As the buildid is read from /sys/kernel/notes, then if we use perf kvm buildid-list with a perf data file captured by perf kvm record with --guestkallsyms and --guestmodules, there is no result in output. This patch add a explanation about it and add a limit of using perf kvm buildid-list.
Signed-off-by: Dongsheng Yang <[email protected]> --- tools/perf/Documentation/perf-kvm.txt | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/perf/Documentation/perf-kvm.txt b/tools/perf/Documentation/perf-kvm.txt index 830613a..be1d263 100644 --- a/tools/perf/Documentation/perf-kvm.txt +++ b/tools/perf/Documentation/perf-kvm.txt @@ -44,7 +44,9 @@ There are a couple of variants of perf kvm: 'perf kvm buildid-list' to display the buildids found in a perf data file, so that other tools can be used to fetch packages with matching symbol tables - for use by perf report. + for use by perf report. As buildid is read from /sys/kernel/notes in os, then + if you want to list the buildid for guest, please make sure your perf data file + was captured with --guestmount in perf kvm record. 'perf kvm stat <command>' to run a command and gather performance counter statistics. -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
