RE: [PATCH] perf test: Fix shadow stat test for non-bash shells

[David Laight <David.Laight@ACULAB.COM>]

From: Jiri Olsa
> Sent: 12 January 2021 09:30
> 
> On Fri, Jan 08, 2021 at 04:47:12PM +0900, Namhyung Kim wrote:
> > It was using some bash-specific features and failed to parse when
> > running with a different shell like below:
...

You don't need a temporary file, one option is:

> > index 249dfe48cf6a..e2c7ac4ed91d 100755
> > --- a/tools/perf/tests/shell/stat+shadow_stat.sh
> > +++ b/tools/perf/tests/shell/stat+shadow_stat.sh
...
> >  	perf stat -a -A --no-big-num -e cycles,instructions sleep 1  2>&1 | \
> >  	grep ^CPU | \
> >  	while read cpu num evt hash ipc rest
> >  	do
...
> > +		if [ "$evt" = "cycles" ]; then
> > +			echo $cpu $num >> $results

			results="$results $cpu:$num"

> >  			continue
> >  		fi
> >
> >  		# skip if no cycles
> > -		local cyc=${results[$cpu]}
> > -		if [[ -z $cyc ]]; then
> > +		local cyc=$(grep $cpu $results | cut -d' ' -f2)

		cyc=${results##* $cpu:}
		cyc=$(cyc%% *}

> > +		if [ -z "$cyc" ]; then
> >  			continue
> >  		fi

I can't remember when 'local' was invented.
You may find shells that don't support it.
In any case, since this is a small standalone file I'd
remove them just in case.

	David

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