[PATCH 00/12] perf tools: Display eBPF code in intel_pt trace

Jiri Olsa
2019-04-16T16:01:39Z

hi,
this patchset adds dso support to read and display
bpf code in intel_pt trace output. I had to change
some of the kernel maps processing code, so hopefully
I did not break too many things ;-)

It's now possible to see bpf code flow via:

# perf-with-kcore record pt -e intel_pt//ku -- sleep 1
# perf-with-kcore script pt --insn-trace --xed
...
sleep 36660 [016] 1057036.806464404: ffffffff811dfba5 trace_call_bpf+0x65 ([kernel.kallsyms]) nopl %eax, (%rax,%rax,1)
sleep 36660 [016] 1057036.806464404: ffffffff811dfbaa trace_call_bpf+0x6a ([kernel.kallsyms]) movq 0x30(%rbx), %rax
sleep 36660 [016] 1057036.806464404: ffffffff811dfbae trace_call_bpf+0x6e ([kernel.kallsyms]) leaq 0x38(%rbx), %rsi
sleep 36660 [016] 1057036.806464404: ffffffff811dfbb2 trace_call_bpf+0x72 ([kernel.kallsyms]) mov %r13, %rdi
sleep 36660 [016] 1057036.806464404: ffffffff811dfbb5 trace_call_bpf+0x75 ([kernel.kallsyms]) callq 0xffffffff81c00c30
sleep 36660 [016] 1057036.806464404: ffffffff81c00c30 __x86_indirect_thunk_rax+0x0 ([kernel.kallsyms]) callq 0xffffffff81c00c3c
sleep 36660 [016] 1057036.806464404: ffffffff81c00c3c __x86_indirect_thunk_rax+0xc ([kernel.kallsyms]) movq %rax, (%rsp)
sleep 36660 [016] 1057036.806464404: ffffffff81c00c40 __x86_indirect_thunk_rax+0x10 ([kernel.kallsyms]) retq
sleep 36660 [016] 1057036.806464725: ffffffffa05e89ef bpf_prog_da4fe6b3d2c29b25_trace_return+0x0 (bpf_prog_da4fe6b3d2c29b25_trace_return) pushq %rbp
sleep 36660 [016] 1057036.806464725: ffffffffa05e89f0 bpf_prog_da4fe6b3d2c29b25_trace_return+0x1 (bpf_prog_da4fe6b3d2c29b25_trace_return) mov %rsp, %rbp
sleep 36660 [016] 1057036.806464725: ffffffffa05e89f3 bpf_prog_da4fe6b3d2c29b25_trace_return+0x4 (bpf_prog_da4fe6b3d2c29b25_trace_return) sub $0x158, %rsp
sleep 36660 [016] 1057036.806464725: ffffffffa05e89fa bpf_prog_da4fe6b3d2c29b25_trace_return+0xb (bpf_prog_da4fe6b3d2c29b25_trace_return) sub $0x28, %rbp
sleep 36660 [016] 1057036.806464725: ffffffffa05e89fe bpf_prog_da4fe6b3d2c29b25_trace_return+0xf (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %rbx, (%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a02 bpf_prog_da4fe6b3d2c29b25_trace_return+0x13 (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %r13, 0x8(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a06 bpf_prog_da4fe6b3d2c29b25_trace_return+0x17 (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %r14, 0x10(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a0a bpf_prog_da4fe6b3d2c29b25_trace_return+0x1b (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %r15, 0x18(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a0e bpf_prog_da4fe6b3d2c29b25_trace_return+0x1f (bpf_prog_da4fe6b3d2c29b25_trace_return) xor %eax, %eax
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a10 bpf_prog_da4fe6b3d2c29b25_trace_return+0x21 (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %rax, 0x20(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a14 bpf_prog_da4fe6b3d2c29b25_trace_return+0x25 (bpf_prog_da4fe6b3d2c29b25_trace_return) mov %rdi, %rbx
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a17 bpf_prog_da4fe6b3d2c29b25_trace_return+0x28 (bpf_prog_da4fe6b3d2c29b25_trace_return) callq 0xffffffff811fed50
sleep 36660 [016] 1057036.806464725: ffffffff811fed50 bpf_get_current_pid_tgid+0x0 ([kernel.kallsyms]) nopl %eax, (%rax,%rax,1)
sleep 36660 [016] 1057036.806464725: ffffffff811fed55 bpf_get_current_pid_tgid+0x5 ([kernel.kallsyms]) movq %gs:0x15c00, %rdx
sleep 36660 [016] 1057036.806464725: ffffffff811fed5e bpf_get_current_pid_tgid+0xe ([kernel.kallsyms]) test %rdx, %rdx
sleep 36660 [016] 1057036.806464725: ffffffff811fed61 bpf_get_current_pid_tgid+0x11 ([kernel.kallsyms]) jz 0xffffffff811fed79
sleep 36660 [016] 1057036.806464725: ffffffff811fed63 bpf_get_current_pid_tgid+0x13 ([kernel.kallsyms]) movsxdl 0x494(%rdx), %rax
sleep 36660 [016] 1057036.806464725: ffffffff811fed6a bpf_get_current_pid_tgid+0x1a ([kernel.kallsyms]) movsxdl 0x490(%rdx), %rdx
sleep 36660 [016] 1057036.806464725: ffffffff811fed71 bpf_get_current_pid_tgid+0x21 ([kernel.kallsyms]) shl $0x20, %rax
sleep 36660 [016] 1057036.806464725: ffffffff811fed75 bpf_get_current_pid_tgid+0x25 ([kernel.kallsyms]) or %rdx, %rax
sleep 36660 [016] 1057036.806464725: ffffffff811fed78 bpf_get_current_pid_tgid+0x28 ([kernel.kallsyms]) retq
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a1c bpf_prog_da4fe6b3d2c29b25_trace_return+0x2d (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %rax, -0x8(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a20 bpf_prog_da4fe6b3d2c29b25_trace_return+0x31 (bpf_prog_da4fe6b3d2c29b25_trace_return) xor %edi, %edi
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a22 bpf_prog_da4fe6b3d2c29b25_trace_return+0x33 (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %rdi, -0x10(%rbp)
sleep 36660 [016] 1057036.806464725: ffffffffa05e8a26 bpf_prog_da4fe6b3d2c29b25_trace_return+0x37 (bpf_prog_da4fe6b3d2c29b25_trace_return) movq %rdi, -0x18(%rbp)

# perf-core/perf-with-kcore script pt --call-trace
...
sleep 36660 [016] 1057036.806464404: ([kernel.kallsyms] ) kretprobe_perf_func
sleep 36660 [016] 1057036.806464404: ([kernel.kallsyms] ) trace_call_bpf
sleep 36660 [016] 1057036.806464404: ([kernel.kallsyms] ) __x86_indirect_thunk_rax
sleep 36660 [016] 1057036.806464404: ([kernel.kallsyms] ) __x86_indirect_thunk_rax
sleep 36660 [016] 1057036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_get_current_pid_tgid
sleep 36660 [016] 1057036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_ktime_get_ns
sleep 36660 [016] 1057036.806464725: ([kernel.kallsyms] ) __x86_indirect_thunk_rax
sleep 36660 [016] 1057036.806464725: ([kernel.kallsyms] ) __x86_indirect_thunk_rax
sleep 36660 [016] 1057036.806465045: (bpf_prog_da4fe6b3d2c29b25_trace_return ) __htab_map_lookup_elem
sleep 36660 [016] 1057036.806465366: ([kernel.kallsyms] ) memcmp
sleep 36660 [016] 1057036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_probe_read
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) probe_kernel_read
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) __check_object_size
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) check_stack_object
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) copy_user_enhanced_fast_string
sleep 36660 [016] 1057036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_probe_read
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) probe_kernel_read
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) __check_object_size
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) check_stack_object
sleep 36660 [016] 1057036.806465687: ([kernel.kallsyms] ) copy_user_enhanced_fast_string
sleep 36660 [016] 1057036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_get_current_uid_gid
sleep 36660 [016] 1057036.806466008: ([kernel.kallsyms] ) from_kgid
sleep 36660 [016] 1057036.806466008: ([kernel.kallsyms] ) from_kuid
sleep 36660 [016] 1057036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return ) bpf_perf_event_output
sleep 36660 [016] 1057036.806466328: ([kernel.kallsyms] ) perf_event_output
sleep 36660 [016] 1057036.806466328: ([kernel.kallsyms] ) perf_prepare_sample
sleep 36660 [016] 1057036.806466328: ([kernel.kallsyms] ) perf_misc_flags
sleep 36660 [016] 1057036.806466328: ([kernel.kallsyms] ) __x86_indirect_thunk_rax
sleep 36660 [016] 1057036.806466328: ([kernel.kallsyms] ) __x86_indirect_thunk_rax

It's also available in here:
git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
perf/fixes

thanks,
jirka

Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Stanislav Fomichev <sdf@google.com>
---
Jiri Olsa (11):
perf tools: Separate generic code in dso__data_file_size
perf tools: Separate generic code in dso_cache__read
perf tools: Simplify dso_cache__read function
perf tools: Add bpf dso read and size hooks
perf tools: Read also the end of the kernel
perf tools: Do not erase uncovered maps by kcore
perf tools: Fix side band thread draining
perf tools: Fix map reference counting
perf tools: Keep zero in pgoff bpf map
perf tools: Reuse shared eBPF dso objects
perf script: Pad dso name for --call-trace

Song Liu (1):
perf tools: Check maps for bpf programs

tools/include/linux/kernel.h | 1 +
tools/lib/vsprintf.c | 19 +++++++++++++++++++
tools/perf/builtin-script.c | 1 +
tools/perf/util/dso.c | 124 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------------------------------
tools/perf/util/evlist.c | 14 +++++++++-----
tools/perf/util/machine.c | 45 +++++++++++++++++++++++++++++++--------------
tools/perf/util/map.c | 26 +++++++++++++++++++++++---
tools/perf/util/map.h | 4 +++-
tools/perf/util/symbol.c | 14 +++++++++++++-
tools/perf/util/symbol_conf.h | 1 +
tools/perf/util/symbol_fprintf.c | 1 +
11 files changed, 190 insertions(+), 60 deletions(-)