Re: [PATCH] scripts/faddr2line: show the code context

[Du, Changbin]

On Wed, May 30, 2018 at 08:01:48AM +1000, NeilBrown wrote:
> On Tue, May 29 2018, Peter Zijlstra wrote:
> 
> > On Tue, May 29, 2018 at 12:07:10PM -0500, Josh Poimboeuf wrote:
> >> Yeah, this change really should have been an optional arg.  It hurt the
> >> readability and compactness of the output.  The above looks good to me.
> >> 
> >> Care to send a proper patch?  If you send it to Linus he might apply it
> >> directly as he did with my original patches.
> >
> > ---
> > From: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxx>
> >
> > Commit 6870c0165feaa5 ("scripts/faddr2line: show the code context")
> > radically altered the output format of the faddr2line tool. And while
> > the new list output format might have merrit it broke my vim usage and
> > was hard to read.
> >
> > Make the new format optional; using a '--list' argument and attempt to
> > make the output slightly easier to read by adding a little whitespace to
> > separate the different files and explicitly mark the line in question.
> 
> Not commenting on your code but on the original patch.....
> I've recently noticed that ADDR2LINE sometimes outputs
>   (discriminator 2)
> or similar at the end of the line.  This messes up the parsing.
> 
> I hacked it to work so I could keep debugging with
> 
> -		local file_lines=$(${ADDR2LINE} -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;")
> +		local file_lines=$(${ADDR2LINE} -fpie $objfile $addr | sed -e "s; $dir_prefix\(\./\)*; ;" -e "s/(discriminator [0-9]*)//")
> 
> but someone should probably find out exactly what sort of messages
> ADDR2LINE produces, and make sure they are all parsed correctly.
> (maybe that someone should be me, but not today).
> 
Hi, I have fixed it by commit 78eb0c6356 ("scripts/faddr2line: fix error when
addr2line output contains discriminator") and it is already in the mainline now.
Thank you!

> Thanks,
> NeilBrown
> 
> 
> >
> > Cc: Changbin Du <changbin.du@xxxxxxxxx>
> > Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> > Fixes: 6870c0165feaa5 ("scripts/faddr2line: show the code context")
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> > ---
> >  scripts/faddr2line | 18 ++++++++++++++++--
> >  1 file changed, 16 insertions(+), 2 deletions(-)
> >
> > diff --git a/scripts/faddr2line b/scripts/faddr2line
> > index 1876a741087c..a0149db00be7 100755
> > --- a/scripts/faddr2line
> > +++ b/scripts/faddr2line
> > @@ -56,7 +56,7 @@ command -v ${SIZE} >/dev/null 2>&1 || die "size isn't installed"
> >  command -v ${NM} >/dev/null 2>&1 || die "nm isn't installed"
> >  
> >  usage() {
> > -	echo "usage: faddr2line <object file> <func+offset> <func+offset>..." >&2
> > +	echo "usage: faddr2line [--list] <object file> <func+offset> <func+offset>..." >&2
> >  	exit 1
> >  }
> >  
> > @@ -166,15 +166,25 @@ __faddr2line() {
> >  		local file_lines=$(${ADDR2LINE} -fpie $objfile $addr | sed "s; $dir_prefix\(\./\)*; ;")
> >  		[[ -z $file_lines ]] && return
> >  
> > +		if [[ $LIST = 0 ]]; then
> > +			echo "$file_lines" | while read -r line
> > +			do
> > +				echo $line
> > +			done
> > +			DONE=1;
> > +			return
> > +		fi
> > +
> >  		# show each line with context
> >  		echo "$file_lines" | while read -r line
> >  		do
> > +			echo
> >  			echo $line
> >  			n=$(echo $line | sed 's/.*:\([0-9]\+\).*/\1/g')
> >  			n1=$[$n-5]
> >  			n2=$[$n+5]
> >  			f=$(echo $line | sed 's/.*at \(.\+\):.*/\1/g')
> > -			awk 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") {printf("%d\t%s\n", NR, $0)}' $f
> > +			awk 'NR>=strtonum("'$n1'") && NR<=strtonum("'$n2'") { if (NR=='$n') printf(">%d<", NR); else printf(" %d ", NR); printf("\t%s\n", $0)}' $f
> >  		done
> >  
> >  		DONE=1
> > @@ -185,6 +195,10 @@ __faddr2line() {
> >  [[ $# -lt 2 ]] && usage
> >  
> >  objfile=$1
> > +
> > +LIST=0
> > +[[ "$objfile" == "--list" ]] && LIST=1 && shift && objfile=$1
> > +
> >  [[ ! -f $objfile ]] && die "can't find objfile $objfile"
> >  shift
> >  



-- 
Thanks,
Changbin Du