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| 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/arch/x86 | |
| parent | b7b205c3a0bc2b51f83cb793178ccbc12addf275 (diff) | |
| download | linux-8b946cc38e063f0f7bb67789478c38f6d7d457c9.tar.gz linux-8b946cc38e063f0f7bb67789478c38f6d7d457c9.tar.bz2 linux-8b946cc38e063f0f7bb67789478c38f6d7d457c9.zip | |
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/arch/x86')
| -rw-r--r-- | tools/objtool/arch/x86/decode.c | 20 |
1 files changed, 9 insertions, 11 deletions
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index bc821056aba9..3435a32afbd1 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -779,34 +779,32 @@ int arch_rewrite_retpolines(struct objtool_file *file) return 0; } -int arch_decode_hint_reg(struct instruction *insn, u8 sp_reg) +int arch_decode_hint_reg(u8 sp_reg, int *base) { - struct cfi_reg *cfa = &insn->cfi.cfa; - switch (sp_reg) { case ORC_REG_UNDEFINED: - cfa->base = CFI_UNDEFINED; + *base = CFI_UNDEFINED; break; case ORC_REG_SP: - cfa->base = CFI_SP; + *base = CFI_SP; break; case ORC_REG_BP: - cfa->base = CFI_BP; + *base = CFI_BP; break; case ORC_REG_SP_INDIRECT: - cfa->base = CFI_SP_INDIRECT; + *base = CFI_SP_INDIRECT; break; case ORC_REG_R10: - cfa->base = CFI_R10; + *base = CFI_R10; break; case ORC_REG_R13: - cfa->base = CFI_R13; + *base = CFI_R13; break; case ORC_REG_DI: - cfa->base = CFI_DI; + *base = CFI_DI; break; case ORC_REG_DX: - cfa->base = CFI_DX; + *base = CFI_DX; break; default: return -1; |