From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [PATCH v2 00/34] Split ptdesc from struct page Date: Thu, 18 May 2023 09:12:04 -0300 Message-ID: References: <20230501192829.17086-1-vishal.moola@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: 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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc: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=4reRZyk/kgy3b4Wjn703ejJ9o7bBBOIOD7FEMRPfZ7E=; b=g/nOb9nebXO2iI ZOsfFaaEyGM3XNngprhGpBeYoIh0/XnoCKyUyoRb0Oinpx7uPcBil6hTkeSxr/qFUB19r9UEy3F6w qQL1i0p9hbRYlHYkMtMN5FMt5OQO9G8t8PWbWMoxSNAAPPrhgi/JCXkcoOBfs0fkZaLLBmuJryNDc wCwoiW0f0pLyBDJcZqt1s8LnHBYpfolZtx+MD6ZbMXziuCD3Yc2FsXtUoebeG+I0V+hYDYFVoYYCU tE8XjJlRibpPCYsLXFQdAQVHRLIEsJ55RYgHmGsMLzRTB4ZmSA52gs5xpm9JbWihykEhDzYtV/zYI 9UP4CdCyzTubjOknlEGg==; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1684411926; x=1687003926; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=b1LVde9eD9hiDa72aXFp01UeitZcx1XKK5VRIQwwJ4w=; b=f1WIjix4LVO2qoUadyymiNEwWX8LVYnKjiZJmHZsA00vpgp8OzN7fLeOXwmxyAsNjQ sHOCKYtaHjUeBnmA70xUS7m11Y8GXRs0HF7i7PVSFcwvUzQVx0yAXlGLYQrw7yq7y3KH MBoMqwZGJTzwuItitFkcFv88cqBCrBWri+DUGp8Fc0eAqXpc1sD7lY1vf9Zu0c1UnHTi g1NSzolGSvoeoheQrwHIwMvc3Rso4DvQpoRRtvFDk7J6iY3SLf6NCCF8S9IRrkOXhhUV HRuCy/CUe+KQ4Lk9dlGX7GSjHNglFJk4MTFkm4joUr1QsJe7so9IrOlgfq/tmei89LyY B2xw== Content-Disposition: inline In-Reply-To: <20230501192829.17086-1-vishal.moola@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+glpr-linux-riscv=m.gmane-mx.org@lists.infradead.org To: "Vishal Moola (Oracle)" Cc: Andrew Morton , Matthew Wilcox , linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, loongarch@lists.linux.dev, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-openrisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, Catalin Marinas , Huacai Chen , Geert Uytterhoeven , Thomas Bogendoerfer , Dinh Nguyen , Jonas Bonn , David Hildenbrand , Claudio Imbrenda <> On Mon, May 01, 2023 at 12:27:55PM -0700, Vishal Moola (Oracle) wrote: > The MM subsystem is trying to shrink struct page. This patchset > introduces a memory descriptor for page table tracking - struct ptdesc. > > This patchset introduces ptdesc, splits ptdesc from struct page, and > converts many callers of page table constructor/destructors to use ptdescs. Lightly related food for future thought - based on some discussions at LSF/MM it would be really nice if an end result of this was that a rcu_head was always available in the ptdesc so we don't need to allocate memory to free a page table. Jason