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From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, mbenes@suse.cz
Subject: Re: [PATCH 1/2] objtool: Optimize re-writing jump_label
Date: Thu, 7 Oct 2021 23:55:50 -0700	[thread overview]
Message-ID: <20211008065550.zge5zkbfrki5osv2@treble> (raw)
In-Reply-To: <20211007212626.950220936@infradead.org>

On Thu, Oct 07, 2021 at 11:22:12PM +0200, Peter Zijlstra wrote:
> There's no point to re-write the jump_label NOP when it's already a NOP.
> 
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> ---
>  tools/objtool/check.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> --- a/tools/objtool/check.c
> +++ b/tools/objtool/check.c
> @@ -1397,7 +1397,7 @@ static int handle_jump_alt(struct objtoo
>  		return -1;
>  	}
>  
> -	if (special_alt->key_addend & 2) {
> +	if ((special_alt->key_addend & 2) && orig_insn->type != INSN_NOP) {
>  		struct reloc *reloc = insn_reloc(file, orig_insn);
>  
>  		if (reloc) {

While you're at it, a comment would be very helpful for that whole
clause.

-- 
Josh


  reply	other threads:[~2021-10-08  6:56 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-07 21:22 [PATCH 0/2] objtool: Avoid pointless modifications Peter Zijlstra
2021-10-07 21:22 ` [PATCH 1/2] objtool: Optimize re-writing jump_label Peter Zijlstra
2021-10-08  6:55   ` Josh Poimboeuf [this message]
2021-10-08 10:03     ` Peter Zijlstra
2021-10-08 16:28       ` Josh Poimboeuf
2021-10-07 21:22 ` [PATCH 2/2] objtool: Optimize/fix retpoline alternative generation Peter Zijlstra
2021-10-08  7:23   ` Josh Poimboeuf
2021-10-08 10:35     ` Peter Zijlstra
2021-10-08 16:39       ` Josh Poimboeuf
2021-10-09 10:42         ` Peter Zijlstra

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