The current version of "perf buildid-list" prints missing build-ids as blank even when loading perf.data files generated from older versions of perf. I've tested with a few older versions.
Since perf-archive is an external script that calls back into perf, it could in theory find a different older version that still returns zeroes. We could make it look for a matching perf, e.g. "$(dirname "$0")/perf". Unfortunately that won't work in general because at least on my system perf-archive is installed to a different path than perf. Nick On 2021-02-12 7:29 a.m., Arnaldo Carvalho de Melo wrote: > Em Wed, Feb 10, 2021 at 02:17:49PM -0500, Nicholas Fraser escreveu: >> A non-existent build-id used to be treated as all-zero SHA-1 hash. >> Build-ids are now variable width. A non-existent build-id is an empty >> string and "perf buildid-list" pads this with spaces. >> >> This fixes "perf-archive" to skip missing build-ids by skipping lines >> that start with a padding space rather than with zeroes. >> >> Signed-off-by: Nicholas Fraser <[email protected]> >> --- >> tools/perf/perf-archive.sh | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/tools/perf/perf-archive.sh b/tools/perf/perf-archive.sh >> index 0cfb3e2cefef..133f0eddbcc4 100644 >> --- a/tools/perf/perf-archive.sh >> +++ b/tools/perf/perf-archive.sh >> @@ -20,9 +20,8 @@ else >> fi >> >> BUILDIDS=$(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 > > What should we do when using older files? We have to support both cases. > > - Arnaldo >
