kernel/tools/perf/util/llvm-utils.h, branch linux-4.3.y

perf tests: Add LLVM test for eBPF on-the-fly compiling

2015-08-07T13:57:24Z

Previous patches introduce llvm__compile_bpf() to compile source file to eBPF object. This patch adds testcase to test it. It also tests libbpf by opening generated object after applying next patch which introduces HAVE_LIBBPF_SUPPORT option. Since llvm__compile_bpf() prints long messages which users who don't explicitly test llvm doesn't care, this patch set verbose to -1 to suppress all debug, warning and error message, and hint user use 'perf test -v' to see the full output. For the same reason, if clang is not found in PATH and there's no [llvm] section in .perfconfig, skip this test. Signed-off-by: Wang Nan Acked-by: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/n/1436445342-1402-17-git-send-email-wangnan0@huawei.com [ Add tools/lib/bpf/ to tools/perf/MANIFEST, so that the tarball targets build ] Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Call clang to compile C source to object code

2015-08-07T13:16:59Z

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 b236512280fb: 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 Acked-by: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li 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

perf tools: Introduce llvm config options

2015-08-07T13:16:59Z

This patch introduces [llvm] config section with 5 options. Following patches will use then to config llvm dynamica compiling. 'llvm-utils.[ch]' is introduced in this patch for holding all llvm/clang related stuffs. Example: [llvm] # Path to clang. If omit, search it from $PATH. clang-path = "/path/to/clang" # Cmdline template. Following line shows its default value. # Environment variable is used to passing options. # # *NOTE*: -D__KERNEL__ MUST appears before $CLANG_OPTIONS, # so user have a chance to use -U__KERNEL__ in $CLANG_OPTIONS # to cancel it. clang-bpf-cmd-template = "$CLANG_EXEC -D__KERNEL__ $CLANG_OPTIONS \ $KERNEL_INC_OPTIONS -Wno-unused-value \ -Wno-pointer-sign -working-directory \ $WORKING_DIR -c $CLANG_SOURCE -target \ bpf -O2 -o -" # Options passed to clang, will be passed to cmdline by # $CLANG_OPTIONS. clang-opt = "-Wno-unused-value -Wno-pointer-sign" # kbuild directory. If not set, use /lib/modules/`uname -r`/build. # If set to "" deliberately, skip kernel header auto-detector. kbuild-dir = "/path/to/kernel/build" # Options passed to 'make' when detecting kernel header options. kbuild-opts = "ARCH=x86_64" Signed-off-by: Wang Nan Acked-by: Alexei Starovoitov Cc: Brendan Gregg Cc: Daniel Borkmann Cc: David Ahern Cc: He Kuang Cc: Jiri Olsa Cc: Kaixu Xia Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1437477214-149684-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo