d509db0473
This patch provides infrastructure for passing source files to --event
directly using:
# perf record --event bpf-file.c command
This patch does following works:
1) Allow passing '.c' file to '--event'. parse_events_load_bpf() is
expanded to allow caller tell it whether the passed file is source
file or object.
2) llvm__compile_bpf() is called to compile the '.c' file, the result
is saved into memory. Use bpf_object__open_buffer() to load the
in-memory object.
Introduces a bpf-script-example.c so we can manually test it:
# perf record --clang-opt "-DLINUX_VERSION_CODE=0x40200" --event ./bpf-script-example.c sleep 1
Note that '--clang-opt' must put before '--event'.
Futher patches will merge it into a testcase so can be tested automatically.
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/r/1444826502-49291-10-git-send-email-wangnan0@huawei.com
Signed-off-by: He Kuang <hekuang@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
45 lines
1.2 KiB
C
45 lines
1.2 KiB
C
#ifndef LINUX_VERSION_CODE
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# error Need LINUX_VERSION_CODE
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# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
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#endif
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#define BPF_ANY 0
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#define BPF_MAP_TYPE_ARRAY 2
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#define BPF_FUNC_map_lookup_elem 1
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#define BPF_FUNC_map_update_elem 2
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static void *(*bpf_map_lookup_elem)(void *map, void *key) =
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(void *) BPF_FUNC_map_lookup_elem;
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static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) =
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(void *) BPF_FUNC_map_update_elem;
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struct bpf_map_def {
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unsigned int type;
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unsigned int key_size;
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unsigned int value_size;
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unsigned int max_entries;
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};
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#define SEC(NAME) __attribute__((section(NAME), used))
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struct bpf_map_def SEC("maps") flip_table = {
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.type = BPF_MAP_TYPE_ARRAY,
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.key_size = sizeof(int),
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.value_size = sizeof(int),
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.max_entries = 1,
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};
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SEC("func=sys_epoll_pwait")
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int bpf_func__sys_epoll_pwait(void *ctx)
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{
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int ind =0;
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int *flag = bpf_map_lookup_elem(&flip_table, &ind);
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int new_flag;
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if (!flag)
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return 0;
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/* flip flag and store back */
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new_flag = !*flag;
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bpf_map_update_elem(&flip_table, &ind, &new_flag, BPF_ANY);
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return new_flag;
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}
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char _license[] SEC("license") = "GPL";
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int _version SEC("version") = LINUX_VERSION_CODE;
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