perf buildid: add perfconfig option to specify buildid cache dir

This patch adds the ability to specify an alternate directory to store the
buildid cache (buildids, copy of binaries). By default, it is hardcoded to
$HOME/.debug. This directory contains immutable data. The layout of the
directory is such that no conflicts in filenames are possible. A modification
in a file, yields a different buildid and thus a different location in the
subdir hierarchy.

You may want to put the buildid cache elsewhere because of disk space
limitation or simply to share the cache between users. It is also useful for
remote collect vs. local analysis of profiles.

This patch adds a new config option to the perfconfig file.  Under the tag
'buildid', there is a dir option. For instance, if you have:

$ cat /etc/perfconfig
[buildid]
dir = /var/cache/perf-buildid

All buildids and binaries are be saved in the directory specified. The perf
record, buildid-list, buildid-cache, report, annotate, and archive commands
will it to pull information out.

The option can be set in the system-wide perfconfig file or in the
$HOME/.perfconfig file.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4c055fb7.df0ce30a.5f0d.ffffae52@mx.google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 15 insertions, 5 deletions

diff --git a/tools/perf/perf-archive.sh b/tools/perf/perf-archive.sh
index 2e7a4f417e20..677e59d62a8d 100644
--- a/tools/perf/perf-archive.sh
+++ b/tools/perf/perf-archive.sh
@@ -7,7 +7,17 @@ if [ $# -ne 0 ] ; then
         PERF_DATA=$1
 fi
 
-DEBUGDIR=~/.debug/
+#
+# PERF_BUILDID_DIR environment variable set by perf
+# path to buildid directory, default to $HOME/.debug
+#
+if [ -z $PERF_BUILDID_DIR ]; then
+        PERF_BUILDID_DIR=~/.debug/
+else
+        # append / to make substitutions work
+        PERF_BUILDID_DIR=$PERF_BUILDID_DIR/
+fi
+
 BUILDIDS=$(mktemp /tmp/perf-archive-buildids.XXXXXX)
 NOBUILDID=0000000000000000000000000000000000000000
 
@@ -22,13 +32,13 @@ MANIFEST=$(mktemp /tmp/perf-archive-manifest.XXXXXX)
 
 cut -d ' ' -f 1 $BUILDIDS | \
 while read build_id ; do
-        linkname=$DEBUGDIR.build-id/${build_id:0:2}/${build_id:2}
+        linkname=$PERF_BUILDID_DIR.build-id/${build_id:0:2}/${build_id:2}
         filename=$(readlink -f $linkname)
-        echo ${linkname#$DEBUGDIR} >> $MANIFEST
-        echo ${filename#$DEBUGDIR} >> $MANIFEST
+        echo ${linkname#$PERF_BUILDID_DIR} >> $MANIFEST
+        echo ${filename#$PERF_BUILDID_DIR} >> $MANIFEST
 done
 
-tar cfj $PERF_DATA.tar.bz2 -C $DEBUGDIR -T $MANIFEST
+tar cfj $PERF_DATA.tar.bz2 -C $PERF_BUILDID_DIR -T $MANIFEST
 rm -f $MANIFEST $BUILDIDS
 echo -e "Now please run:\n"
 echo -e "$ tar xvf $PERF_DATA.tar.bz2 -C ~/.debug\n"