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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0E30C3A5A2 for ; Mon, 19 Aug 2019 15:10:27 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 7565E20651 for ; Mon, 19 Aug 2019 15:10:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="en26yL6P" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7565E20651 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=XEZ5opWXNs6pDctX1+eEPeIrsCpVkjlbYeNyyQXrT9w=; b=en26yL6PBiubJU lZ4zm7YAag+YWfO5hvyrxwyS98z8ZBvdVbDEaIRsjlFll+SZ2Zok7lhqzjrNKnjwutj23q4xAXYSC uZR8IfhG7hO3I3YoUxtwo5Is1bX81BTEaAEwbwJ1f7psPV57ql4I09K+96wcr66xcfAhQaABmGdMf Ddw4z3MvgBhE8qBX5hwlOvLXGVwwOvEnxkuVXjdyLMXUr3O28dLBdR9wL52w9sNZGW/3rFl/Jkn+b tnPYDl4Vf+pew9NK+CFlGREsXbSqh4EhBbRBkj2axYUP+OQK9jI95eyBL3RCzBDjfSST/2JEan9iy JE70jPLSCp0zs3AMBwZw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hzjId-0002I4-05; Mon, 19 Aug 2019 15:10:23 +0000 Received: from hch by bombadil.infradead.org with local (Exim 4.92 #3 (Red Hat Linux)) id 1hzjIX-0002Hg-IY; Mon, 19 Aug 2019 15:10:17 +0000 Date: Mon, 19 Aug 2019 08:10:17 -0700 From: "hch@infradead.org" To: Anup Patel Subject: Re: [PATCH] RISC-V: Issue a local tlb flush if possible. Message-ID: <20190819151015.GA3316@infradead.org> References: <20190810014309.20838-1-atish.patra@wdc.com> <20190812145631.GC26897@infradead.org> <20190813143027.GA31668@infradead.org> <3f55d5878044129a3cbb72b13b712e9a1c218dc7.camel@wdc.com> <20190819144627.GA27061@infradead.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.4 (2019-03-13) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "aou@eecs.berkeley.edu" , "alexios.zavras@intel.com" , "gregkh@linuxfoundation.org" , Anup Patel , "linux-kernel@vger.kernel.org" , "hch@infradead.org" , Atish Patra , "palmer@sifive.com" , "paul.walmsley@sifive.com" , "linux-riscv@lists.infradead.org" , "allison@lohutok.net" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+infradead-linux-riscv=archiver.kernel.org@lists.infradead.org On Mon, Aug 19, 2019 at 08:39:02PM +0530, Anup Patel wrote: > If we were using ASID then yes we don't need to flush anything > but currently we don't use ASID due to lack of HW support and > HW can certainly do speculatively page table walks so flushing > local TLB when MM mask is empty might help. > > This just my theory and we need to stress test more. Well, when we context switch away from a mm we always flush the local tlb. So either the mm_struct has never been scheduled in, or we alrady did a local_tlb_flush and we context switched it up. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv