Re: [PATCH v9 perf,bpf 12/15] perf, bpf: enable annotation of bpf program

[Song Liu <songliubraving@fb.com>]

> On Mar 18, 2019, at 9:43 AM, Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com> wrote:
> 
> Em Mon, Mar 18, 2019 at 01:38:48PM -0300, Arnaldo Carvalho de Melo escreveu:
>> Em Mon, Mar 11, 2019 at 10:30:48PM -0700, Song Liu escreveu:
>>> This patch enables the annotation of bpf program.
>>> 
>>> A new dso type DSO_BINARY_TYPE__BPF_PROG_INFO is introduced to for BPF
>>> programs. In symbol__disassemble(), DSO_BINARY_TYPE__BPF_PROG_INFO dso
>>> calls into a new function symbol__disassemble_bpf(), where annotation
>>> line information is filled based bpf_prog_info and btf saved in given
>>> perf_env.
>>> 
>>> symbol__disassemble_bpf() uses libbfd to disassemble bpf programs.
>>> 
>>> Signed-off-by: Song Liu <songliubraving@fb.com>
>>> ---
>>> tools/build/Makefile.feature |   6 +-
>>> tools/perf/Makefile.config   |   4 +
>> 
>> I see the changes to these two files, but I can't see the feature test
>> that it triggers, forgot to do a git-add? Or is it in an upcoming patch
>> in this series?
>> 
>> After applying this test it "works":
>> 
>>  make: Entering directory '/home/acme/git/perf/tools/perf'
>>    BUILD:   Doing 'make -j8' parallel build
>> 
>>  Auto-detecting system features:
>>  ...                         dwarf: [ on  ]
>>  ...            dwarf_getlocations: [ on  ]
>>  <SNIP>
>>  ...                           bpf: [ on  ]
>>  ...                        libaio: [ on  ]
>>  ...        disassembler-four-args: [ on  ]
>> 
>> Because you added it to FEATURE_TESTS_BASIC, and this means that if
>> tools/build/feature/test-all.c builds, then what is in
>> FEATURE_TESTS_BASIC is set to 'on', but you didn't add anything to
>> tools/build/feature/test-all.c, so it works because all the other
>> features are present.
>> 
>> Take a look at:
>> 
>>  2a07d814747b ("tools build feature: Check if libaio is available")
>> 
>> To see what needs to be done.
>> 
>> Either way, its interesting to break this patch in two, one adding the
>> feature test and another to use it, i.e. the second patch out of this
>> should have the commit log message in this patch.
>> 
>> I've applied the patches up to before this one and will continue
>> processing other patches while you address this.
> 
> Ok, to continue processing the other patches I chunked out the part
> below into a 3rd patch from the above one and have it applied already.

Could you please push applied patches to the tmp.perf/bpf-annotation 
branch? 

Thanks,
Song

> 
> commit f326de312abc3657b0397817c66cd7e1540655f7
> Author: Song Liu <songliubraving@fb.com>
> Date:   Mon Mar 11 22:30:48 2019 -0700
> 
>    perf symbols: Introduce DSO_BINARY_TYPE__BPF_PROG_INFO
> 
>    Introduce a new dso type DSO_BINARY_TYPE__BPF_PROG_INFO for BPF programs. In
>    symbol__disassemble(), DSO_BINARY_TYPE__BPF_PROG_INFO dso will call into a new
>    function symbol__disassemble_bpf() in an upcoming patch, where annotation line
>    information is filled based bpf_prog_info and btf saved in given perf_env.
> 
>    Signed-off-by: Song Liu <songliubraving@fb.com>
>    Reviewed-by: Jiri Olsa <jolsa@kernel.org>
>    Cc: Alexei Starovoitov <ast@kernel.org>
>    Cc: Daniel Borkmann <daniel@iogearbox.net>
>    Cc: Namhyung Kim <namhyung@kernel.org>
>    Cc: Peter Zijlstra <peterz@infradead.org>
>    Cc: Stanislav Fomichev <sdf@google.com>
>    Cc: kernel-team@fb.com
>    Link: http://lkml.kernel.org/r/20190312053051.2690567-13-songliubraving@fb.com
>    [ split from a larger patch ]
>    Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
> index ba58ba603b69..58547c468c65 100644
> --- a/tools/perf/util/dso.c
> +++ b/tools/perf/util/dso.c
> @@ -184,6 +184,7 @@ int dso__read_binary_type_filename(const struct dso *dso,
> 	case DSO_BINARY_TYPE__KALLSYMS:
> 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
> 	case DSO_BINARY_TYPE__JAVA_JIT:
> +	case DSO_BINARY_TYPE__BPF_PROG_INFO:
> 	case DSO_BINARY_TYPE__NOT_FOUND:
> 		ret = -1;
> 		break;
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index bb417c54c25a..c274b5aa839d 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -14,6 +14,7 @@
> 
> struct machine;
> struct map;
> +struct perf_env;
> 
> enum dso_binary_type {
> 	DSO_BINARY_TYPE__KALLSYMS = 0,
> @@ -35,6 +36,7 @@ enum dso_binary_type {
> 	DSO_BINARY_TYPE__KCORE,
> 	DSO_BINARY_TYPE__GUEST_KCORE,
> 	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
> +	DSO_BINARY_TYPE__BPF_PROG_INFO,
> 	DSO_BINARY_TYPE__NOT_FOUND,
> };
> 
> @@ -178,17 +180,25 @@ struct dso {
> 	struct auxtrace_cache *auxtrace_cache;
> 	int		 comp;
> 
> -	/* dso data file */
> -	struct {
> -		struct rb_root	 cache;
> -		int		 fd;
> -		int		 status;
> -		u32		 status_seen;
> -		size_t		 file_size;
> -		struct list_head open_entry;
> -		u64		 debug_frame_offset;
> -		u64		 eh_frame_hdr_offset;
> -	} data;
> +	union {
> +		/* dso data file */
> +		struct {
> +			struct rb_root	 cache;
> +			int		 fd;
> +			int		 status;
> +			u32		 status_seen;
> +			size_t		 file_size;
> +			struct list_head open_entry;
> +			u64		 debug_frame_offset;
> +			u64		 eh_frame_hdr_offset;
> +		} data;
> +		/* bpf prog information */
> +		struct {
> +			u32		id;
> +			u32		sub_id;
> +			struct perf_env	*env;
> +		} bpf_prog;
> +	};
> 
> 	union { /* Tool specific area */
> 		void	 *priv;
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 58442ca5e3c4..5cbad55cd99d 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1455,6 +1455,7 @@ static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
> 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
> 		return true;
> 
> +	case DSO_BINARY_TYPE__BPF_PROG_INFO:
> 	case DSO_BINARY_TYPE__NOT_FOUND:
> 	default:
> 		return false;