Re: [PATCH] objtool: Move objtool_file struct off the stack

[moosotc]

Josh Poimboeuf <jpoimboe@xxxxxxxxxx> writes:

> Objtool uses over 512k of stack, thanks to the hash table embedded in
> the objtool_file struct.  This causes an unnecessarily large stack
> allocation and breaks users with low stack limits.
>
> Move the struct off the stack.
>
> Fixes: 042ba73fe7eb ("objtool: Add several performance improvements")
> Reported-by: Vassili Karpov <moosotc@xxxxxxxxx>
> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> ---
>  tools/objtool/check.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/objtool/check.c b/tools/objtool/check.c
> index 0414a0d52262..91c4799192e1 100644
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -2184,9 +2184,10 @@ static void cleanup(struct objtool_file *file)
>  	elf_close(file->elf);
>  }
>  
> +struct objtool_file file;
> +

Maybe it also deserves a "static" storage duration (if nothing else this
would prevent possible name clashes)?

>  int check(const char *_objname, bool orc)
>  {
> -	struct objtool_file file;
>  	int ret, warnings = 0;
>  
>  	objname = _objname;

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