Em Mon, May 17, 2021 at 08:06:30PM +0800, 程书意 escreveu:
> To solve problems similar to _RH_KABI_REPLACE, _RH_KABI_REPLACE makes many
Can you explain what is _RH_KABI_REPLACE, why it is needed so that
people unfamiliar with it can make sense of your patch?
Also why "btf_prefix" when this is related to this other feature? Can
you find a better name?
You also forgot to update the man page at man-pages/pahole.1.
- Arnaldo
> structures have different names, resulting in a
> particularly large vmlinux btf. For example, running ./pahole -J
> vmlinux-3.10.0-1160.el7.x86_64 without --btf_prefix flag,
> the running time is:
> real 8m28.912s
> user 8m27.271s
> sys 0m1.471s
> And the size of the generated btf segment is 30678240 bytes.
>
> After adding the patch, running ./pahole
> --btf_prefix=__UNIQUE_ID_rh_kabi_hide -J vmlinux-3.10.0-1160.el7.x86_64. The
> running
> time of the command is:
> real 0m19.634s
> user 0m18.457s
> sys 0m1.169s
> The size of the generated btf segment is 3117719 bytes.
>
> Thanks.
>
> Signed-off-by: chengshuyi <chengshuyi@xxxxxxxxxxxxxxxxx>
> ---
> pahole.c | 10 ++++++++++
> pahole_strings.h | 2 ++
> strings.c | 9 +++++++--
> 3 files changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/pahole.c b/pahole.c
> index dc40ccf..0b4f4ca 100644
> --- a/pahole.c
> +++ b/pahole.c
> @@ -24,6 +24,7 @@
> #include "btf_encoder.h"
> #include "libbtf.h"
> #include "lib/bpf/src/libbpf.h"
> +#include "pahole_strings.h"
>
> static bool btf_encode;
> static bool ctf_encode;
> @@ -855,6 +856,7 @@ ARGP_PROGRAM_VERSION_HOOK_DEF = dwarves_print_version;
> #define ARGP_btf_gen_floats 322
> #define ARGP_btf_gen_all 323
> #define ARGP_with_flexible_array 324
> +#define ARGP_btf_prefix 325
>
> static const struct argp_option pahole__options[] = {
> {
> @@ -1140,6 +1142,12 @@ static const struct argp_option pahole__options[] = {
> .doc = "Path to the base BTF file",
> },
> {
> + .name = "btf_prefix",
> + .key = ARGP_btf_prefix,
> + .arg = "STRING",
> + .doc = "Strings with the same prefix are considered the same.",
> + },
> + {
> .name = "btf_encode",
> .key = 'J',
> .doc = "Encode as BTF",
> @@ -1297,6 +1305,8 @@ static error_t pahole__options_parser(int key, char
> *arg,
> btf_encode_force = true; break;
> case ARGP_btf_base:
> base_btf_file = arg; break;
> + case ARGP_btf_prefix:
> + btf_prefix = arg; break;
> case ARGP_numeric_version:
> print_numeric_version = true; break;
> case ARGP_btf_gen_floats:
> diff --git a/pahole_strings.h b/pahole_strings.h
> index 522fbf2..bf3dc7c 100644
> --- a/pahole_strings.h
> +++ b/pahole_strings.h
> @@ -14,6 +14,8 @@ struct strings {
> struct btf *btf;
> };
>
> +extern const char *btf_prefix;
> +
> struct strings *strings__new(void);
>
> void strings__delete(struct strings *strings);
> diff --git a/strings.c b/strings.c
> index d37f49d..911ce25 100644
> --- a/strings.c
> +++ b/strings.c
> @@ -16,6 +16,9 @@
>
> #include "dutil.h"
> #include "lib/bpf/src/libbpf.h"
> +#include "libbtf.h"
Why do you need to add this new include? I guess you meant including
pahole_strings.h to get the forward declaration for 'btf_prefix'?
> +
> +const char *btf_prefix;
>
> struct strings *strings__new(void)
> {
> @@ -47,8 +50,10 @@ strings_t strings__add(struct strings *strs, const char
> *str)
>
> if (str == NULL)
> return 0;
> -
> - index = btf__add_str(strs->btf, str);
> + if(btf_prefix && strncmp(str,btf_prefix,strlen(btf_prefix))==0)
Please also follow the existing coding style, i.e. use a space after
'if' and also after the commas.
- Arnaldo
> + index = btf__add_str(strs->btf, btf_prefix);
> + else
> + index = btf__add_str(strs->btf, str);
> if (index < 0)
> return 0;
>
> --
> 1.8.3.1
>
>
--
- Arnaldo
