesn't need if(v).
> 
> I put if(v) here is from my coding habits (checking pointer before free).
> 
> It's OK for me if you think the code should be removed.

you could add BUG_ON(!rb_node);

jirka