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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 289E1C433FE for ; Fri, 30 Sep 2022 14:48:20 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B0F8B6B0072; Fri, 30 Sep 2022 10:48:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AC0526B0073; Fri, 30 Sep 2022 10:48:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9607D6B0074; Fri, 30 Sep 2022 10:48:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 858446B0072 for ; Fri, 30 Sep 2022 10:48:19 -0400 (EDT) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 4039181487 for ; Fri, 30 Sep 2022 14:48:19 +0000 (UTC) X-FDA: 79969032318.11.EF39686 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by imf28.hostedemail.com (Postfix) with ESMTP id 26A7EC0012 for ; Fri, 30 Sep 2022 14:48:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1664549298; x=1696085298; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=sExrmnnOGqgb/icKqEgn6j12KzbzBwzl0nhEtIquc4M=; b=nJ/rlp04N/kg+D9/kNgg+hF57Mk9fahzu15DXOGzQfYrgPgv5URPIsEj nqPB/eB0LibaaGnYg6qALBvUOalyIsC09wwmSyNLEK43cp9/+tkFtHwW+ hKh3sVf7r9VM32sefZCH9Apf4wMDR8eRp44DOotm4oRd7Sn3mHzGLI/qj PRN8fkL3MqnsT6CoM61QkAw2anquL8CQurMOuihbic6XvkT0t+mEDgUCQ 8SlzhiK58uCP7TVOO1Vtd8OMp6RR9AfezKHzSkbf9aWB2naWo4oZPD+R9 Xw2yUCSYdpAkqIegs6vRiHolhn19FcDgC3PpmsXmECnXT8zpmFfVAiWnz w==; X-IronPort-AV: E=McAfee;i="6500,9779,10486"; a="299808865" X-IronPort-AV: E=Sophos;i="5.93,358,1654585200"; d="scan'208";a="299808865" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2022 07:48:16 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10486"; a="653563756" X-IronPort-AV: E=Sophos;i="5.93,358,1654585200"; d="scan'208";a="653563756" Received: from herrerop-mobl1.ger.corp.intel.com (HELO box.shutemov.name) ([10.252.38.128]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Sep 2022 07:48:11 -0700 Received: by box.shutemov.name (Postfix, from userid 1000) id 7776A104D62; Fri, 30 Sep 2022 17:48:02 +0300 (+03) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Kostya Serebryany , Andrey Ryabinin , Andrey Konovalov , Alexander Potapenko , Taras Madan , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , Bharata B Rao , Jacob Pan , Ashok Raj , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv9 08/14] x86/mm: Reduce untagged_addr() overhead until the first LAM user Date: Fri, 30 Sep 2022 17:47:52 +0300 Message-Id: <20220930144758.30232-9-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220930144758.30232-1-kirill.shutemov@linux.intel.com> References: <20220930144758.30232-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b="nJ/rlp04"; spf=none (imf28.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 192.55.52.93) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1664549298; a=rsa-sha256; cv=none; b=VpK4KRGEzjitRK5PDQLYS5vY1O+tHpsEllgYpJ1yXmw0T7J152gICmqAFR0s4wCGS7y/En eg4Ci4yCgWe5Bbn6mV5e7lOhKJnVzhg7OkzhTOtLWetEs+hkHL/s1YZZWXGqzkwQnZvRc4 irCJSH1JFOt+q3vkwI8ua5ZpW8JoD8k= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1664549298; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=182mUYb2xfynMugUeQjzc+2oZJR0xz9IE3wxmtxC6WA=; b=UGwjTGg1cvPLOik/0pM6Yr5j+jCH/D1hDve8AlqQXM7R4VMputghzmiOkRUAOkIEcxJJMo 0E+znN6ieGgXCOq5p+XNdK05KrPRQp0g4uDNV3QcpBfgcBT7o78Iu5Ph2jIgTNTCYDkewS 2rtHm9ln8X1OukH2CuCqyxZpalwzhMA= X-Stat-Signature: uis41t5ik57hdxbz8mfssc6wf4gt9f15 X-Rspamd-Queue-Id: 26A7EC0012 Authentication-Results: imf28.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b="nJ/rlp04"; spf=none (imf28.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 192.55.52.93) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none) X-Rspam-User: X-Rspamd-Server: rspam07 X-HE-Tag: 1664549297-31624 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Use static key to reduce untagged_addr() overhead. The key only gets enabled when the first process enables LAM. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/uaccess.h | 8 ++++++-- arch/x86/kernel/process_64.c | 4 ++++ 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 803241dfc473..fc33d6ba1090 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -22,6 +22,8 @@ static inline bool pagefault_disabled(void); #endif #ifdef CONFIG_X86_64 +DECLARE_STATIC_KEY_FALSE(tagged_addr_key); + /* * Mask out tag bits from the address. * @@ -30,8 +32,10 @@ static inline bool pagefault_disabled(void); */ #define untagged_addr(mm, addr) ({ \ u64 __addr = (__force u64)(addr); \ - s64 sign = (s64)__addr >> 63; \ - __addr &= (mm)->context.untag_mask | sign; \ + if (static_branch_likely(&tagged_addr_key)) { \ + s64 sign = (s64)__addr >> 63; \ + __addr &= (mm)->context.untag_mask | sign; \ + } \ (__force __typeof__(addr))__addr; \ }) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index d75252a5c7be..1730c2fcc7ab 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -742,6 +742,9 @@ static long prctl_map_vdso(const struct vdso_image *image, unsigned long addr) } #endif +DEFINE_STATIC_KEY_FALSE(tagged_addr_key); +EXPORT_SYMBOL_GPL(tagged_addr_key); + static void enable_lam_func(void *mm) { struct mm_struct *loaded_mm = this_cpu_read(cpu_tlbstate.loaded_mm); @@ -791,6 +794,7 @@ static int prctl_enable_tagged_addr(struct mm_struct *mm, unsigned long nr_bits) } on_each_cpu_mask(mm_cpumask(mm), enable_lam_func, mm, true); + static_branch_enable(&tagged_addr_key); out: mmap_write_unlock(mm); return ret; -- 2.35.1