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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15500C46CD2 for ; Tue, 30 Jan 2024 08:41:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9D52A6B0085; Tue, 30 Jan 2024 03:41:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 984CA6B00A2; Tue, 30 Jan 2024 03:41:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 826A66B00A3; Tue, 30 Jan 2024 03:41:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 6F14E6B0085 for ; Tue, 30 Jan 2024 03:41:32 -0500 (EST) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 2F1671A07DA for ; Tue, 30 Jan 2024 08:41:32 +0000 (UTC) X-FDA: 81735333624.26.42D3D9D Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf21.hostedemail.com (Postfix) with ESMTP id 8871C1C0010 for ; Tue, 30 Jan 2024 08:41:30 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=none; spf=pass (imf21.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1706604090; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JEXw1J3D7PteHCwNz4WfWsN2UlBo0fltsKu/qwTJH7g=; b=Qci3mYznNqkLggCvgIrQwxiPWmELTnXVYy//wBx5HUSC5MdJS6C40qtOKIoDQ+FrOYcQqL z4tSyI7/wHRmiez3+WYQbnO5H+DoNcKeccJQVNwwFietGQxUBMMODYHsVV3LtmFKv6iRj5 +ScGlyD/JaXJGXJ3XxO8tKYYdKRRmS0= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1706604090; a=rsa-sha256; cv=none; b=foPCIC4SGwaDvavbZ0WdnqfWrzzuTX/Yze32nFUa/iYnTpdiASKLfcLJad4cgwpO060BBR mU/reWaYSvKziStvpyrV8gOAmP/VSMAsddd/CFfQ2euPKXwgmgds7apt3KZIDjCmYdo8jR OToSX3sQPDXRSxEYuaNIB8CGYltdVJ8= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=none; spf=pass (imf21.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com; dmarc=pass (policy=none) header.from=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5232BDA7; Tue, 30 Jan 2024 00:42:13 -0800 (PST) Received: from [10.57.79.54] (unknown [10.57.79.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E241A3F738; Tue, 30 Jan 2024 00:41:25 -0800 (PST) Message-ID: <6cf5cce0-69aa-437b-a13f-4d9adeae01df@arm.com> Date: Tue, 30 Jan 2024 08:41:23 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 5/9] mm/mmu_gather: pass "delay_rmap" instead of encoded page to __tlb_remove_page_size() Content-Language: en-GB To: David Hildenbrand , linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, Andrew Morton , Matthew Wilcox , Catalin Marinas , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Peter Zijlstra , Michael Ellerman , Christophe Leroy , "Naveen N. Rao" , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Arnd Bergmann , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org References: <20240129143221.263763-1-david@redhat.com> <20240129143221.263763-6-david@redhat.com> From: Ryan Roberts In-Reply-To: <20240129143221.263763-6-david@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 8871C1C0010 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: 7anzeqea76484jptc6kryj6xjaemrpsj X-HE-Tag: 1706604090-200213 X-HE-Meta: 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 29/01/2024 14:32, David Hildenbrand wrote: > We have two bits available in the encoded page pointer to store > additional information. Currently, we use one bit to request delay of the > rmap removal until after a TLB flush. > > We want to make use of the remaining bit internally for batching of > multiple pages of the same folio, specifying that the next encoded page > pointer in an array is actually "nr_pages". So pass page + delay_rmap flag > instead of an encoded page, to handle the encoding internally. > > Signed-off-by: David Hildenbrand Reviewed-by: Ryan Roberts > --- > arch/s390/include/asm/tlb.h | 13 ++++++------- > include/asm-generic/tlb.h | 12 ++++++------ > mm/mmu_gather.c | 7 ++++--- > 3 files changed, 16 insertions(+), 16 deletions(-) > > diff --git a/arch/s390/include/asm/tlb.h b/arch/s390/include/asm/tlb.h > index d1455a601adc..48df896d5b79 100644 > --- a/arch/s390/include/asm/tlb.h > +++ b/arch/s390/include/asm/tlb.h > @@ -25,8 +25,7 @@ > void __tlb_remove_table(void *_table); > static inline void tlb_flush(struct mmu_gather *tlb); > static inline bool __tlb_remove_page_size(struct mmu_gather *tlb, > - struct encoded_page *page, > - int page_size); > + struct page *page, bool delay_rmap, int page_size); > > #define tlb_flush tlb_flush > #define pte_free_tlb pte_free_tlb > @@ -42,14 +41,14 @@ static inline bool __tlb_remove_page_size(struct mmu_gather *tlb, > * tlb_ptep_clear_flush. In both flush modes the tlb for a page cache page > * has already been freed, so just do free_page_and_swap_cache. > * > - * s390 doesn't delay rmap removal, so there is nothing encoded in > - * the page pointer. > + * s390 doesn't delay rmap removal. > */ > static inline bool __tlb_remove_page_size(struct mmu_gather *tlb, > - struct encoded_page *page, > - int page_size) > + struct page *page, bool delay_rmap, int page_size) > { > - free_page_and_swap_cache(encoded_page_ptr(page)); > + VM_WARN_ON_ONCE(delay_rmap); > + > + free_page_and_swap_cache(page); > return false; > } > > diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h > index 129a3a759976..2eb7b0d4f5d2 100644 > --- a/include/asm-generic/tlb.h > +++ b/include/asm-generic/tlb.h > @@ -260,9 +260,8 @@ struct mmu_gather_batch { > */ > #define MAX_GATHER_BATCH_COUNT (10000UL/MAX_GATHER_BATCH) > > -extern bool __tlb_remove_page_size(struct mmu_gather *tlb, > - struct encoded_page *page, > - int page_size); > +extern bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, > + bool delay_rmap, int page_size); > > #ifdef CONFIG_SMP > /* > @@ -462,13 +461,14 @@ static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) > static inline void tlb_remove_page_size(struct mmu_gather *tlb, > struct page *page, int page_size) > { > - if (__tlb_remove_page_size(tlb, encode_page(page, 0), page_size)) > + if (__tlb_remove_page_size(tlb, page, false, page_size)) > tlb_flush_mmu(tlb); > } > > -static __always_inline bool __tlb_remove_page(struct mmu_gather *tlb, struct page *page, unsigned int flags) > +static __always_inline bool __tlb_remove_page(struct mmu_gather *tlb, > + struct page *page, bool delay_rmap) > { > - return __tlb_remove_page_size(tlb, encode_page(page, flags), PAGE_SIZE); > + return __tlb_remove_page_size(tlb, page, delay_rmap, PAGE_SIZE); > } > > /* tlb_remove_page > diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c > index 604ddf08affe..ac733d81b112 100644 > --- a/mm/mmu_gather.c > +++ b/mm/mmu_gather.c > @@ -116,7 +116,8 @@ static void tlb_batch_list_free(struct mmu_gather *tlb) > tlb->local.next = NULL; > } > > -bool __tlb_remove_page_size(struct mmu_gather *tlb, struct encoded_page *page, int page_size) > +bool __tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, > + bool delay_rmap, int page_size) > { > struct mmu_gather_batch *batch; > > @@ -131,13 +132,13 @@ bool __tlb_remove_page_size(struct mmu_gather *tlb, struct encoded_page *page, i > * Add the page and check if we are full. If so > * force a flush. > */ > - batch->encoded_pages[batch->nr++] = page; > + batch->encoded_pages[batch->nr++] = encode_page(page, delay_rmap); > if (batch->nr == batch->max) { > if (!tlb_next_batch(tlb)) > return true; > batch = tlb->active; > } > - VM_BUG_ON_PAGE(batch->nr > batch->max, encoded_page_ptr(page)); > + VM_BUG_ON_PAGE(batch->nr > batch->max, page); > > return false; > }