[PATCH 16/22] objtool: Get rid of reloc->addend

From: Josh Poimboeuf
Date: Tue May 30 2023 - 13:22:46 EST

Get the addend from the embedded GElf_Rel[a] struct.

With allyesconfig + CONFIG_DEBUG_INFO:

- Before: peak heap memory consumption: 42.10G
- After: peak heap memory consumption: 40.37G

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
tools/objtool/arch/x86/decode.c | 4 +-
tools/objtool/arch/x86/special.c | 2 +-
tools/objtool/check.c | 69 +++++++++++++++++------------
tools/objtool/elf.c | 10 ++---
tools/objtool/include/objtool/elf.h | 6 ++-
tools/objtool/special.c | 4 +-
6 files changed, 53 insertions(+), 42 deletions(-)

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index ffb12e83b238..2e1caabecb18 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -623,11 +623,11 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
if (!immr || strcmp(immr->sym->name, "pv_ops"))
break;

- idx = (immr->addend + 8) / sizeof(void *);
+ idx = (reloc_addend(immr) + 8) / sizeof(void *);

func = disp->sym;
if (disp->sym->type == STT_SECTION)
- func = find_symbol_by_offset(disp->sym->sec, disp->addend);
+ func = find_symbol_by_offset(disp->sym->sec, reloc_addend(disp));
if (!func) {
WARN("no func for pv_ops[]");
return -1;
diff --git a/tools/objtool/arch/x86/special.c b/tools/objtool/arch/x86/special.c
index 1a54a249cb50..65f48f35b97e 100644
--- a/tools/objtool/arch/x86/special.c
+++ b/tools/objtool/arch/x86/special.c
@@ -105,7 +105,7 @@ struct reloc *arch_find_switch_table(struct objtool_file *file,
!text_reloc->sym->sec->rodata)
return NULL;

- table_offset = text_reloc->addend;
+ table_offset = reloc_addend(text_reloc);
table_sec = text_reloc->sym->sec;

if (reloc_type(text_reloc) == R_X86_64_PC32)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 1d794d15bc53..12a9e6fb3fe7 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -508,7 +508,8 @@ static int add_pv_ops(struct objtool_file *file, const char *symname)

func = reloc->sym;
if (func->type == STT_SECTION)
- func = find_symbol_by_offset(reloc->sym->sec, reloc->addend);
+ func = find_symbol_by_offset(reloc->sym->sec,
+ reloc_addend(reloc));

idx = (reloc_offset(reloc) - sym->offset) / sizeof(unsigned long);

@@ -582,6 +583,7 @@ static int add_dead_ends(struct objtool_file *file)
struct section *rsec;
struct reloc *reloc;
struct instruction *insn;
+ s64 addend;

/*
* Check for manually annotated dead ends.
@@ -591,23 +593,27 @@ static int add_dead_ends(struct objtool_file *file)
goto reachable;

for_each_reloc(rsec, reloc) {
+
if (reloc->sym->type != STT_SECTION) {
WARN("unexpected relocation symbol type in %s", rsec->name);
return -1;
}
- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+
+ addend = reloc_addend(reloc);
+
+ insn = find_insn(file, reloc->sym->sec, addend);
if (insn)
insn = prev_insn_same_sec(file, insn);
- else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
+ else if (addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
WARN("can't find unreachable insn at %s+0x%" PRIx64,
- reloc->sym->sec->name, reloc->addend);
+ reloc->sym->sec->name, addend);
return -1;
}
} else {
WARN("can't find unreachable insn at %s+0x%" PRIx64,
- reloc->sym->sec->name, reloc->addend);
+ reloc->sym->sec->name, addend);
return -1;
}

@@ -626,23 +632,27 @@ static int add_dead_ends(struct objtool_file *file)
return 0;

for_each_reloc(rsec, reloc) {
+
if (reloc->sym->type != STT_SECTION) {
WARN("unexpected relocation symbol type in %s", rsec->name);
return -1;
}
- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+
+ addend = reloc_addend(reloc);
+
+ insn = find_insn(file, reloc->sym->sec, addend);
if (insn)
insn = prev_insn_same_sec(file, insn);
- else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
+ else if (addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
WARN("can't find reachable insn at %s+0x%" PRIx64,
- reloc->sym->sec->name, reloc->addend);
+ reloc->sym->sec->name, addend);
return -1;
}
} else {
WARN("can't find reachable insn at %s+0x%" PRIx64,
- reloc->sym->sec->name, reloc->addend);
+ reloc->sym->sec->name, addend);
return -1;
}

@@ -1025,7 +1035,7 @@ static void add_ignores(struct objtool_file *file)
break;

case STT_SECTION:
- func = find_func_by_offset(reloc->sym->sec, reloc->addend);
+ func = find_func_by_offset(reloc->sym->sec, reloc_addend(reloc));
if (!func)
continue;
break;
@@ -1265,7 +1275,7 @@ static int add_ignore_alternatives(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.ignore_alts entry");
return -1;
@@ -1541,7 +1551,7 @@ static int add_jump_destinations(struct objtool_file *file)
dest_off = arch_jump_destination(insn);
} else if (reloc->sym->type == STT_SECTION) {
dest_sec = reloc->sym->sec;
- dest_off = arch_dest_reloc_offset(reloc->addend);
+ dest_off = arch_dest_reloc_offset(reloc_addend(reloc));
} else if (reloc->sym->retpoline_thunk) {
add_retpoline_call(file, insn);
continue;
@@ -1558,7 +1568,7 @@ static int add_jump_destinations(struct objtool_file *file)
} else if (reloc->sym->sec->idx) {
dest_sec = reloc->sym->sec;
dest_off = reloc->sym->sym.st_value +
- arch_dest_reloc_offset(reloc->addend);
+ arch_dest_reloc_offset(reloc_addend(reloc));
} else {
/* non-func asm code jumping to another file */
continue;
@@ -1675,7 +1685,7 @@ static int add_call_destinations(struct objtool_file *file)
}

} else if (reloc->sym->type == STT_SECTION) {
- dest_off = arch_dest_reloc_offset(reloc->addend);
+ dest_off = arch_dest_reloc_offset(reloc_addend(reloc));
dest = find_call_destination(reloc->sym->sec, dest_off);
if (!dest) {
WARN_INSN(insn, "can't find call dest symbol at %s+0x%lx",
@@ -2002,10 +2012,10 @@ static int add_jump_table(struct objtool_file *file, struct instruction *insn,

/* Detect function pointers from contiguous objects: */
if (reloc->sym->sec == pfunc->sec &&
- reloc->addend == pfunc->offset)
+ reloc_addend(reloc) == pfunc->offset)
break;

- dest_insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ dest_insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!dest_insn)
break;

@@ -2066,7 +2076,7 @@ static struct reloc *find_jump_table(struct objtool_file *file,
table_reloc = arch_find_switch_table(file, insn);
if (!table_reloc)
continue;
- dest_insn = find_insn(file, table_reloc->sym->sec, table_reloc->addend);
+ dest_insn = find_insn(file, table_reloc->sym->sec, reloc_addend(table_reloc));
if (!dest_insn || !insn_func(dest_insn) || insn_func(dest_insn)->pfunc != func)
continue;

@@ -2202,7 +2212,7 @@ static int read_unwind_hints(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("can't find insn for unwind_hints[%d]", i);
return -1;
@@ -2265,7 +2275,8 @@ static int read_noendbr_hints(struct objtool_file *file)
return 0;

for_each_reloc(rsec, reloc) {
- insn = find_insn(file, reloc->sym->sec, reloc->sym->offset + reloc->addend);
+ insn = find_insn(file, reloc->sym->sec,
+ reloc->sym->offset + reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.noendbr entry");
return -1;
@@ -2293,7 +2304,7 @@ static int read_retpoline_hints(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.retpoline_safe entry");
return -1;
@@ -2329,7 +2340,7 @@ static int read_instr_hints(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.instr_end entry");
return -1;
@@ -2348,7 +2359,7 @@ static int read_instr_hints(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.instr_begin entry");
return -1;
@@ -2376,7 +2387,7 @@ static int read_validate_unret_hints(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.instr_end entry");
return -1;
@@ -2407,7 +2418,7 @@ static int read_intra_function_calls(struct objtool_file *file)
return -1;
}

- insn = find_insn(file, reloc->sym->sec, reloc->addend);
+ insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
if (!insn) {
WARN("bad .discard.intra_function_call entry");
return -1;
@@ -3307,7 +3318,7 @@ static inline const char *call_dest_name(struct instruction *insn)

reloc = insn_reloc(NULL, insn);
if (reloc && !strcmp(reloc->sym->name, "pv_ops")) {
- idx = (reloc->addend / sizeof(void *));
+ idx = (reloc_addend(reloc) / sizeof(void *));
snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx);
return pvname;
}
@@ -3325,7 +3336,7 @@ static bool pv_call_dest(struct objtool_file *file, struct instruction *insn)
if (!reloc || strcmp(reloc->sym->name, "pv_ops"))
return false;

- idx = (arch_dest_reloc_offset(reloc->addend) / sizeof(void *));
+ idx = (arch_dest_reloc_offset(reloc_addend(reloc)) / sizeof(void *));

if (file->pv_ops[idx].clean)
return true;
@@ -4270,9 +4281,9 @@ static int validate_ibt_insn(struct objtool_file *file, struct instruction *insn
off = reloc->sym->offset;
if (reloc_type(reloc) == R_X86_64_PC32 ||
reloc_type(reloc) == R_X86_64_PLT32)
- off += arch_dest_reloc_offset(reloc->addend);
+ off += arch_dest_reloc_offset(reloc_addend(reloc));
else
- off += reloc->addend;
+ off += reloc_addend(reloc);

dest = find_insn(file, reloc->sym->sec, off);
if (!dest)
@@ -4329,7 +4340,7 @@ static int validate_ibt_data_reloc(struct objtool_file *file,
struct instruction *dest;

dest = find_insn(file, reloc->sym->sec,
- reloc->sym->offset + reloc->addend);
+ reloc->sym->offset + reloc_addend(reloc));
if (!dest)
return 0;

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index be9d24dcdf56..16e019a1762c 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -833,10 +833,10 @@ static struct reloc *elf_init_reloc(struct elf *elf, struct section *rsec,

reloc->sec = rsec;
reloc->sym = sym;
- reloc->addend = addend;

reloc->rel.r_offset = offset;
reloc->rel.r_info = GELF_R_INFO(sym->idx, type);
+ reloc->rela.r_addend = addend;

if (elf_write_reloc(elf, reloc))
return NULL;
@@ -911,8 +911,6 @@ static int read_reloc(struct section *rsec, int i, struct reloc *reloc)
return -1;
}

- reloc->addend = rela ? reloc->rela.r_addend : 0;
-
return 0;
}

@@ -1231,12 +1229,10 @@ int elf_write_reloc(struct elf *elf, struct reloc *reloc)
struct section *rsec = reloc->sec;
int ret;

- if (rsec->sh.sh_type == SHT_RELA) {
- reloc->rela.r_addend = reloc->addend;
+ if (rsec->sh.sh_type == SHT_RELA)
ret = gelf_update_rela(rsec->data, reloc_idx(reloc), &reloc->rela);
- } else {
+ else
ret = gelf_update_rel(rsec->data, reloc_idx(reloc), &reloc->rel);
- }

if (!ret) {
WARN_ELF("gelf_update_rela");
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index 41d2149f8bb8..be08b32a93ee 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -75,7 +75,6 @@ struct reloc {
struct section *sec;
struct symbol *sym;
struct list_head sym_reloc_entry;
- s64 addend;
bool jump_table_start;
};

@@ -217,6 +216,11 @@ static inline void set_reloc_type(struct reloc *reloc, int type)
reloc->rel.r_info = GELF_R_INFO(GELF_R_SYM(reloc->rel.r_info), type);
}

+static inline s64 reloc_addend(struct reloc *reloc)
+{
+ return reloc->rela.r_addend;
+}
+
#define for_each_sec(file, sec) \
list_for_each_entry(sec, &file->elf->sections, list)

diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index baa85c31526b..91b1950f5bd8 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -62,7 +62,7 @@ static void reloc_to_sec_off(struct reloc *reloc, struct section **sec,
unsigned long *off)
{
*sec = reloc->sym->sec;
- *off = reloc->sym->offset + reloc->addend;
+ *off = reloc->sym->offset + reloc_addend(reloc);
}

static int get_alt_entry(struct elf *elf, const struct special_entry *entry,
@@ -126,7 +126,7 @@ static int get_alt_entry(struct elf *elf, const struct special_entry *entry,
sec, offset + entry->key);
return -1;
}
- alt->key_addend = key_reloc->addend;
+ alt->key_addend = reloc_addend(key_reloc);
}

return 0;
--
2.40.1