[PATCH 1/3] perf tools: Allow to build with -ltcmalloc

[Jiri Olsa]

By using "make TCMALLOC=1" you can enable perf to be build
for usage with libtcmalloc.so (gperftools).

Get heap profile (tools/perf directory):

  $ <install gperftools>
  $ make TCMALLOC=1 DEBUG=1
  $ HEAPPROFILE=/tmp/heapprof ./perf ...
  $ pprof ./perf /tmp/heapprof.000*
  (pprof) top
  Total: 2335.5 MB
    1735.1  74.3%  74.3%   1735.1  74.3% memdup
     402.0  17.2%  91.5%    402.0  17.2% zalloc
     140.2   6.0%  97.5%    145.8   6.2% map__new
      33.6   1.4%  98.9%     33.6   1.4% symbol__new
      12.4   0.5%  99.5%     12.4   0.5% alloc_event
       6.2   0.3%  99.7%      6.2   0.3% nsinfo__new
       5.5   0.2% 100.0%      5.5   0.2% nsinfo__copy
       0.3   0.0% 100.0%      0.3   0.0% dso__new
       0.1   0.0% 100.0%      0.1   0.0% do_read_string
       0.0   0.0% 100.0%      0.0   0.0% __GI__IO_file_doallocate

See callstack:
  $ pprof --pdf ./perf /tmp/heapprof.00* > callstack.pdf
  $ pprof --web ./perf /tmp/heapprof.00*

Link: http://lkml.kernel.org/n/tip-qyo3c7z69dysk10sr3pf5k05@xxxxxxxxxxxxxx
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
 tools/perf/Makefile.config | 5 +++++
 tools/perf/Makefile.perf   | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 063202c53b64..1783427da9b0 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -265,6 +265,11 @@ LDFLAGS += -Wl,-z,noexecstack
 
 EXTLIBS = -lpthread -lrt -lm -ldl
 
+ifneq ($(TCMALLOC),)
+  CFLAGS += -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-free
+  EXTLIBS += -ltcmalloc
+endif
+
 ifeq ($(FEATURES_DUMP),)
 include $(srctree)/tools/build/Makefile.feature
 else
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index a099a8a89447..8f1ba986d3bf 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -114,6 +114,8 @@ include ../scripts/utilities.mak
 # Define NO_LIBZSTD if you do not want support of Zstandard based runtime
 # trace compression in record mode.
 #
+# Define TCMALLOC to enable tcmalloc heap profiling.
+#
 
 # As per kernel Makefile, avoid funny character set dependencies
 unexport LC_ALL
-- 
2.21.0