wireguard-linux/tools/bpf/bpftool/Makefile, branch jd/unified-crypt-queue

tools/bpf: Move linux/types.h for selftests and bpftool

2020-03-13T19:56:34Z

Commit fe4eb069edb7 ("bpftool: Use linux/types.h from source tree for profiler build") added a build dependency on tools/testing/selftests/bpf to tools/bpf/bpftool. This is suboptimal with respect to a possible stand-alone build of bpftool. Fix this by moving tools/testing/selftests/bpf/include/uapi/linux/types.h to tools/include/uapi/linux/types.h. This requires an adjustment in the include search path order for the tests in tools/testing/selftests/bpf so that tools/include/linux/types.h is selected when building host binaries and tools/include/uapi/linux/types.h is selected when building bpf binaries. Verified by compiling bpftool and the bpf selftests on x86_64 with this change. Fixes: fe4eb069edb7 ("bpftool: Use linux/types.h from source tree for profiler build") Suggested-by: Andrii Nakryiko Signed-off-by: Tobias Klauser Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200313113105.6918-1-tklauser@distanz.ch

bpftool: Skeleton should depend on libbpf

2020-03-12T23:08:33Z

Add the dependency to libbpf, to fix build errors like: In file included from skeleton/profiler.bpf.c:5: .../bpf_helpers.h:5:10: fatal error: 'bpf_helper_defs.h' file not found #include "bpf_helper_defs.h" ^~~~~~~~~~~~~~~~~~~ 1 error generated. make: *** [skeleton/profiler.bpf.o] Error 1 make: *** Waiting for unfinished jobs.... Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command") Suggested-by: Quentin Monnet Signed-off-by: Song Liu Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/20200312182332.3953408-3-songliubraving@fb.com

bpftool: Only build bpftool-prog-profile if supported by clang

2020-03-12T23:08:33Z

bpftool-prog-profile requires clang to generate BTF for global variables. When compared with older clang, skip this command. This is achieved by adding a new feature, clang-bpf-global-var, to tools/build/feature. Signed-off-by: Song Liu Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200312182332.3953408-2-songliubraving@fb.com

bpftool: Use linux/types.h from source tree for profiler build

2020-03-12T15:22:41Z

When compiling bpftool on a system where the /usr/include/asm symlink doesn't exist (e.g. on an Ubuntu system without gcc-multilib installed), the build fails with: CLANG skeleton/profiler.bpf.o In file included from skeleton/profiler.bpf.c:4: In file included from /usr/include/linux/bpf.h:11: /usr/include/linux/types.h:5:10: fatal error: 'asm/types.h' file not found #include ^~~~~~~~~~~~~ 1 error generated. make: *** [Makefile:123: skeleton/profiler.bpf.o] Error 1 This indicates that the build is using linux/types.h from system headers instead of source tree headers. To fix this, adjust the clang search path to include the necessary headers from tools/testing/selftests/bpf/include/uapi and tools/include/uapi. Also use __bitwise__ instead of __bitwise in skeleton/profiler.h to avoid clashing with the definition in tools/testing/selftests/bpf/include/uapi/linux/types.h. Signed-off-by: Tobias Klauser Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200312130330.32239-1-tklauser@distanz.ch

bpftool: Introduce "prog profile" command

2020-03-09T23:04:07Z

With fentry/fexit programs, it is possible to profile BPF program with hardware counters. Introduce bpftool "prog profile", which measures key metrics of a BPF program. bpftool prog profile command creates per-cpu perf events. Then it attaches fentry/fexit programs to the target BPF program. The fentry program saves perf event value to a map. The fexit program reads the perf event again, and calculates the difference, which is the instructions/cycles used by the target program. Example input and output: ./bpftool prog profile id 337 duration 3 cycles instructions llc_misses 4228 run_cnt 3403698 cycles (84.08%) 3525294 instructions # 1.04 insn per cycle (84.05%) 13 llc_misses # 3.69 LLC misses per million isns (83.50%) This command measures cycles and instructions for BPF program with id 337 for 3 seconds. The program has triggered 4228 times. The rest of the output is similar to perf-stat. In this example, the counters were only counting ~84% of the time because of time multiplexing of perf counters. Note that, this approach measures cycles and instructions in very small increments. So the fentry/fexit programs introduce noticeable errors to the measurement results. The fentry/fexit programs are generated with BPF skeletons. Therefore, we build bpftool twice. The first time _bpftool is built without skeletons. Then, _bpftool is used to generate the skeletons. The second time, bpftool is built with skeletons. Signed-off-by: Song Liu Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20200309173218.2739965-2-songliubraving@fb.com

bpftool: Use consistent include paths for libbpf

2020-01-21T00:37:45Z

Fix bpftool to include libbpf header files with the bpf/ prefix, to be consistent with external users of the library. Also ensure that all includes of exported libbpf header files (those that are exported on 'make install' of the library) use bracketed includes instead of quoted. To make sure no new files are introduced that doesn't include the bpf/ prefix in its include, remove tools/lib/bpf from the include path entirely, and use tools/lib instead. Fixes: 6910d7d3867a ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157952560684.1683545.4765181397974997027.stgit@toke.dk

tools: bpftool: do not link twice against libbpf.a in Makefile

2019-08-30T22:38:16Z

In bpftool's Makefile, $(LIBS) includes $(LIBBPF), therefore the library is used twice in the linking command. No need to have $(LIBBPF) (from $^) on that command, let's do with "$(OBJS) $(LIBS)" (but move $(LIBBPF) _before_ the -l flags in $(LIBS)). Signed-off-by: Ilya Leoshkevich Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann

tools: bpf: account for generated feature/ and libbpf/ directories

2019-08-30T22:38:16Z

When building "tools/bpf" from the top of the Linux repository, the build system passes a value for the $(OUTPUT) Makefile variable to tools/bpf/Makefile and tools/bpf/bpftool/Makefile, which results in generating "libbpf/" (for bpftool) and "feature/" (bpf and bpftool) directories inside the tree. This commit adds such directories to the relevant .gitignore files, and edits the Makefiles to ensure they are removed on "make clean". The use of "rm" is also made consistent throughout those Makefiles (relies on the $(RM) variable, use "--" to prevent interpreting $(OUTPUT)/$(DESTDIR) as options. v2: - New patch. Signed-off-by: Quentin Monnet Signed-off-by: Daniel Borkmann

tools: bpftool: improve and check builds for different make invocations

2019-08-30T22:38:16Z

There are a number of alternative "make" invocations that can be used to compile bpftool. The following invocations are expected to work: - through the kbuild system, from the top of the repository (make tools/bpf) - by telling make to change to the bpftool directory (make -C tools/bpf/bpftool) - by building the BPF tools from tools/ (cd tools && make bpf) - by running make from bpftool directory (cd tools/bpf/bpftool && make) Additionally, setting the O or OUTPUT variables should tell the build system to use a custom output path, for each of these alternatives. The following patch fixes the following invocations: $ make tools/bpf $ make tools/bpf O= $ make -C tools/bpf/bpftool OUTPUT= $ make -C tools/bpf/bpftool O= $ cd tools/ && make bpf O= $ cd tools/bpf/bpftool && make OUTPUT= $ cd tools/bpf/bpftool && make O= After this commit, the build still fails for two variants when passing the OUTPUT variable: $ make tools/bpf OUTPUT= $ cd tools/ && make bpf OUTPUT= In order to remember and check what make invocations are supposed to work, and to document the ones which do not, a new script is added to the BPF selftests. Note that some invocations require the kernel to be configured, so the script skips them if no .config file is found. v2: - In make_and_clean(), set $ERROR to 1 when "make" returns non-zero, even if the binary was produced. - Run "make clean" from the correct directory (bpf/ instead of bpftool/, when relevant). Reported-by: Lorenz Bauer Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann

tools: bpftool: ignore make built-in rules for getting kernel version

2019-08-30T22:38:16Z

Bpftool calls the toplevel Makefile to get the kernel version for the sources it is built from. But when the utility is built from the top of the kernel repository, it may dump the following error message for certain architectures (including x86): $ make tools/bpf [...] make[3]: *** [checkbin] Error 1 [...] This does not prevent bpftool compilation, but may feel disconcerting. The "checkbin" arch-dependent target is not supposed to be called for target "kernelversion", which is a simple "echo" of the version number. It turns out this is caused by the make invocation in tools/bpf/bpftool, which attempts to find implicit rules to apply. Extract from debug output: Reading makefiles... Reading makefile 'Makefile'... Reading makefile 'scripts/Kbuild.include' (search path) (no ~ expansion)... Reading makefile 'scripts/subarch.include' (search path) (no ~ expansion)... Reading makefile 'arch/x86/Makefile' (search path) (no ~ expansion)... Reading makefile 'scripts/Makefile.kcov' (search path) (no ~ expansion)... Reading makefile 'scripts/Makefile.gcc-plugins' (search path) (no ~ expansion)... Reading makefile 'scripts/Makefile.kasan' (search path) (no ~ expansion)... Reading makefile 'scripts/Makefile.extrawarn' (search path) (no ~ expansion)... Reading makefile 'scripts/Makefile.ubsan' (search path) (no ~ expansion)... Updating makefiles.... Considering target file 'scripts/Makefile.ubsan'. Looking for an implicit rule for 'scripts/Makefile.ubsan'. Trying pattern rule with stem 'Makefile.ubsan'. [...] Trying pattern rule with stem 'Makefile.ubsan'. Trying implicit prerequisite 'scripts/Makefile.ubsan.o'. Looking for a rule with intermediate file 'scripts/Makefile.ubsan.o'. Avoiding implicit rule recursion. Trying pattern rule with stem 'Makefile.ubsan'. Trying rule prerequisite 'prepare'. Trying rule prerequisite 'FORCE'. Found an implicit rule for 'scripts/Makefile.ubsan'. Considering target file 'prepare'. File 'prepare' does not exist. Considering target file 'prepare0'. File 'prepare0' does not exist. Considering target file 'archprepare'. File 'archprepare' does not exist. Considering target file 'archheaders'. File 'archheaders' does not exist. Finished prerequisites of target file 'archheaders'. Must remake target 'archheaders'. Putting child 0x55976f4f6980 (archheaders) PID 31743 on the chain. To avoid that, pass the -r and -R flags to eliminate the use of make built-in rules (and while at it, built-in variables) when running command "make kernelversion" from bpftool's Makefile. Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann