This is the core patch for supporting eBPF on-the-fly compiling, does
the following work:
1. Search clang compiler using search_program().
2. Run command template defined in llvm-bpf-cmd-template option in
[llvm] config section using read_from_pipe(). Patch of clang and
source code path is injected into shell command using environment
variable using force_set_env().
Commiter notice:
When building with DEBUG=1 we get a compiler error that gets fixed with
the same approach described in commit b236512280:
perf kmem: Fix compiler warning about may be accessing uninitialized variable
The last argument to strtok_r doesn't need to be initialized, its
just a placeholder to make this routine reentrant, but gcc doesn't know
about that and complains, breaking the build, fix it by setting it to
NULL.
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Ahern <dsahern@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/n/1436445342-1402-14-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4cea3a9cb3