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 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 DB6A0C77B75 for ; Tue, 16 May 2023 08:44:34 +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:Message-ID:Date:References :In-Reply-To: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=M31NpMZEWlB1tJubQ9gDYi6VDpS2XAWqMycEOgw4z0o=; b=d8Nm+jmvK6xyd3 5MVm3pAWfranJZ5T/+1xzYj/as1o3sYDOIfSXWtqfXTfqlczNaM44Cg8vjDFuz8wFGaS+1Ob4VlAI otR8J67QbFz9p3iqAQAjNKejtGZShewdjL/oWjl5QlxSXobh11SECcUTWrzrQ+GXeLq9q6/PF2cNi 3Y5mZ8fbh9IW+etDa+8DydeReZefqPNeINopKTR7aAMsG+H628AD4nMADMMaqrMcV7Vp7NnRvLifE sb863+AN0N/fMZkjLr9sfb0wf3psGv48qNEDdbyQexpTRl+9QwESIiM9nspybwHte2qlG81op/blo StAunV4rx2bcvN3c4TUQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pyqI0-004tyR-0h; Tue, 16 May 2023 08:44:12 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pyqHx-004txD-1H for linux-arm-kernel@lists.infradead.org; Tue, 16 May 2023 08:44:10 +0000 From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1684226647; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=n2M+9ZjTzGPpNEj89SkqrnJtVEb8EvbjHFOGwlS/Hlc=; b=taEdn4WIm5bBlZx1dsENbpxFU7hSIW/QN/Tq7OpYBIKyAsqsdi6oYMKOspZzhM0nE1vkB6 fxfTRS1596hW9a3KQU6CEoVmzntnz3HxSg7AB19MSq7HXapKQqEQ5UZqhjjC8FW65QXGxt LzZKx/Ke1IwoB45LiH9eSp6xR+YcCvE/6hYCWZRxgPtWT+nW0/p7YOI1yFlauCen5yjBsw 6rREP19ov1r9Ijlwq8hHokQ1FDboJfpjBhMAp7pRM+u9tmvIsiKu+EY3C8fH9lm48495ym SNLG8rvprpmLiIxBTsAZ/g5uo2tZda7NqvDI0TWG8efaen8d2uSRRV4UTaLIpw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1684226647; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=n2M+9ZjTzGPpNEj89SkqrnJtVEb8EvbjHFOGwlS/Hlc=; b=uBHbcQ+EM/2f1WC9i1Bn9WYA5fJMvZEk0SVfbq0tDVlLVt1X2RHjbYo4pIOB8cTvn/iZgC O0tVSf+RKw6CnvAg== To: "Russell King (Oracle)" Cc: Andrew Morton , linux-mm@kvack.org, Christoph Hellwig , Uladzislau Rezki , Lorenzo Stoakes , Peter Zijlstra , Baoquan He , John Ogness , linux-arm-kernel@lists.infradead.org, Mark Rutland , Marc Zyngier , x86@kernel.org Subject: Re: Excessive TLB flush ranges In-Reply-To: References: <87a5y5a6kj.ffs@tglx> <87353x9y3l.ffs@tglx> <87zg658fla.ffs@tglx> <87r0rg93z5.ffs@tglx> Date: Tue, 16 May 2023 10:44:07 +0200 Message-ID: <87cz308y3s.ffs@tglx> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230516_014409_574798_B754F125 X-CRM114-Status: GOOD ( 11.22 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, May 16 2023 at 09:19, Russell King wrote: > On Tue, May 16, 2023 at 08:37:18AM +0200, Thomas Gleixner wrote: >> void flush_tlb_kernel_vas(struct list_head *list, unsigned int num_entries): >> >> So that an architecture can decide whether it's worth to do walk the >> entries or whether it resorts to a flush all. > > Is "num_entries" what an arch would want to use? How would it use that? > It doesn't tell an arch whether there is a large range of many list > entries, or a single entry covering a large range. Does it matter? The total number of entries to flush is what accumulates and at some architecture specific threshold that becomes more expensive than a full flush, independent of the range of the individual list entries, no? Thanks, tglx _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel