kernel/linux.git/tools/perf/Makefile.config, branch v6.12.80

perf build: Warn when libdebuginfod devel files are not available

2025-06-19T13:32:04+00:00

[ Upstream commit 4fce4b91fd1aabb326c46e237eb4b19ab72598f8 ] While working on 'perf version --build-options' I noticed that: $ perf version --build-options perf version 6.15.rc1.g312a07a00d31 aio: [ on ] # HAVE_AIO_SUPPORT bpf: [ on ] # HAVE_LIBBPF_SUPPORT bpf_skeletons: [ on ] # HAVE_BPF_SKEL debuginfod: [ OFF ] # HAVE_DEBUGINFOD_SUPPORT And looking at tools/perf/Makefile.config I also noticed that it is not opt-in, meaning we will attempt to build with it in all normal cases. So add the usual warning at build time to let the user know that something recommended is missing, now we see: Makefile.config:563: No elfutils/debuginfod.h found, no debuginfo server support, please install elfutils-debuginfod-client-devel or equivalent And after following the recommendation: $ perf check feature debuginfod debuginfod: [ on ] # HAVE_DEBUGINFOD_SUPPORT $ ldd ~/bin/perf | grep debuginfo libdebuginfod.so.1 => /lib64/libdebuginfod.so.1 (0x00007fee5cf5f000) $ With this feature on several perf tools will fetch what is needed and not require all the contents of the debuginfo packages, for instance: # rpm -qa | grep kernel-debuginfo # pahole --running_kernel_vmlinux pahole: couldn't find a vmlinux that matches the running kernel HINT: Maybe you're inside a container or missing a debuginfo package? # # perf trace -e open* perf probe --vars icmp_rcv 0.000 ( 0.005 ms): perf/97391 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) = 3 0.014 ( 0.004 ms): perf/97391 openat(dfd: CWD, filename: "/lib64/libm.so.6", flags: RDONLY|CLOEXEC) = 3 32130.100 ( 0.008 ms): perf/97391 openat(dfd: CWD, filename: "/root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo") = 3 Available variables at icmp_rcv @ struct sk_buff* skb # # pahole --running_kernel_vmlinux /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo # file /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, BuildID[sha1]=aa3c82b4a13f9c0e0301bebb20fe958c4db6f362, with debug_info, not stripped # ls -la /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo -r--------. 1 root root 475401512 Mar 27 21:00 /root/.cache/debuginfod_client/aa3c82b4a13f9c0e0301bebb20fe958c4db6f362/debuginfo # Then, cached: # perf stat --null perf probe --vars icmp_rcv Available variables at icmp_rcv @ struct sk_buff* skb Performance counter stats for 'perf probe --vars icmp_rcv': 0.671389041 seconds time elapsed 0.519176000 seconds user 0.150860000 seconds sys Fixes: c7a14fdcb3fa7736 ("perf build-ids: Fall back to debuginfod query if debuginfo not found") Tested-by: Ingo Molnar Cc: Adrian Hunter Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ian Rogers Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Frank Ch. Eigler Link: https://lore.kernel.org/r/Z_dkNDj9EPFwPqq1@gmail.com [ Folded patch from Ingo to have the debian/ubuntu devel package added build warning message ] Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf: Always feature test reallocarray

2025-04-10T12:39:22+00:00

[ Upstream commit 4c4c0724d6521a8092b7c16f8f210c5869d95b17 ] This is also used in util/comm.c now, so instead of selectively doing the feature test, always do it. If it's ever used anywhere else it's less likely to cause another build failure. This doesn't remove the need to manually include libc_compat.h, and missing that will still cause an error for glibc < 2.26. There isn't a way to fix that without poisoning reallocarray like libbpf did, but that has other downsides like making memory debugging tools less useful. So for Perf keep it like this and we'll have to fix up any missed includes. Fixes the following build error: util/comm.c:152:31: error: implicit declaration of function 'reallocarray' [-Wimplicit-function-declaration] 152 | tmp = reallocarray(comm_strs->strs, | ^~~~~~~~~~~~ Fixes: 13ca628716c6 ("perf comm: Add reference count checking to 'struct comm_str'") Reported-by: Ali Utku Selen Signed-off-by: James Clark Reviewed-by: Ian Rogers Link: https://lore.kernel.org/r/20250129154405.777533-1-james.clark@linaro.org Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf build: Add missing cflags when building with custom libtraceevent

2024-12-05T13:02:23+00:00

[ Upstream commit d5a0a4ab4af4c27de097b78d6f1b7e7f7e31908f ] When building with custom libtraceevent, below errors occur: $ make -C tools/perf NO_LIBPYTHON=1 PKG_CONFIG_PATH= In file included from util/session.h:5, from builtin-buildid-list.c:17: util/trace-event.h:153:10: fatal error: traceevent/event-parse.h: No such file or directory 153 | #include | ^~~~~~~~~~~~~~~~~~~~~~~~~~ This is because the include path is missed in the cflags. Add it. Fixes: 0f0e1f445690 ("perf build: Use pkg-config for feature check for libtrace{event,fs}") Signed-off-by: Yicong Yang Reviewed-by: Leo Yan Reviewed-by: Guilherme Amadio Cc: linuxarm@huawei.com Link: https://lore.kernel.org/r/20241024133236.31016-1-yangyicong@huawei.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf build: Change the clang check back to 12.0.1

2024-10-23T14:34:56+00:00

This serves as a revert for this patch: https://lore.kernel.org/linux-perf-users/ZuGL9ROeTV2uXoSp@x1/ Signed-off-by: Howard Chu Tested-by: James Clark Cc: Adrian Hunter Cc: Alan Maguire Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20241011021403.4089793-2-howardchu95@gmail.com Signed-off-by: Arnaldo Carvalho de Melo

perf build: Fix build feature-dwarf_getlocations fail for old libdw

2024-10-02T21:21:49+00:00

For libdw versions below 0.177, need to link libdl.a in addition to libbebl.a during static compilation, otherwise feature-dwarf_getlocations compilation will fail. Before: $ make LDFLAGS=-static BUILD: Doing 'make -j20' parallel build Makefile.config:483: Old libdw.h, finding variables at given 'perf probe' point will not work, install elfutils-devel/libdw-dev >= 0.157 $ cat ../build/feature/test-dwarf_getlocations.make.output /usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/libebl.a(eblclosebackend.o): in function `ebl_closebackend': (.text+0x20): undefined reference to `dlclose' collect2: error: ld returned 1 exit status After: $ make LDFLAGS=-static Auto-detecting system features: ... dwarf: [ on ] $ ./perf probe Usage: perf probe [] 'PROBEDEF' ['PROBEDEF' ...] or: perf probe [] --add 'PROBEDEF' [--add 'PROBEDEF' ...] or: perf probe [] --del '[GROUP:]EVENT' ... or: perf probe --list [GROUP:]EVENT ... Fixes: 536661da6ea18fe6 ("perf: build: Only link libebl.a for old libdw") Reviewed-by: Leo Yan Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240919013513.118527-3-yangjihong@bytedance.com Signed-off-by: Arnaldo Carvalho de Melo

perf build: Fix static compilation error when libdw is not installed

2024-10-02T21:21:49+00:00

If libdw is not installed in build environment, the output of 'pkg-config --modversion libdw' is empty, causing LIBDW_VERSION_2 to be empty and the shell test will have the following error: /bin/sh: 1: test: -lt: unexpected operator Before: $ pkg-config --modversion libdw Package libdw was not found in the pkg-config search path. Perhaps you should add the directory containing `libdw.pc' to the PKG_CONFIG_PATH environment variable No package 'libdw' found $ make LDFLAGS=-static -j16 BUILD: Doing 'make -j20' parallel build Package libdw was not found in the pkg-config search path. Perhaps you should add the directory containing `libdw.pc' to the PKG_CONFIG_PATH environment variable No package 'libdw' found /bin/sh: 1: test: -lt: unexpected operator After: 1. libdw is not installed: $ pkg-config --modversion libdw Package libdw was not found in the pkg-config search path. Perhaps you should add the directory containing `libdw.pc' to the PKG_CONFIG_PATH environment variable No package 'libdw' found $ make LDFLAGS=-static -j16 BUILD: Doing 'make -j20' parallel build Package libdw was not found in the pkg-config search path. Perhaps you should add the directory containing `libdw.pc' to the PKG_CONFIG_PATH environment variable No package 'libdw' found Makefile.config:473: No libdw DWARF unwind found, Please install elfutils-devel/libdw-dev >= 0.158 and/or set LIBDW_DIR 2. libdw version is lower than 0.177 $ pkg-config --modversion libdw 0.176 $ make LDFLAGS=-static -j16 BUILD: Doing 'make -j20' parallel build Auto-detecting system features: ... dwarf: [ on ] INSTALL libsubcmd_headers INSTALL libapi_headers INSTALL libperf_headers INSTALL libsymbol_headers INSTALL libbpf_headers LINK perf 3. libdw version is higher than 0.177 $ pkg-config --modversion libdw 0.186 $ make LDFLAGS=-static -j16 BUILD: Doing 'make -j20' parallel build Auto-detecting system features: ... dwarf: [ on ] CC util/bpf-utils.o CC util/pfm.o LD util/perf-util-in.o LD perf-util-in.o AR libperf-util.a LINK perf Fixes: 536661da6ea18fe6 ("perf: build: Only link libebl.a for old libdw") Reviewed-by: Leo Yan Signed-off-by: Yang Jihong Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240919013513.118527-2-yangjihong@bytedance.com Signed-off-by: Arnaldo Carvalho de Melo

tools: Drop nonsensical -O6

2024-09-11T16:08:36+00:00

-O6 is very much not-a-thing. Really, this should've been dropped entirely in 49b3cd306e60b9d8 ("tools: Set the maximum optimization level according to the compiler being used") instead of just passing it for not-Clang. Just collapse it down to -O3, instead of "-O6 unless Clang, in which case -O3". GCC interprets > -O3 as -O3. It doesn't even interpret > -O3 as -Ofast, which is a good thing, given -Ofast has specific (non-)requirements for code built using it. So, this does nothing except look a bit daft. Remove the silliness and also save a few lines in the Makefiles accordingly. Reviewed-by: Ian Rogers Reviewed-by: Jesper Juhl Signed-off-by: Sam James Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Bill Wendling Cc: Ingo Molnar Cc: Jiri Olsa Cc: Justin Stitt Cc: Kan Liang Cc: Mark Rutland Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: llvm@lists.linux.dev Link: https://lore.kernel.org/r/4f01524fa4ea91c7146a41e26ceaf9dae4c127e4.1725821201.git.sam@gentoo.org Signed-off-by: Arnaldo Carvalho de Melo

perf build: Require at least clang 16.0.6 to build BPF skeletons

2024-09-11T12:35:34+00:00

Howard reported problems using perf features that use BPF: perf $ clang -v Debian clang version 15.0.6 Target: x86_64-pc-linux-gnu Thread model: posix InstalledDir: /bin Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12 Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12 Candidate multilib: .;@m64 Selected multilib: .;@m64 perf $ ./perf trace -e write --max-events=1 libbpf: prog 'sys_enter_rename': BPF program load failed: Permission denied libbpf: prog 'sys_enter_rename': -- BEGIN PROG LOAD LOG -- 0: R1=ctx() R10=fp0 But it works with: perf $ clang -v Debian clang version 16.0.6 (15~deb12u1) Target: x86_64-pc-linux-gnu Thread model: posix InstalledDir: /bin Found candidate GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12 Selected GCC installation: /bin/../lib/gcc/x86_64-linux-gnu/12 Candidate multilib: .;@m64 Selected multilib: .;@m64 perf $ ./perf trace -e write --max-events=1 0.000 ( 0.009 ms): gmain/1448 write(fd: 4, buf: \1\0\0\0\0\0\0\0, count: 8) = 8 (kworker/0:0-eve) perf $ So lets make that the required version, if you happen to have a slightly older version where this work, please report so that we can adjust the minimum required version. Reported-by: Howard Chu Cc: Ian Rogers Cc: Adrian Hunter Cc: Alan Maguire Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/lkml/ZuGL9ROeTV2uXoSp@x1 Signed-off-by: Arnaldo Carvalho de Melo

perf build: Autodetect minimum required llvm-dev version

2024-09-10T20:32:46+00:00

The new LLVM addr2line feature requires a minimum version of 13 to compile. Add a feature check for the version so that NO_LLVM=1 doesn't need to be explicitly added. Leave the existing llvm feature check intact because it's used by tools other than Perf. This fixes the following compilation error when the llvm-dev version doesn't match: util/llvm-c-helpers.cpp: In function 'char* llvm_name_for_code(dso*, const char*, u64)': util/llvm-c-helpers.cpp:178:21: error: 'std::remove_reference_t' {aka 'struct llvm::DILineInfo'} has no member named 'StartAddress' 178 | addr, res_or_err->StartAddress ? *res_or_err->StartAddress : 0); Fixes: c3f8644c21df9b7d ("perf report: Support LLVM for addr2line()") Signed-off-by: James Clark Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Bill Wendling Cc: Changbin Du Cc: Guilherme Amadio Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Justin Stitt Cc: Kan Liang Cc: Leo Yan Cc: Manu Bretelle Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Quentin Monnet Cc: Steinar H. Gunderson Link: https://lore.kernel.org/r/20240910140405.568791-1-james.clark@linaro.org Signed-off-by: Arnaldo Carvalho de Melo

perf report: Support LLVM for addr2line()

2024-09-03T13:15:16+00:00

In addition to the existing support for libbfd and calling out to an external addr2line command, add support for using libllvm directly. This is both faster than libbfd, and can be enabled in distro builds (the LLVM license has an explicit provision for GPLv2 compatibility). Thus, it is set as the primary choice if available. As an example, running 'perf report' on a medium-size profile with DWARF-based backtraces took 58 seconds with LLVM, 78 seconds with libbfd, 153 seconds with external llvm-addr2line, and I got tired and aborted the test after waiting for 55 minutes with external bfd addr2line (which is the default for perf as compiled by distributions today). Evidently, for this case, the bfd addr2line process needs 18 seconds (on a 5.2 GHz Zen 3) to load the .debug ELF in question, hits the 1-second timeout and gets killed during initialization, getting restarted anew every time. Having an in-process addr2line makes this much more robust. As future extensions, libllvm can be used in many other places where we currently use libbfd or other libraries: - Symbol enumeration (in particular, for PE binaries). - Demangling (including non-Itanium demangling, e.g. Microsoft or Rust). - Disassembling (perf annotate). However, these are much less pressing; most people don't profile PE binaries, and perf has non-bfd paths for ELF. The same with demangling; the default _cxa_demangle path works fine for most users, and while bfd objdump can be slow on large binaries, it is possible to use --objdump=llvm-objdump to get the speed benefits. (It appears LLVM-based demangling is very simple, should we want that.) Tested with LLVM 14, 15, 16, 18 and 19. For some reason, LLVM 12 was not correctly detected using feature_check, and thus was not tested. Committer notes: Added the name and a __maybe_unused to address: 1 13.50 almalinux:8 : FAIL gcc version 8.5.0 20210514 (Red Hat 8.5.0-22) (GCC) util/srcline.c: In function 'dso__free_a2l': util/srcline.c:184:20: error: parameter name omitted void dso__free_a2l(struct dso *) ^~~~~~~~~~~~ make[3]: *** [/git/perf-6.11.0-rc3/tools/build/Makefile.build:158: util] Error 2 Signed-off-by: Steinar H. Gunderson Tested-by: Arnaldo Carvalho de Melo Cc: Ian Rogers Link: https://lore.kernel.org/r/20240803152008.2818485-1-sesse@google.com Signed-off-by: Arnaldo Carvalho de Melo