[PATCH 1/2] perf archive: Fix filtering of empty build-ids

[PATCH 1/2] perf archive: Fix filtering of empty build-ids

[Nicholas Fraser]

A non-existent build-id used to be treated as all-zero SHA-1 hash.
Build-ids are now variable width. A non-existent build-id is an empty
string and "perf buildid-list" pads this with spaces. This is true even
when using old perf.data files recorded from older versions of perf;
"perf buildid-list" never reports an all-zero hash anymore.

This fixes "perf-archive" to skip missing build-ids by skipping lines
that start with a padding space rather than with zeroes.

Signed-off-by: Nicholas Fraser <nfraser@codeweavers.com>
---
 tools/perf/perf-archive.sh | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tools/perf/perf-archive.sh b/tools/perf/perf-archive.sh
index 0cfb3e2cefef..133f0eddbcc4 100644
--- a/tools/perf/perf-archive.sh
+++ b/tools/perf/perf-archive.sh
@@ -20,9 +20,8 @@ else
 fi
 
 BUILDIDS=$(mktemp /tmp/perf-archive-buildids.XXXXXX)
-NOBUILDID=0000000000000000000000000000000000000000
 
-perf buildid-list -i $PERF_DATA --with-hits | grep -v "^$NOBUILDID " > $BUILDIDS
+perf buildid-list -i $PERF_DATA --with-hits | grep -v "^ " > $BUILDIDS
 if [ ! -s $BUILDIDS ] ; then
 	echo "perf archive: no build-ids found"
 	rm $BUILDIDS || true
-- 
2.30.1

Re: [PATCH 1/2] perf archive: Fix filtering of empty build-ids

[Jiri Olsa]

On Fri, Feb 19, 2021 at 11:09:32AM -0500, Nicholas Fraser wrote:
> A non-existent build-id used to be treated as all-zero SHA-1 hash.
> Build-ids are now variable width. A non-existent build-id is an empty
> string and "perf buildid-list" pads this with spaces. This is true even
> when using old perf.data files recorded from older versions of perf;
> "perf buildid-list" never reports an all-zero hash anymore.
> 
> This fixes "perf-archive" to skip missing build-ids by skipping lines
> that start with a padding space rather than with zeroes.
> 
> Signed-off-by: Nicholas Fraser <nfraser@codeweavers.com>

Acked-by: Jiri Olsa <jolsa@redhat.com>

thanks,
jirka

> ---
>  tools/perf/perf-archive.sh | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/tools/perf/perf-archive.sh b/tools/perf/perf-archive.sh
> index 0cfb3e2cefef..133f0eddbcc4 100644
> --- a/tools/perf/perf-archive.sh
> +++ b/tools/perf/perf-archive.sh
> @@ -20,9 +20,8 @@ else
>  fi
>  
>  BUILDIDS=$(mktemp /tmp/perf-archive-buildids.XXXXXX)
> -NOBUILDID=0000000000000000000000000000000000000000
>  
> -perf buildid-list -i $PERF_DATA --with-hits | grep -v "^$NOBUILDID " > $BUILDIDS
> +perf buildid-list -i $PERF_DATA --with-hits | grep -v "^ " > $BUILDIDS
>  if [ ! -s $BUILDIDS ] ; then
>  	echo "perf archive: no build-ids found"
>  	rm $BUILDIDS || true
> -- 
> 2.30.1
> 

Re: [PATCH 1/2] perf archive: Fix filtering of empty build-ids

[Arnaldo Carvalho de Melo]

Em Wed, Feb 24, 2021 at 02:50:20PM +0100, Jiri Olsa escreveu:
> On Fri, Feb 19, 2021 at 11:09:32AM -0500, Nicholas Fraser wrote:
> > A non-existent build-id used to be treated as all-zero SHA-1 hash.
> > Build-ids are now variable width. A non-existent build-id is an empty
> > string and "perf buildid-list" pads this with spaces. This is true even
> > when using old perf.data files recorded from older versions of perf;
> > "perf buildid-list" never reports an all-zero hash anymore.
> > 
> > This fixes "perf-archive" to skip missing build-ids by skipping lines
> > that start with a padding space rather than with zeroes.
> > 
> > Signed-off-by: Nicholas Fraser <nfraser@codeweavers.com>
> 
> Acked-by: Jiri Olsa <jolsa@redhat.com>

Thanks, applied.

- Arnaldo

 
> thanks,
> jirka
> 
> > ---
> >  tools/perf/perf-archive.sh | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> > 
> > diff --git a/tools/perf/perf-archive.sh b/tools/perf/perf-archive.sh
> > index 0cfb3e2cefef..133f0eddbcc4 100644
> > --- a/tools/perf/perf-archive.sh
> > +++ b/tools/perf/perf-archive.sh
> > @@ -20,9 +20,8 @@ else
> >  fi
> >  
> >  BUILDIDS=$(mktemp /tmp/perf-archive-buildids.XXXXXX)
> > -NOBUILDID=0000000000000000000000000000000000000000
> >  
> > -perf buildid-list -i $PERF_DATA --with-hits | grep -v "^$NOBUILDID " > $BUILDIDS
> > +perf buildid-list -i $PERF_DATA --with-hits | grep -v "^ " > $BUILDIDS
> >  if [ ! -s $BUILDIDS ] ; then
> >  	echo "perf archive: no build-ids found"
> >  	rm $BUILDIDS || true
> > -- 
> > 2.30.1
> > 
> 

-- 

- Arnaldo