diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2021-06-24 11:41:01 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2021-09-15 15:51:45 +0200 |
| commit | 8b946cc38e063f0f7bb67789478c38f6d7d457c9 (patch) | |
| tree | 79c8ef923e5195931b09fae2e27a54e913d85237 /tools/objtool/orc_gen.c | |
| parent | b7b205c3a0bc2b51f83cb793178ccbc12addf275 (diff) | |
objtool: Introduce CFI hash
Andi reported that objtool on vmlinux.o consumes more memory than his
system has, leading to horrific performance.
This is in part because we keep a struct instruction for every
instruction in the file in-memory. Shrink struct instruction by
removing the CFI state (which includes full register state) from it
and demand allocating it.
Given most instructions don't actually change CFI state, there's lots
of repetition there, so add a hash table to find previous CFI
instances.
Reduces memory consumption (and runtime) for processing an
x86_64-allyesconfig:
pre: 4:40.84 real, 143.99 user, 44.18 sys, 30624988 mem
post: 2:14.61 real, 108.58 user, 25.04 sys, 16396184 mem
Suggested-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210624095147.756759107@infradead.org
Diffstat (limited to 'tools/objtool/orc_gen.c')
| -rw-r--r-- | tools/objtool/orc_gen.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c index dc9b7dd314b0..ddacb4215748 100644 --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -13,13 +13,19 @@ #include <objtool/warn.h> #include <objtool/endianness.h> -static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi) +static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, + struct instruction *insn) { - struct instruction *insn = container_of(cfi, struct instruction, cfi); struct cfi_reg *bp = &cfi->regs[CFI_BP]; memset(orc, 0, sizeof(*orc)); + if (!cfi) { + orc->end = 0; + orc->sp_reg = ORC_REG_UNDEFINED; + return 0; + } + orc->end = cfi->end; if (cfi->cfa.base == CFI_UNDEFINED) { @@ -162,7 +168,7 @@ int orc_create(struct objtool_file *file) int i; if (!alt_group) { - if (init_orc_entry(&orc, &insn->cfi)) + if (init_orc_entry(&orc, insn->cfi, insn)) return -1; if (!memcmp(&prev_orc, &orc, sizeof(orc))) continue; @@ -186,7 +192,8 @@ int orc_create(struct objtool_file *file) struct cfi_state *cfi = alt_group->cfi[i]; if (!cfi) continue; - if (init_orc_entry(&orc, cfi)) + /* errors are reported on the original insn */ + if (init_orc_entry(&orc, cfi, insn)) return -1; if (!memcmp(&prev_orc, &orc, sizeof(orc))) continue; |