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Date:   Fri, 29 Oct 2021 16:25:49 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Kalesh Singh <kaleshsingh@google.com>
Cc:     surenb@google.com, hridya@google.com, namhyung@kernel.org,
        kernel-team@android.com, mhiramat@kernel.org,
        Jonathan Corbet <corbet@lwn.net>,
        Ingo Molnar <mingo@redhat.com>, Shuah Khan <shuah@kernel.org>,
        Tom Zanussi <zanussi@kernel.org>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v2 1/4] tracing/histogram: Optimize division by
 constants
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On Fri, 29 Oct 2021 11:53:16 -0700
Kalesh Singh <kaleshsingh@google.com> wrote:

> > If these functions are only called when val2 is constant, can't we make it
> > such that we get val2 from the hist_field directly? That is:
> >
> >         u64 val2 = operand2->constant;  
> 
> operand2 might be a var ref to a constant, so we would need to resolve
> that with hist_field_var_ref().

So can a var_ref change? If not, then we should convert that to a constant
for this operation.

-- Steve