From a7bac9930ec43fc3b6746d7a468c9d72d1dfcf7b Mon Sep 17 00:00:00 2001
From: Matthias Reichl <hias@horus.com>
Date: Mon, 5 Feb 2018 15:38:18 +0100
Subject: [PATCH] linux: install perf in development builds

perf will be built if CONFIG_PERF_EVENTS is enabled in the
kernel config.

elfutils, binutils and libunwind are needed to get symbols
of userspace programs in perf output.

zlib is an implicit dependency of elfutils and and optional
one for perf - but better add it here.

openssl/libcrypto is an optional dependency for perf, add it
so that the perf configuration on clean build is identical
to an unclean rebuild.

Signed-off-by: Matthias Reichl <hias@horus.com>
---
 packages/linux/package.mk | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/packages/linux/package.mk b/packages/linux/package.mk
index e621e1d3e4..f8fb1763eb 100644
--- a/packages/linux/package.mk
+++ b/packages/linux/package.mk
@@ -50,6 +50,11 @@ else
   PKG_KERNEL_CFG_FILE=$PKG_DIR/config/$PKG_CFG_FILE
 fi
 
+if [ "$DEVTOOLS" = "yes" ] && grep -q ^CONFIG_PERF_EVENTS= $PKG_KERNEL_CFG_FILE ; then
+  PKG_BUILD_PERF="yes"
+  PKG_DEPENDS_TARGET="$PKG_DEPENDS_TARGET binutils elfutils libunwind zlib openssl"
+fi
+
 case "$LINUX" in
   amlogic-3.10)
     PKG_VERSION="02fdb27"
@@ -175,6 +180,25 @@ make_target() {
   rm -f $INSTALL/$(get_kernel_overlay_dir)/lib/modules/*/build
   rm -f $INSTALL/$(get_kernel_overlay_dir)/lib/modules/*/source
 
+  if [ "$PKG_BUILD_PERF" = "yes" ] ; then
+    ( cd tools/perf
+      WERROR=0 \
+      NO_LIBPERL=1 \
+      NO_LIBPYTHON=1 \
+      NO_SLANG=1 \
+      NO_GTK2=1 \
+      NO_LIBNUMA=1 \
+      NO_LIBAUDIT=1 \
+      NO_LZMA=1 \
+      NO_SDT=1 \
+      LDFLAGS="-ldw -ldwfl -lebl -lelf -ldl -lz" \
+      EXTRA_PERFLIBS="-lebl" \
+        make
+      mkdir -p $INSTALL/usr/bin
+        cp perf $INSTALL/usr/bin
+    )
+  fi
+
   ( cd $ROOT
     rm -rf $BUILD/initramfs
     $SCRIPTS/install initramfs