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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 97B8EC432C3 for ; Thu, 14 Nov 2019 09:52:21 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 543AD2063A for ; Thu, 14 Nov 2019 09:52:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 543AD2063A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47DGwz0CvnzF4g0 for ; Thu, 14 Nov 2019 20:52:19 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 47DFxr1DqDzF5ZV for ; Thu, 14 Nov 2019 20:08:00 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 47DFxq68zfz9sRR; Thu, 14 Nov 2019 20:07:59 +1100 (AEDT) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: a42d6ba8c5be5aa597d25dbc15e336a2eca40260 In-Reply-To: <20191024075801.22434-1-aneesh.kumar@linux.ibm.com> To: "Aneesh Kumar K.V" , npiggin@gmail.com, paulus@samba.org From: Michael Ellerman Subject: Re: [PATCH v1 1/3] mm/powerpc/book3s64/radix: Remove unused code. Message-Id: <47DFxq68zfz9sRR@ozlabs.org> Date: Thu, 14 Nov 2019 20:07:59 +1100 (AEDT) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Aneesh Kumar K.V" , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, 2019-10-24 at 07:57:59 UTC, "Aneesh Kumar K.V" wrote: > mm_tlb_flush_nested change was added in the mmu gather tlb flush to handle > the case of parallel pte invalidate happening with mmap_sem held in read > mode. This fix was done by commit: 02390f66bd23 ("powerpc/64s/radix: Fix > MADV_[FREE|DONTNEED] TLB flush miss problem with THP") and the problem is > explained in detail in commit: 99baac21e458 ("mm: fix MADV_[FREE|DONTNEED] TLB > flush miss problem") > > This was later updated by commit: 7a30df49f63a ("mm: mmu_gather: remove > __tlb_reset_range() for force flush") to do a full mm flush rather than > a range flush. By commit: dd2283f2605e ("mm: mmap: zap pages with read mmap_sem > in munmap") we are also now allowing a page table free in mmap_sem read mode > which means we should do a PWC flush too. Our current full mm flush imply > a PWC flush. > > With all the above change the mm_tlb_flush_nested(mm) branch in radix__tlb_flush > will never be taken because for the nested case we would have taken the > if (tlb->fullmm) branch. This patch removes the unused code. Also, remove the > gflush change in __radix__flush_tlb_range that was added to handle the range tlb > flush code. We only check for THP there because hugetlb is flushed via a > different code path where page size is explicitly specified > > This is a partial revert of commit: 02390f66bd23 ("powerpc/64s/radix: Fix > MADV_[FREE|DONTNEED] TLB flush miss problem with THP") > > Signed-off-by: Aneesh Kumar K.V Series applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/a42d6ba8c5be5aa597d25dbc15e336a2eca40260 cheers