[tip:perf/urgent] perf tools: Make check-headers.sh check based on kernel dir

[tip-bot for Jiri Olsa]

Commit-ID:  7ea6e983b2cce9a4277ea602c2976d18bd75a908
Gitweb:     https://git.kernel.org/tip/7ea6e983b2cce9a4277ea602c2976d18bd75a908
Author:     Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Mon, 13 Aug 2018 13:15:03 +0200
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 14 Aug 2018 15:08:33 -0300

perf tools: Make check-headers.sh check based on kernel dir

Changing the logic to compare files with paths relative to kernel source
base dir. This way we can keep the output message for 2 unrelated files,
which is coming in following patch.

Committer testing:

Remove a line from tools/arch/x86/lib/memcpy_64.S to have it detected:

make: Entering directory '/home/acme/git/perf/tools/perf'
  BUILD:   Doing 'make -j4' parallel build
Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
  INSTALL  GTK UI
  INSTALL  binaries

Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Alexander Kapshuk <alexander.kapshuk@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20180813111504.3568-1-jolsa@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20180814072726.GA13931@krava
[ Do not use pushd/popd, its a bashism, reported by Michael Ellerman, fixed by Jiri Olsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/check-headers.sh | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/tools/perf/check-headers.sh b/tools/perf/check-headers.sh
index ea48aa6f8d19..b61f8a4dfca3 100755
--- a/tools/perf/check-headers.sh
+++ b/tools/perf/check-headers.sh
@@ -69,8 +69,8 @@ check_2 () {
 
   test -f $file2 && {
     eval $cmd || {
-      echo "Warning: Kernel ABI header at 'tools/$file' differs from latest version at '$file'" >&2
-      echo diff -u tools/$file $file
+      echo "Warning: Kernel ABI header at '$file1' differs from latest version at '$file2'" >&2
+      echo diff -u $file1 $file2
     }
   }
 }
@@ -80,7 +80,7 @@ check () {
 
   shift
 
-  check_2 ../$file ../../$file $*
+  check_2 tools/$file $file $*
 }
 
 # Check if we have the kernel headers (tools/perf/../../include), else
@@ -88,6 +88,8 @@ check () {
 # differences.
 test -d ../../include || exit 0
 
+cd ../..
+
 # simple diff check
 for i in $HEADERS; do
   check $i -B
@@ -98,3 +100,5 @@ check arch/x86/lib/memcpy_64.S        '-I "^EXPORT_SYMBOL" -I "^#include <asm/ex
 check arch/x86/lib/memset_64.S        '-I "^EXPORT_SYMBOL" -I "^#include <asm/export.h>"'
 check include/uapi/asm-generic/mman.h '-I "^#include <\(uapi/\)*asm-generic/mman-common.h>"'
 check include/uapi/linux/mman.h       '-I "^#include <\(uapi/\)*asm/mman.h>"'
+
+cd tools/perf