From patchwork Tue May 19 17:54:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 11558293 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E064113B1 for ; Tue, 19 May 2020 18:01:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9D1520873 for ; Tue, 19 May 2020 18:01:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="SVXeb2Ob" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728264AbgESSBu (ORCPT ); Tue, 19 May 2020 14:01:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33388 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727066AbgESSBu (ORCPT ); Tue, 19 May 2020 14:01:50 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA772C08C5C3 for ; Tue, 19 May 2020 11:01:48 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id s8so379422wrt.9 for ; Tue, 19 May 2020 11:01:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=wblWsf3gxbDp6PSj/ehcYDd+oP1x7SYe4Bh2SWvMsGw=; b=SVXeb2Ob4Qkst7O5mL6UJ2iL9TD8FeQw9vSwN576mogif6BcdDk/DVx3V2M7dI6n21 cDlB4PgyVw/zWEvawRrLAkk8d7OsM7cAfcUCgb++qPIGOWWFGKIqdCOmLwUmcPpIc1DM nP4/NYwjGzU0cZQa1VFg9eXlqA5QFsvshmZ8mLhFDLun84zEb+yVsdQt288r7v2A6o14 TEfy1o2q/7e8nwZFntyVfD0p19BG2lWIz/U0rwseBJSSfNFTvIJaoIbYbNDXz+jUT31H RPGF0E7utbNt/zM+SiQI1i5jIw+y8XFEsPo89fPClJIpEvylAxB4p0fHyzmt/juXQ9nx X/5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=wblWsf3gxbDp6PSj/ehcYDd+oP1x7SYe4Bh2SWvMsGw=; b=TZyeo0XY+syR2EIS9yNpn4daOeA1CgP/EYllpucfiv5iR9sHA26AwX6cuUOEbfHjZt GHwXgktVm+SJgMpqsjJDzPkxz5k6fRsm5zgM4fZDoxsPX7imLErPHgGCqTW3JlfU3eaG btW76vqayJpeeZ8EOnZIqRSNyalQPS0Lp5EV6BoNiJ9zmZLUup3Gmgk4lPGZemO/D3di h6+7nlJNPnwUVBQuUIyRgAHNS/OgFbb2/no+L3tbRRZaqKMF9NvAj4xtK8wSgdwDZBEN Qnr4a8dt/+gbht0xF/YCZC9c8kwJW5kaUkNZwEvdX/TjKAiFttDQGoTWFQpMqGfWAixi NV3A== X-Gm-Message-State: AOAM531GF/v/Zy47nO83u9z4IUiCX7yzmosHXRxY0WOGMCZYT5BCq1jT SxVZ3wlJbZ/RwlcstULz67gYgw== X-Google-Smtp-Source: ABdhPJwQ7epxyLS6UnZ7f06nlDOMCJUnPMBSTjmWHDJI9x8Mwvumsd4wHmMVikP6f8C+lMs+dd9rLA== X-Received: by 2002:a5d:6108:: with SMTP id v8mr107787wrt.286.1589911307392; Tue, 19 May 2020 11:01:47 -0700 (PDT) Received: from localhost.localdomain ([2001:171b:226e:c200:c43b:ef78:d083:b355]) by smtp.gmail.com with ESMTPSA id 1sm510496wmz.13.2020.05.19.11.01.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 May 2020 11:01:46 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-mm@kvack.org Cc: joro@8bytes.org, catalin.marinas@arm.com, will@kernel.org, robin.murphy@arm.com, kevin.tian@intel.com, baolu.lu@linux.intel.com, Jonathan.Cameron@huawei.com, jacob.jun.pan@linux.intel.com, christian.koenig@amd.com, felix.kuehling@amd.com, zhangfei.gao@linaro.org, jgg@ziepe.ca, xuzaibo@huawei.com, fenghua.yu@intel.com, hch@infradead.org, Jean-Philippe Brucker Subject: [PATCH v7 05/24] arm64: mm: Add asid_gen_match() helper Date: Tue, 19 May 2020 19:54:43 +0200 Message-Id: <20200519175502.2504091-6-jean-philippe@linaro.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200519175502.2504091-1-jean-philippe@linaro.org> References: <20200519175502.2504091-1-jean-philippe@linaro.org> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add a macro to check if an ASID is from the current generation, since a subsequent patch will introduce a third user for this test. Signed-off-by: Jean-Philippe Brucker --- arch/arm64/mm/context.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index 9b26f9a88724..d702d60e64da 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -92,6 +92,9 @@ static void set_reserved_asid_bits(void) bitmap_clear(asid_map, 0, NUM_USER_ASIDS); } +#define asid_gen_match(asid) \ + (!(((asid) ^ atomic64_read(&asid_generation)) >> asid_bits)) + static void flush_context(void) { int i; @@ -220,8 +223,7 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) * because atomic RmWs are totally ordered for a given location. */ old_active_asid = atomic64_read(&per_cpu(active_asids, cpu)); - if (old_active_asid && - !((asid ^ atomic64_read(&asid_generation)) >> asid_bits) && + if (old_active_asid && asid_gen_match(asid) && atomic64_cmpxchg_relaxed(&per_cpu(active_asids, cpu), old_active_asid, asid)) goto switch_mm_fastpath; @@ -229,7 +231,7 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) raw_spin_lock_irqsave(&cpu_asid_lock, flags); /* Check that our ASID belongs to the current generation. */ asid = atomic64_read(&mm->context.id); - if ((asid ^ atomic64_read(&asid_generation)) >> asid_bits) { + if (!asid_gen_match(asid)) { asid = new_context(mm); atomic64_set(&mm->context.id, asid); }