From patchwork Wed Apr 3 08:38:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kefeng Wang X-Patchwork-Id: 13615381 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A3FB4CD1288 for ; Wed, 3 Apr 2024 08:39:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=J2PR35k7EKTz848Vd7Bh/FPnvRXOJgnH4Lnu4OiLaF8=; b=oqxy33OJ4jfpGe fsDdgIhnBPDLjEB9K6Tb1WU2iSDn7bCfD9te1mA0zz6k7QhCYrssnMjLPSEPeuSQKCvwXc5wbHpPO +fuKNkq4M/sad10tJ7Dxa+85qXss73GNlsunwzMWx2M1/FQeI7ETJlaT0fkt09DmZKHJEgZgzCed3 OctobcWdveT/0miqPSeX8qUYQIU843Gg3eXPG8j6/ICCd7ggH7EgG/U2FPiIdsQflqPAjWMKPruTZ 0kuWBOAxBdmKKJ4/QsQXbAKl9QEqFhFf9tywzviouMJZhUzAPlR8GyOAd9879T90NEBd2sZ0EATRp op++IQz0rbdTAy3H062g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrw8t-0000000EwHN-2joQ; Wed, 03 Apr 2024 08:38:47 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrw8r-0000000EwEu-3Mue; Wed, 03 Apr 2024 08:38:45 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:Content-Transfer-Encoding :MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From: Sender:Reply-To:Content-ID:Content-Description; bh=lmVlreGnPFbXRLejlXB9QDif0bxo2zNzlVV4g4MDH8w=; b=PG5v7uzqp2YVt6HPpHEAkydAE0 UnoiCGon9adhmFFe+URNHkUiQmD3gMeR+lHonhKf+nW+FsjalBDvhVJxqtkpG8ggjdtwU4VevtQ4J p3ap8RbQ/HYeME1QaI4xQ/Or1xuxAQGwgruWaH4lkAQN08ODHgbtZB0rVDSX8oKzBeXn3c3IKiwQ0 wAHKdmb1rNW+oHAsxqL3c65/rlWK/fsRIrJ/S9V722b3zICUuaFTVzjlpb7To1Et0k0x4uPNac0qd kbxpDGy0Y1adBv7tqe6ygZWjpG8nTH4OCdPHLX02U2/pjJOKD8zxyywswgwLQ9qZJhD1RjDKEYssK jWWA3mvg==; Received: from szxga06-in.huawei.com ([45.249.212.32]) by desiato.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rrw8n-000000046AS-2jUy; Wed, 03 Apr 2024 08:38:44 +0000 Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4V8dRP0T1xz17MxK; Wed, 3 Apr 2024 16:37:37 +0800 (CST) Received: from dggpemm100001.china.huawei.com (unknown [7.185.36.93]) by mail.maildlp.com (Postfix) with ESMTPS id 67C731A016C; Wed, 3 Apr 2024 16:38:29 +0800 (CST) Received: from localhost.localdomain (10.175.112.125) by dggpemm100001.china.huawei.com (7.185.36.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Wed, 3 Apr 2024 16:38:28 +0800 From: Kefeng Wang To: CC: Russell King , Catalin Marinas , Will Deacon , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexander Gordeev , Gerald Schaefer , Dave Hansen , Andy Lutomirski , Peter Zijlstra , , , , , , , , Kefeng Wang Subject: [PATCH v2 7/7] x86: mm: accelerate pagefault when badaccess Date: Wed, 3 Apr 2024 16:38:05 +0800 Message-ID: <20240403083805.1818160-8-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20240403083805.1818160-1-wangkefeng.wang@huawei.com> References: <20240403083805.1818160-1-wangkefeng.wang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm100001.china.huawei.com (7.185.36.93) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240403_093842_560240_4CF1812E X-CRM114-Status: GOOD ( 13.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The access_error() of vma already checked under per-VMA lock, if it is a bad access, directly handle error, no need to retry with mmap_lock again. In order to release the correct lock, pass the mm_struct into bad_area_access_error(), if mm is NULL, release vma lock, or release mmap_lock. Since the page faut is handled under per-VMA lock, count it as a vma lock event with VMA_LOCK_SUCCESS. Reviewed-by: Suren Baghdasaryan Signed-off-by: Kefeng Wang --- arch/x86/mm/fault.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index a4cc20d0036d..67b18adc75dd 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -866,14 +866,17 @@ bad_area_nosemaphore(struct pt_regs *regs, unsigned long error_code, static void __bad_area(struct pt_regs *regs, unsigned long error_code, - unsigned long address, u32 pkey, int si_code) + unsigned long address, struct mm_struct *mm, + struct vm_area_struct *vma, u32 pkey, int si_code) { - struct mm_struct *mm = current->mm; /* * Something tried to access memory that isn't in our memory map.. * Fix it, but check if it's kernel or user first.. */ - mmap_read_unlock(mm); + if (mm) + mmap_read_unlock(mm); + else + vma_end_read(vma); __bad_area_nosemaphore(regs, error_code, address, pkey, si_code); } @@ -897,7 +900,8 @@ static inline bool bad_area_access_from_pkeys(unsigned long error_code, static noinline void bad_area_access_error(struct pt_regs *regs, unsigned long error_code, - unsigned long address, struct vm_area_struct *vma) + unsigned long address, struct mm_struct *mm, + struct vm_area_struct *vma) { /* * This OSPKE check is not strictly necessary at runtime. @@ -927,9 +931,9 @@ bad_area_access_error(struct pt_regs *regs, unsigned long error_code, */ u32 pkey = vma_pkey(vma); - __bad_area(regs, error_code, address, pkey, SEGV_PKUERR); + __bad_area(regs, error_code, address, mm, vma, pkey, SEGV_PKUERR); } else { - __bad_area(regs, error_code, address, 0, SEGV_ACCERR); + __bad_area(regs, error_code, address, mm, vma, 0, SEGV_ACCERR); } } @@ -1357,8 +1361,9 @@ void do_user_addr_fault(struct pt_regs *regs, goto lock_mmap; if (unlikely(access_error(error_code, vma))) { - vma_end_read(vma); - goto lock_mmap; + bad_area_access_error(regs, error_code, address, NULL, vma); + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + return; } fault = handle_mm_fault(vma, address, flags | FAULT_FLAG_VMA_LOCK, regs); if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) @@ -1394,7 +1399,7 @@ void do_user_addr_fault(struct pt_regs *regs, * we can handle it.. */ if (unlikely(access_error(error_code, vma))) { - bad_area_access_error(regs, error_code, address, vma); + bad_area_access_error(regs, error_code, address, mm, vma); return; }