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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 E40A3C07542 for ; Mon, 27 May 2019 09:24:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC6592173B for ; Mon, 27 May 2019 09:24:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="JiFX2riS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726326AbfE0JYy (ORCPT ); Mon, 27 May 2019 05:24:54 -0400 Received: from merlin.infradead.org ([205.233.59.134]:37652 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725996AbfE0JYy (ORCPT ); Mon, 27 May 2019 05:24:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=22VCUVWFQ70wC/rGVrsL4tsiR5MgN5GSByLf7q0pVG8=; b=JiFX2riSgBH8/l1M0aQbcj+x3 Yi33Kac7TaofrwjlYxdjgqyD2RCx/SIo1qJP/GTAIcLoCRnFf/8Mln3rdQgmBJ0Hk6evV96k93MmQ AyX+Jd9jyVqVORnh9GNJDRFFCC9rXIB9XUBs8qpLg068juD4luQqwglo2O+lWgD0L8O0XWUxDvMtM viRG3/o/MsMkqeGSLjaYwynorXv2uMx+8uivzTQLmcBfG10gX/r0YlTjJNYQRepzTlXPHYxiZw1WB rIsk6jkSsBYReL0lvHf/2JnPJuTFZGahCb4TUz/ZzDbipzw7T74u9lsUuV4mTBxVtOsMAR2KVM60d ncLWXayLA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hVBrw-0001n9-7D; Mon, 27 May 2019 09:24:36 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id AC7BF20137ADA; Mon, 27 May 2019 11:24:34 +0200 (CEST) Date: Mon, 27 May 2019 11:24:34 +0200 From: Peter Zijlstra To: Nadav Amit Cc: Ingo Molnar , Andy Lutomirski , Borislav Petkov , linux-kernel@vger.kernel.org, Dave Hansen , Thomas Gleixner , "H. Peter Anvin" , x86@kernel.org Subject: Re: [RFC PATCH 4/6] x86/mm/tlb: Refactor common code into flush_tlb_on_cpus() Message-ID: <20190527092434.GT2623@hirez.programming.kicks-ass.net> References: <20190525082203.6531-1-namit@vmware.com> <20190525082203.6531-5-namit@vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190525082203.6531-5-namit@vmware.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, May 25, 2019 at 01:22:01AM -0700, Nadav Amit wrote: > There is one functional change, which should not affect correctness: > flush_tlb_mm_range compared loaded_mm and the mm to figure out if local > flush is needed. Instead, the common code would look at the mm_cpumask() > which should give the same result. > @@ -786,18 +804,9 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, > info = get_flush_tlb_info(mm, start, end, stride_shift, freed_tables, > new_tlb_gen); > > - if (mm == this_cpu_read(cpu_tlbstate.loaded_mm)) { > - lockdep_assert_irqs_enabled(); > - local_irq_disable(); > - flush_tlb_func_local(info, TLB_LOCAL_MM_SHOOTDOWN); > - local_irq_enable(); > - } > - > - if (cpumask_any_but(mm_cpumask(mm), cpu) < nr_cpu_ids) > - flush_tlb_others(mm_cpumask(mm), info); So if we want to double check that; we'd add: WARN_ON_ONCE(cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)) == (mm == this_cpu_read(cpu_tlbstate.loaded_mm))); right? > + flush_tlb_on_cpus(mm_cpumask(mm), info); > > put_flush_tlb_info(); > - put_cpu(); > }