Re: [PATCH] interconnect: Add basic tracepoints

From: Steven Rostedt <rostedt@goodmis.org>
To: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Georgi Djakov <georgi.djakov@linaro.org>,
	linux-pm@vger.kernel.org, mingo@redhat.com,
	vincent.guittot@linaro.org, daidavid1@codeaurora.org,
	okukatla@codeaurora.org, evgreen@chromium.org, mka@chromium.org,
	linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] interconnect: Add basic tracepoints
Date: Fri, 18 Oct 2019 12:55:50 -0400	[thread overview]
Message-ID: <20191018125550.0ad0eefa@gandalf.local.home> (raw)
In-Reply-To: <20191018164403.GB1669@tuxbook-pro>

On Fri, 18 Oct 2019 09:44:03 -0700
Bjorn Andersson <bjorn.andersson@linaro.org> wrote:

> > @@ -449,6 +452,9 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw)
> >  
> >  		/* aggregate requests for this node */
> >  		aggregate_requests(node);
> > +
> > +		trace_icc_set_bw(node, dev_name(path->reqs[i].dev),
> > +				 avg_bw, peak_bw);  
> 
> When I've been debugging interconnect things I've added a
> kstrdup_const() of "name" in of_icc_get() and then included that here.
> 
> I find including the path name quite useful for devices with multiple
> paths.
> 
> >  	}
> >  
> >  	ret = apply_constraints(path);
> > @@ -461,6 +467,9 @@ int icc_set_bw(struct icc_path *path, u32 avg_bw, u32 peak_bw)
> >  			path->reqs[i].avg_bw = old_avg;
> >  			path->reqs[i].peak_bw = old_peak;
> >  			aggregate_requests(node);
> > +
> > +			trace_icc_set_bw(node, dev_name(path->reqs[i].dev),
> > +					 old_avg, old_peak);
> >  		}
> >  		apply_constraints(path);  
> 
> And analog to e.g. the clock traces I would suggest that you trace
> device, path and "ret" here.

If you are going to switch to device name and path, please just pass in
the path to the trace point. Then have the TP_fast_assign() do the rest
of the work.

Thanks!

-- Steve