Add the --encode_all_btf_vars option, which conflicts with
--skip_encoding_btf_vars, and will enable encoding all variables which
have a corresponding STT_OBJECT match in the ELF symbol table. Rework
the btf_encoder_new() signature to include a single enum to specify
which kinds of variables are allowed, and add the necessary logic to
select variables.
Signed-off-by: Stephen Brennan <stephen.s.brennan@xxxxxxxxxx>
---
btf_encoder.c | 22 +++++++++++++---------
btf_encoder.h | 8 +++++++-
man-pages/pahole.1 | 6 +++++-
pahole.c | 31 +++++++++++++++++++++++++------
4 files changed, 50 insertions(+), 17 deletions(-)
diff --git a/btf_encoder.c b/btf_encoder.c
index 1804500..eabc8d2 100644
--- a/btf_encoder.c
+++ b/btf_encoder.c
@@ -61,7 +61,6 @@ struct btf_encoder {
struct elf_symtab *symtab;
bool has_index_type,
need_index_type,
- skip_encoding_vars,
raw_output,
verbose,
force,
@@ -70,6 +69,7 @@ struct btf_encoder {
uint32_t array_index_id;
struct elf_secinfo secinfo[MAX_ELF_SEC_CNT];
size_t seccnt;
+ enum btf_var_option encode_vars;
struct {
struct var_info *vars;
int var_cnt;
@@ -1198,24 +1198,25 @@ static int btf_encoder__collect_var(struct btf_encoder *encoder, GElf_Sym *sym,
return 0;
}
-static int btf_encoder__collect_symbols(struct btf_encoder *encoder, bool collect_percpu_vars)
+static int btf_encoder__collect_symbols(struct btf_encoder *encoder)
{
uint32_t sym_sec_idx;
uint32_t core_id;
GElf_Sym sym;
+ bool collect_vars = (encoder->encode_vars != BTF_VAR_NONE);
/* cache variables' addresses, preparing for searching in symtab. */
encoder->variables.var_cnt = 0;
/* search within symtab for percpu variables */
elf_symtab__for_each_symbol_index(encoder->symtab, core_id, sym, sym_sec_idx) {
- if (collect_percpu_vars && btf_encoder__collect_var(encoder, &sym, sym_sec_idx))
+ if (collect_vars && btf_encoder__collect_var(encoder, &sym, sym_sec_idx))
return -1;
if (btf_encoder__collect_function(encoder, &sym))
return -1;
}
- if (collect_percpu_vars) {
+ if (collect_vars) {
if (encoder->variables.var_cnt)
qsort(encoder->variables.vars, encoder->variables.var_cnt, sizeof(encoder->variables.vars[0]), var_cmp);
@@ -1375,7 +1376,7 @@ out:
return err;
}
-struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filename, struct btf *base_btf, bool skip_encoding_vars, bool force, bool gen_floats, bool verbose)
+struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filename, struct btf *base_btf, enum btf_var_option vars, bool force, bool gen_floats, bool verbose)
{
struct btf_encoder *encoder = zalloc(sizeof(*encoder));
@@ -1391,11 +1392,11 @@ struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filenam
encoder->force = force;
encoder->gen_floats = gen_floats;
- encoder->skip_encoding_vars = skip_encoding_vars;
encoder->verbose = verbose;
encoder->has_index_type = false;
encoder->need_index_type = false;
encoder->array_index_id = 0;
+ encoder->encode_vars = vars;
GElf_Ehdr ehdr;
@@ -1445,17 +1446,20 @@ struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filenam
encoder->secinfo[shndx].addr = shdr.sh_addr;
encoder->secinfo[shndx].sz = shdr.sh_size;
encoder->secinfo[shndx].name = secname;
+ if (encoder->encode_vars == BTF_VAR_ALL)
+ encoder->secinfo[shndx].include = true;
if (strcmp(secname, PERCPU_SECTION) == 0) {
encoder->variables.percpu_shndx = shndx;
- encoder->secinfo[shndx].include = true;
+ if (encoder->encode_vars != BTF_VAR_NONE)
+ encoder->secinfo[shndx].include = true;
}
}
if (!encoder->variables.percpu_shndx && encoder->verbose)
printf("%s: '%s' doesn't have '%s' section\n", __func__, cu->filename, PERCPU_SECTION);
- if (btf_encoder__collect_symbols(encoder, !encoder->skip_encoding_vars))
+ if (btf_encoder__collect_symbols(encoder))
goto out_delete;
if (encoder->verbose)
@@ -1615,7 +1619,7 @@ int btf_encoder__encode_cu(struct btf_encoder *encoder, struct cu *cu, struct co
}
}
- if (!encoder->skip_encoding_vars)
+ if (encoder->encode_vars != BTF_VAR_NONE)
err = btf_encoder__encode_cu_variables(encoder, cu, type_id_off);
out:
return err;
diff --git a/btf_encoder.h b/btf_encoder.h
index a65120c..e03c7cc 100644
--- a/btf_encoder.h
+++ b/btf_encoder.h
@@ -16,7 +16,13 @@ struct btf;
struct cu;
struct list_head;
-struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filename, struct btf *base_btf, bool skip_encoding_vars, bool force, bool gen_floats, bool verbose);
+enum btf_var_option {
+ BTF_VAR_NONE,
+ BTF_VAR_PERCPU,
+ BTF_VAR_ALL,
+};
+
+struct btf_encoder *btf_encoder__new(struct cu *cu, const char *detached_filename, struct btf *base_btf, enum btf_var_option vars, bool force, bool gen_floats, bool verbose);
void btf_encoder__delete(struct btf_encoder *encoder);
int btf_encoder__encode(struct btf_encoder *encoder);
diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
index bb88e2f..d21af0a 100644
--- a/man-pages/pahole.1
+++ b/man-pages/pahole.1
@@ -207,7 +207,11 @@ the debugging information.
.TP
.B \-\-skip_encoding_btf_vars
-Do not encode VARs in BTF.
+.TQ
+.B \-\-encode_all_btf_vars
+By default, VARs are encoded only for percpu variables. These options allow
+to skip encoding them, or to encode all variables regardless of whether they are
+percpu. These options are mutually exclusive.
.TP
.B \-\-skip_encoding_btf_decl_tag
diff --git a/pahole.c b/pahole.c
index e87d9a4..1f86ffb 100644
--- a/pahole.c
+++ b/pahole.c
@@ -4,6 +4,7 @@
Copyright (C) 2006 Mandriva Conectiva S.A.
Copyright (C) 2006 Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxx>
Copyright (C) 2007- Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
+ Copyright (c) 2022 Oracle and/or its affiliates.
*/
#include <argp.h>
@@ -37,7 +38,7 @@ static bool ctf_encode;
static bool sort_output;
static bool need_resort;
static bool first_obj_only;
-static bool skip_encoding_btf_vars;
+static enum btf_var_option encode_btf_vars = BTF_VAR_PERCPU;
static bool btf_encode_force;
static const char *base_btf_file;
@@ -1221,6 +1222,7 @@ ARGP_PROGRAM_VERSION_HOOK_DEF = dwarves_print_version;
#define ARGP_languages 335
#define ARGP_languages_exclude 336
#define ARGP_skip_encoding_btf_enum64 337
+#define ARGP_encode_all_btf_vars 338
static const struct argp_option pahole__options[] = {
{
@@ -1532,7 +1534,12 @@ static const struct argp_option pahole__options[] = {
{
.name = "skip_encoding_btf_vars",
.key = ARGP_skip_encoding_btf_vars,
- .doc = "Do not encode VARs in BTF."
+ .doc = "Do not encode any VARs in BTF (default: only percpu)."
+ },
+ {
+ .name = "encode_all_btf_vars",
+ .key = ARGP_encode_all_btf_vars,
+ .doc = "Encode all VARs in BTF (default: only percpu)."
},
{
.name = "btf_encode_force",
@@ -1757,8 +1764,6 @@ static error_t pahole__options_parser(int key, char *arg,
conf.range = arg; break;
case ARGP_header_type:
conf.header_type = arg; break;
- case ARGP_skip_encoding_btf_vars:
- skip_encoding_btf_vars = true; break;
case ARGP_btf_encode_force:
btf_encode_force = true; break;
case ARGP_btf_base:
@@ -1795,6 +1800,20 @@ static error_t pahole__options_parser(int key, char *arg,
languages.str = arg; break;
case ARGP_skip_encoding_btf_enum64:
conf_load.skip_encoding_btf_enum64 = true; break;
+ case ARGP_skip_encoding_btf_vars:
+ if (encode_btf_vars != BTF_VAR_PERCPU) {
+ fprintf(stderr, "error: --encode_all_btf_vars and --skip_encoding_btf_vars are mutually exclusive\n");
+ return ARGP_HELP_SEE;
+ }
+ encode_btf_vars = BTF_VAR_NONE;
+ break;
+ case ARGP_encode_all_btf_vars:
+ if (encode_btf_vars != BTF_VAR_PERCPU) {
+ fprintf(stderr, "error: --encode_all_btf_vars and --skip_encoding_btf_vars are mutually exclusive\n");
+ return ARGP_HELP_SEE;
+ }
+ encode_btf_vars = BTF_VAR_ALL;
+ break;
default:
return ARGP_ERR_UNKNOWN;
}
@@ -3034,7 +3053,7 @@ static enum load_steal_kind pahole_stealer(struct cu *cu,
* And, it is used by the thread
* create it.
*/
- btf_encoder = btf_encoder__new(cu, detached_btf_filename, conf_load->base_btf, skip_encoding_btf_vars,
+ btf_encoder = btf_encoder__new(cu, detached_btf_filename, conf_load->base_btf, encode_btf_vars,
btf_encode_force, btf_gen_floats, global_verbose);
if (btf_encoder && thr_data) {
struct thread_data *thread = thr_data;
@@ -3064,7 +3083,7 @@ static enum load_steal_kind pahole_stealer(struct cu *cu,
thread->encoder =
btf_encoder__new(cu, detached_btf_filename,
NULL,
- skip_encoding_btf_vars,
+ encode_btf_vars,
btf_encode_force,
btf_gen_floats,
global_verbose);
--
2.34.1
