From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3668C3D0C4 for ; Tue, 2 Apr 2024 07:53:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712044404; cv=none; b=PmD/vdfhUImb4y/fNrdhe9qUVj8uKODx8p2v1wc5nqO+Wd312TlsY04l3cOHYOeJM4RkQdndQu9pvMPFBNEMmFcLG4huF/xa5Jj+AfaOGyv9DxjbZlVabKiqrWG0HPcIhb77nQ5k/9Dugvfpy3t1onlcH+Yh9j4RIgSrIy9SeBQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712044404; c=relaxed/simple; bh=ztExGHyh4rH9+6267FI7141vunmEWg+m1+gxQbT5pns=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mCCrzOOygEzQcoPsfIF1l+DQ8GdQbIpXgneN9F/MLwVOZokc+X0aRT0h8ADwxIGLGXVF5yMhub2uULgPUVjuf1wAjcpXYiFsXIorZwry06Tc3IFvFG+ywnnQHRXld1VToNgFmJK57qH21AXY4NRJne3MJGwKfiSokzGwQ3FyGpY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4V80Tk2SWLzbds4; Tue, 2 Apr 2024 15:52:26 +0800 (CST) Received: from dggpemm100001.china.huawei.com (unknown [7.185.36.93]) by mail.maildlp.com (Postfix) with ESMTPS id CD95B18007B; Tue, 2 Apr 2024 15:53:20 +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; Tue, 2 Apr 2024 15:53:19 +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 6/7] s390: mm: accelerate pagefault when badaccess Date: Tue, 2 Apr 2024 15:51:41 +0800 Message-ID: <20240402075142.196265-7-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20240402075142.196265-1-wangkefeng.wang@huawei.com> References: <20240402075142.196265-1-wangkefeng.wang@huawei.com> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm100001.china.huawei.com (7.185.36.93) The vm_flags of vma already checked under per-VMA lock, if it is a bad access, directly handle error and return, there is no need to lock_mm_and_find_vma() and check vm_flags again. Signed-off-by: Kefeng Wang --- arch/s390/mm/fault.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index c421dd44ffbe..162ca2576fd4 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -325,7 +325,8 @@ static void do_exception(struct pt_regs *regs, int access) goto lock_mmap; if (!(vma->vm_flags & access)) { vma_end_read(vma); - goto lock_mmap; + count_vm_vma_lock_event(VMA_LOCK_SUCCESS); + return handle_fault_error_nolock(regs, SEGV_ACCERR); } fault = handle_mm_fault(vma, address, flags | FAULT_FLAG_VMA_LOCK, regs); if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) -- 2.27.0