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[66.111.4.26]) by mx.google.com with ESMTPS id g5si1425154qvo.25.2019.03.11.18.06.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 Mar 2019 18:06:49 -0700 (PDT) Received-SPF: neutral (google.com: 66.111.4.26 is neither permitted nor denied by best guess record for domain of me@tobin.cc) client-ip=66.111.4.26; Authentication-Results: mx.google.com; dkim=pass header.i=@tobin.cc header.s=fm2 header.b=FTG5XdsL; dkim=pass header.i=@messagingengine.com header.s=fm2 header.b=uXdN5KnI; spf=neutral (google.com: 66.111.4.26 is neither permitted nor denied by best guess record for domain of me@tobin.cc) smtp.mailfrom=me@tobin.cc Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailout.nyi.internal (Postfix) with ESMTP id 60946226F4; Mon, 11 Mar 2019 21:06:49 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute5.internal (MEProxy); Mon, 11 Mar 2019 21:06:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tobin.cc; h=date :from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm2; bh=SKFjXI0K92phygeb6zeAtC318Fs cuxRVk6ZzNAcru7Q=; b=FTG5XdsLeuGuBvKBeti0SgcdASf3754kkTOHhi/bBRF UOr245JLFX8HDfXZoouLZYIMXdjnSvy6F8UYtZwcS7/wQ508jo7dFkQQULoXitHG +ztnzs+RtS0UABYkcN+rR1VaXYcwhDqODdtXbUponza4JJNa8iRkHXiu9S+fVo/X 6MTAIupieY+N3qniHBWcTmaCiEYLEKD6b4c2Ap7cAPiEmPMqUs061VvwfJqGo3Lk y3CVzbR1rcRyJQOcEE2BpUYad4mLBoc7KxH1JoDM3JiT6jgLW3jhFq+PhOhJmg0S GhRjFFUulubefDcY60ocenfTB5SkWo9R/4zhJqX1+yA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=SKFjXI 0K92phygeb6zeAtC318FscuxRVk6ZzNAcru7Q=; b=uXdN5KnIuWOlNl8kh72Or6 BHgmlWp4Peo46kypXqnmghVuQQfbx/NWnQkyfMh/KE5wd2xfp+AMUEsyJYMwazc5 gwZaM2es+vLhg6C470lfcrYMY0GJgtRw6L/sOXCbGCDgET/ebGiEgVLCBrf3+MAI axFUPOq/nM+2Kc4yy7r3vwc45rzGH9sh63Zd4tbRom6uSA1n6Fy25Z+UaqTuc+kh fIJHbYiBFRW4IvSvLf+5VSSpnF6lN+EhCm2DY+ZnSbTwa8AUP3j9Yp9sn6KO08Tv VJq9RLHLpaSYELDd/NobaWHJDT8fShqwaRl7eE3KaXtv9YXwJGlrLT6yvKrREPuQ == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedutddrgeejgddviecutefuodetggdotefrodftvf curfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfghnecu uegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenfg hrlhcuvffnffculdduhedmnecujfgurhepfffhvffukfhfgggtuggjofgfsehttdertdfo redvnecuhfhrohhmpedfvfhosghinhcuvedrucfjrghrughinhhgfdcuoehmvgesthhosg hinhdrtggtqeenucfkphepuddvgedrudeiledrvdefrddukeegnecurfgrrhgrmhepmhgr ihhlfhhrohhmpehmvgesthhosghinhdrtggtnecuvehluhhsthgvrhfuihiivgepud X-ME-Proxy: Received: from localhost (124-169-23-184.dyn.iinet.net.au [124.169.23.184]) by mail.messagingengine.com (Postfix) with ESMTPA id 768191033A; Mon, 11 Mar 2019 21:06:48 -0400 (EDT) Date: Tue, 12 Mar 2019 12:06:28 +1100 From: "Tobin C. Harding" To: Roman Gushchin Cc: Matthew Wilcox , "Tobin C. Harding" , Andrew Morton , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 0/4] mm: Use slab_list list_head instead of lru Message-ID: <20190312010628.GB9362@eros.localdomain> References: <20190311010744.5862-1-tobin@kernel.org> <20190311204919.GA20002@tower.DHCP.thefacebook.com> <20190311231633.GF19508@bombadil.infradead.org> <20190312002217.GA31718@tower.DHCP.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190312002217.GA31718@tower.DHCP.thefacebook.com> X-Mailer: Mutt 1.11.3 (2019-02-01) User-Agent: Mutt/1.11.3 (2019-02-01) 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: On Tue, Mar 12, 2019 at 12:22:23AM +0000, Roman Gushchin wrote: > On Mon, Mar 11, 2019 at 04:16:33PM -0700, Matthew Wilcox wrote: > > On Mon, Mar 11, 2019 at 08:49:23PM +0000, Roman Gushchin wrote: > > > The patchset looks good to me, however I'd add some clarifications > > > why switching from lru to slab_list is safe. > > > > > > My understanding is that the slab_list fields isn't currently in use, > > > but it's not that obvious that putting slab_list and next/pages/pobjects > > > fields into a union is safe (for the slub case). > > > > It's already in a union. > > > > struct page { > > union { > > struct { /* Page cache and anonymous pages */ > > struct list_head lru; > > ... > > struct { /* slab, slob and slub */ > > union { > > struct list_head slab_list; /* uses lru */ > > struct { /* Partial pages */ > > struct page *next; > > > > slab_list and lru are in the same bits. Once this patch set is in, > > we can remove the enigmatic 'uses lru' comment that I added. > > Ah, perfect, thanks! Makes total sense then. > > Tobin, can you, please, add a note to the commit message? > With the note: > Reviewed-by: Roman Gushchin Thanks for the review Roman, will add tag to v2. Tobin.