From 7efe0e034c713716060bc7794c7e332589980c70 Mon Sep 17 00:00:00 2001 From: He Kuang Date: Mon, 14 Dec 2015 10:39:23 +0000 Subject: [PATCH] perf record: Support custom vmlinux path Make perf-record command support --vmlinux option if BPF_PROLOGUE is on. 'perf record' needs vmlinux as the source of DWARF info to generate prologue for BPF programs, so path of vmlinux should be specified. Short name 'k' has been taken by 'clockid'. This patch skips the short option name and uses '--vmlinux' for vmlinux path. Documentation is also updated. Test result: In a production (or broken) environment: (by: # rm -rf ~/.debug/ # mv /lib/modules/`uname -r`/build/vmlinux /tmp/ ) # ./perf record -e ./test_bpf_base.c ls Failed to find the path for kernel: No such file or directory event syntax error: './test_bpf_base.c' \___ You need to check probing points in BPF file ... # ./perf record --vmlinux /tmp/vmlinux -e ./test_bpf_base.c ls ... [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.011 MB perf.data ] Help messages when build with NO_LIBBPF: # ./perf record -h --transaction sample transaction flags (special events only) --vmlinux vmlinux pathname (not built-in because NO_LIBBPF=1) # ./perf record --vmlinux /tmp/vmlinux ls / Warning: option `vmlinux' is being ignored because NO_LIBBPF=1 ... [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.011 MB perf.data (11 samples) ] Help messages when build with NO_DWARF: # ./perf record -h --transaction sample transaction flags (special events only) --vmlinux vmlinux pathname (not built-in because NO_DWARF=1) Signed-off-by: He Kuang Cc: Alexei Starovoitov Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Wang Nan Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1450089563-122430-15-git-send-email-wangnan0@huawei.com Signed-off-by: Wang Nan Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-record.txt | 10 ++++++++-- tools/perf/builtin-record.c | 16 ++++++++++++++++ 2 files changed, 24 insertions(+), 2 deletions(-) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index e630a7d2c348..8d032f4e50bf 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -314,11 +314,17 @@ This option sets the time out limit. The default value is 500 ms. Record context switch events i.e. events of type PERF_RECORD_SWITCH or PERF_RECORD_SWITCH_CPU_WIDE. ---clang-path:: +--clang-path=PATH:: Path to clang binary to use for compiling BPF scriptlets. +(enabled when BPF support is on) ---clang-opt:: +--clang-opt=OPTIONS:: Options passed to clang when compiling BPF scriptlets. +(enabled when BPF support is on) + +--vmlinux=PATH:: +Specify vmlinux path which has debuginfo. +(enabled when BPF prologue is on) SEE ALSO -------- diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index c2ba377e8d3a..3ef3c79e7534 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1117,6 +1117,8 @@ struct option __record_options[] = { "clang binary to use for compiling BPF scriptlets"), OPT_STRING(0, "clang-opt", &llvm_param.clang_opt, "clang options", "options passed to clang when compiling BPF scriptlets"), + OPT_STRING(0, "vmlinux", &symbol_conf.vmlinux_name, + "file", "vmlinux pathname"), OPT_END() }; @@ -1133,6 +1135,20 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused) set_nobuild('\0', "clang-path", true); set_nobuild('\0', "clang-opt", true); # undef set_nobuild +#endif + +#ifndef HAVE_BPF_PROLOGUE +# if !defined (HAVE_DWARF_SUPPORT) +# define REASON "NO_DWARF=1" +# elif !defined (HAVE_LIBBPF_SUPPORT) +# define REASON "NO_LIBBPF=1" +# else +# define REASON "this architecture doesn't support BPF prologue" +# endif +# define set_nobuild(s, l, c) set_option_nobuild(record_options, s, l, REASON, c) + set_nobuild('\0', "vmlinux", true); +# undef set_nobuild +# undef REASON #endif rec->evlist = perf_evlist__new(); -- 2.20.1