#include <string.h>
#include <stdlib.h>
+#include <sys/mman.h>
#include "builtin.h"
#include "cfi.h"
bool skip_orig;
};
-struct cfi_init_state initial_func_cfi;
+static unsigned long nr_cfi, nr_cfi_reused, nr_cfi_cache;
+
+static struct cfi_init_state initial_func_cfi;
+static struct cfi_state init_cfi;
+static struct cfi_state func_cfi;
struct instruction *find_insn(struct objtool_file *file,
struct section *sec, unsigned long offset)
state->noinstr = sec->noinstr;
}
+static struct cfi_state *cfi_alloc(void)
+{
+ struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
+ if (!cfi) {
+ WARN("calloc failed");
+ exit(1);
+ }
+ nr_cfi++;
+ return cfi;
+}
+
+static int cfi_bits;
+static struct hlist_head *cfi_hash;
+
+static inline bool cficmp(struct cfi_state *cfi1, struct cfi_state *cfi2)
+{
+ return memcmp((void *)cfi1 + sizeof(cfi1->hash),
+ (void *)cfi2 + sizeof(cfi2->hash),
+ sizeof(struct cfi_state) - sizeof(struct hlist_node));
+}
+
+static inline u32 cfi_key(struct cfi_state *cfi)
+{
+ return jhash((void *)cfi + sizeof(cfi->hash),
+ sizeof(*cfi) - sizeof(cfi->hash), 0);
+}
+
+static struct cfi_state *cfi_hash_find_or_add(struct cfi_state *cfi)
+{
+ struct hlist_head *head = &cfi_hash[hash_min(cfi_key(cfi), cfi_bits)];
+ struct cfi_state *obj;
+
+ hlist_for_each_entry(obj, head, hash) {
+ if (!cficmp(cfi, obj)) {
+ nr_cfi_cache++;
+ return obj;
+ }
+ }
+
+ obj = cfi_alloc();
+ *obj = *cfi;
+ hlist_add_head(&obj->hash, head);
+
+ return obj;
+}
+
+static void cfi_hash_add(struct cfi_state *cfi)
+{
+ struct hlist_head *head = &cfi_hash[hash_min(cfi_key(cfi), cfi_bits)];
+
+ hlist_add_head(&cfi->hash, head);
+}
+
+static void *cfi_hash_alloc(void)
+{
+ cfi_bits = vmlinux ? ELF_HASH_BITS - 3 : 13;
+ cfi_hash = mmap(NULL, sizeof(struct hlist_head) << cfi_bits,
+ PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANON, -1, 0);
+ if (cfi_hash == (void *)-1L) {
+ WARN("mmap fail cfi_hash");
+ cfi_hash = NULL;
+ } else if (stats) {
+ printf("cfi_bits: %d\n", cfi_bits);
+ }
+
+ return cfi_hash;
+}
+
+static unsigned long nr_insns;
+static unsigned long nr_insns_visited;
+
/*
* Call the arch-specific instruction decoder for all the instructions and add
* them to the global instruction list.
struct symbol *func;
unsigned long offset;
struct instruction *insn;
- unsigned long nr_insns = 0;
int ret;
for_each_sec(file, sec) {
memset(insn, 0, sizeof(*insn));
INIT_LIST_HEAD(&insn->alts);
INIT_LIST_HEAD(&insn->stack_ops);
- init_cfi_state(&insn->cfi);
insn->sec = sec;
insn->offset = offset;
memset(nop, 0, sizeof(*nop));
INIT_LIST_HEAD(&nop->alts);
INIT_LIST_HEAD(&nop->stack_ops);
- init_cfi_state(&nop->cfi);
nop->sec = special_alt->new_sec;
nop->offset = special_alt->new_off + special_alt->new_len;
static int read_unwind_hints(struct objtool_file *file)
{
+ struct cfi_state cfi = init_cfi;
struct section *sec, *relocsec;
- struct reloc *reloc;
struct unwind_hint *hint;
struct instruction *insn;
+ struct reloc *reloc;
int i;
sec = find_section_by_name(file->elf, ".discard.unwind_hints");
insn->hint = true;
if (hint->type == UNWIND_HINT_TYPE_FUNC) {
- set_func_state(&insn->cfi);
+ insn->cfi = &func_cfi;
continue;
}
- if (arch_decode_hint_reg(insn, hint->sp_reg)) {
+ if (insn->cfi)
+ cfi = *(insn->cfi);
+
+ if (arch_decode_hint_reg(hint->sp_reg, &cfi.cfa.base)) {
WARN_FUNC("unsupported unwind_hint sp base reg %d",
insn->sec, insn->offset, hint->sp_reg);
return -1;
}
- insn->cfi.cfa.offset = hint->sp_offset;
- insn->cfi.type = hint->type;
- insn->cfi.end = hint->end;
+ cfi.cfa.offset = hint->sp_offset;
+ cfi.type = hint->type;
+ cfi.end = hint->end;
+
+ insn->cfi = cfi_hash_find_or_add(&cfi);
}
return 0;
if (!insn->alt_group)
return 0;
+ if (!insn->cfi) {
+ WARN("CFI missing");
+ return -1;
+ }
+
alt_cfi = insn->alt_group->cfi;
group_off = insn->offset - insn->alt_group->first_insn->offset;
if (!alt_cfi[group_off]) {
- alt_cfi[group_off] = &insn->cfi;
+ alt_cfi[group_off] = insn->cfi;
} else {
- if (memcmp(alt_cfi[group_off], &insn->cfi, sizeof(struct cfi_state))) {
+ if (cficmp(alt_cfi[group_off], insn->cfi)) {
WARN_FUNC("stack layout conflict in alternatives",
insn->sec, insn->offset);
return -1;
static bool insn_cfi_match(struct instruction *insn, struct cfi_state *cfi2)
{
- struct cfi_state *cfi1 = &insn->cfi;
+ struct cfi_state *cfi1 = insn->cfi;
int i;
+ if (!cfi1) {
+ WARN("CFI missing");
+ return false;
+ }
+
if (memcmp(&cfi1->cfa, &cfi2->cfa, sizeof(cfi1->cfa))) {
WARN_FUNC("stack state mismatch: cfa1=%d%+d cfa2=%d%+d",
struct instruction *insn, struct insn_state state)
{
struct alternative *alt;
- struct instruction *next_insn;
+ struct instruction *next_insn, *prev_insn = NULL;
struct section *sec;
u8 visited;
int ret;
if (insn->visited & visited)
return 0;
+ } else {
+ nr_insns_visited++;
}
if (state.noinstr)
state.instr += insn->instr;
- if (insn->hint)
- state.cfi = insn->cfi;
- else
- insn->cfi = state.cfi;
+ if (insn->hint) {
+ state.cfi = *insn->cfi;
+ } else {
+ /* XXX track if we actually changed state.cfi */
+
+ if (prev_insn && !cficmp(prev_insn->cfi, &state.cfi)) {
+ insn->cfi = prev_insn->cfi;
+ nr_cfi_reused++;
+ } else {
+ insn->cfi = cfi_hash_find_or_add(&state.cfi);
+ }
+ }
insn->visited |= visited;
return 1;
}
+ prev_insn = insn;
insn = next_insn;
}
int ret, warnings = 0;
arch_initial_func_cfi_state(&initial_func_cfi);
+ init_cfi_state(&init_cfi);
+ init_cfi_state(&func_cfi);
+ set_func_state(&func_cfi);
+
+ if (!cfi_hash_alloc())
+ goto out;
+
+ cfi_hash_add(&init_cfi);
+ cfi_hash_add(&func_cfi);
ret = decode_sections(file);
if (ret < 0)
goto out;
+
warnings += ret;
if (list_empty(&file->insn_list))
goto out;
warnings += ret;
+ if (stats) {
+ printf("nr_insns_visited: %ld\n", nr_insns_visited);
+ printf("nr_cfi: %ld\n", nr_cfi);
+ printf("nr_cfi_reused: %ld\n", nr_cfi_reused);
+ printf("nr_cfi_cache: %ld\n", nr_cfi_cache);
+ }
+
out:
/*
* For now, don't fail the kernel build on fatal warnings. These
projects / users / dwmw2 / linux.git / commitdiff