perf config: Document 'buildid.dir' variable in man page

Explain 'buildid.dir' variable.

Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1452253193-30502-4-git-send-email-treeze.taeung@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt
index ccbdb64696a792f9b3786ab1092bd8f5d5e30fbc..a095f0cabf5e208352c0386047b4a25d62d4c1bd 100644 (file)
--- a/tools/perf/Documentation/perf-config.txt
+++ b/tools/perf/Documentation/perf-config.txt
@@ -154,6 +154,21 @@ tui.*, gtk.*::
        will make the TUI be the default for the 'top' subcommand. Those will be
        available if the required libs were detected at tool build time.
 
+buildid.*::
+       buildid.dir::
+               Each executable and shared library in modern distributions comes with a
+               content based identifier that, if available, will be inserted in a
+               'perf.data' file header to, at analysis time find what is needed to do
+               symbol resolution, code annotation, etc.
+
+               The recording tools also stores a hard link or copy in a per-user
+               directory, $HOME/.debug/, of binaries, shared libraries, /proc/kallsyms
+               and /proc/kcore files to be used at analysis time.
+
+               The buildid.dir variable can be used to either change this directory
+               cache location, or to disable it altogether. If you want to disable it,
+               set buildid.dir to /dev/null. The default is $HOME/.debug
+
 SEE ALSO
 --------
 linkperf:perf[1]