linux-toradex.git/tools/perf/util/c++, branch v4.10

perf clang: Compile BPF script using builtin clang support

2016-12-05T18:51:45+00:00

After this patch, perf utilizes builtin clang support to build BPF
script, no longer depend on external clang, but fallbacking to it
if for some reason the builtin compiling framework fails.

Test:

  $ type clang
  -bash: type: clang: not found
  $ cat ~/.perfconfig
  $ echo '#define LINUX_VERSION_CODE 0x040700' > ./test.c
  $ cat ./tools/perf/tests/bpf-script-example.c >> ./test.c
  $ ./perf record -v --dry-run -e ./test.c 2>&1 | grep builtin
  bpf: successfull builtin compilation
  $

Can't pass cflags so unable to include kernel headers now. Will be fixed
by following commits.

Committer notes:

Make sure '-v' comes before the '-e ./test.c' in the command line otherwise the
'verbose' variable will not be set when the bpf event is parsed and thus the
pr_debug indicating a 'successfull builtin compilation' will not be output, as
the debug level (1) will be less than what 'verbose' has at that point (0).

Signed-off-by: Wang Nan 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-16-wangnan0@huawei.com
[ Spell check/reflow successfull pr_debug string ]
Signed-off-by: Arnaldo Carvalho de Melo

perf clang: Support compile IR to BPF object and add testcase

2016-12-05T18:51:44+00:00

getBPFObjectFromModule() is introduced to compile LLVM IR(Module)
to BPF object. Add new testcase for it.

Test result:
  $ ./buildperf/perf test -v clang
  51: builtin clang support                               :
  51.1: builtin clang compile C source to IR              :
  --- start ---
  test child forked, pid 21822
  test child finished with 0
  ---- end ----
  builtin clang support subtest 0: Ok
  51.2: builtin clang compile C source to ELF object      :
  --- start ---
  test child forked, pid 21823
  test child finished with 0
  ---- end ----
  builtin clang support subtest 1: Ok

Signed-off-by: Wang Nan 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-15-wangnan0@huawei.com
[ Remove redundant "Test" from entry descriptions ]
Signed-off-by: Arnaldo Carvalho de Melo

perf clang: Update test case to use real BPF script

2016-12-05T18:51:44+00:00

Allow C++ code to use util.h and tests/llvm.h. Let 'perf test' compile a
real BPF script.

Signed-off-by: Wang Nan 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-14-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf clang: Allow passing CFLAGS to builtin clang

2016-12-05T18:51:44+00:00

Improve getModuleFromSource() API to accept a cflags list. This feature
will be used to pass LINUX_VERSION_CODE and -I flags.

Signed-off-by: Wang Nan 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-13-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf clang: Use real file system for #include

2016-12-05T18:51:44+00:00

Utilize clang's OverlayFileSystem facility, allow CompilerInstance to
access real file system.

With this patch the '#include' directive can be used.

Add a new getModuleFromSource for real file.

Signed-off-by: Wang Nan 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-12-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

perf clang: Add builtin clang support ant test case

2016-12-05T18:51:43+00:00

Add basic clang support in clang.cpp and test__clang() testcase. The
first testcase checks if builtin clang is able to generate LLVM IR.

tests/clang.c is a proxy. Real testcase resides in
utils/c++/clang-test.cpp in c++ and exports C interface to perf test
subsystem.

Test result:

   $ perf test -v clang
   51: builtin clang support                               :
   51.1: Test builtin clang compile C source to IR              :
   --- start ---
   test child forked, pid 13215
   test child finished with 0
   ---- end ----
   Test builtin clang support subtest 0: Ok

Committer note:

Make sure you've enabled CLANG and LLVM builtin support by setting
the LIBCLANGLLVM variable on the make command line, e.g.:

  make LIBCLANGLLVM=1 O=/tmp/build/perf -C tools/perf install-bin

Otherwise you'll get this when trying to do the 'perf test' call above:

  # perf test clang
  51: builtin clang support                      : Skip (not compiled in)
  #

Signed-off-by: Wang Nan 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexei Starovoitov 
Cc: He Kuang 
Cc: Jiri Olsa 
Cc: Joe Stringer 
Cc: Zefan Li 
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/20161126070354.141764-11-wangnan0@huawei.com
[ Removed "Test" from descriptions, redundant and already removed from all the other entries ]
Signed-off-by: Arnaldo Carvalho de Melo