From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C52DBC433F5 for ; Mon, 23 May 2022 14:52:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237313AbiEWOwH (ORCPT ); Mon, 23 May 2022 10:52:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52892 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237284AbiEWOwB (ORCPT ); Mon, 23 May 2022 10:52:01 -0400 Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B2A728E0E for ; Mon, 23 May 2022 07:51:58 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1653317516; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=PDuBGpkT9ArerlP1XBDcRGRfZ28TAQhMJtn5mwFKc7M=; b=pT6NCGz1IFsXBIrDvwCoik1ZV8eldYrPZNWLkNKH+lo2SU9YYNuxj+hKHhZzXVUuMbNE7n ZF4FDr2WOm/hifRLWsWleJR17juhKvG0QhW1QsaM8mahfr7jYAM/cXWMiE1g2eigcue0lZ MzJ4QmeUBjvLQqZBs4OSwm+Y//LCyxU= From: andrey.konovalov@linux.dev To: Will Deacon , Catalin Marinas Cc: Andrey Konovalov , Marco Elver , Alexander Potapenko , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Vincenzo Frascino , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH v2 2/2] arm64: stacktrace: use non-atomic __set_bit Date: Mon, 23 May 2022 16:51:52 +0200 Message-Id: <23dfa36d1cc91e4a1059945b7834eac22fb9854d.1653317461.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrey Konovalov Use the non-atomic version of set_bit() in arch/arm64/kernel/stacktrace.c, as there is no concurrent accesses to frame->prev_type. This speeds up stack trace collection and improves the boot time of Generic KASAN by 2-5%. Suggested-by: Mark Rutland Acked-by: Mark Rutland Signed-off-by: Andrey Konovalov --- arch/arm64/kernel/stacktrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index 33e96ae4b15f..03593d451b0a 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -103,7 +103,7 @@ static int notrace unwind_frame(struct task_struct *tsk, if (fp <= frame->prev_fp) return -EINVAL; } else { - set_bit(frame->prev_type, frame->stacks_done); + __set_bit(frame->prev_type, frame->stacks_done); } /* -- 2.25.1