perf tools: Support --prefix/--prefix-strip

The objdump utility has useful --prefix / --prefix-strip options to
allow changing source code file names hardcoded into executables' debug
info. Add options to 'perf report', 'perf top' and 'perf annotate',
which are then passed to objdump.

  $ mkdir foo
  $ echo 'main() { for (;;); }' > foo/foo.c
  $ gcc -g foo/foo.c
  foo/foo.c:1:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
      1 | main() { for (;;); }
        | ^~~~
  $ perf record ./a.out
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.230 MB perf.data (5721 samples) ]
  $ mv foo bar
  $ perf annotate
  <does not show source code>
  $ perf annotate --prefix=/home/ak/lsrc/git/bar --prefix-strip=5
  <does show source code>

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
LPU-Reference: 20200107210444.214071-1-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/tools/perf/Documentation/perf-report.txt b/tools/perf/Documentation/perf-report.txt
index 8dbe2119686a..db61f16ffa56 100644
--- a/tools/perf/Documentation/perf-report.txt
+++ b/tools/perf/Documentation/perf-report.txt
@@ -367,6 +367,12 @@ OPTIONS
 --objdump=<path>::
         Path to objdump binary.
 
+--prefix=PREFIX::
+--prefix-strip=N::
+	Remove first N entries from source file path names in executables
+	and add PREFIX. This allows to display source code compiled on systems
+	with different file system layout.
+
 --group::
 	Show event group information together. It forces group output also
 	if there are no groups defined in data file.