From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 54A5C3115B5 for ; Mon, 10 Nov 2025 13:38:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762781933; cv=none; b=IEljLqQfwi+05T39H0XFUISCGOCUwwXeWiZ+by+RF3SQmwnhuGpUA0yQMaP+Fwi81UK1pIw3wTUtMl2EVehLA4N9TCRvis9h754USMVLFbJV9aol6PiNTDd/TdnNCcMB98e+3Yx0xTfc3OXaySVxBI1/cJO12SQbgcT0daTFxTk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762781933; c=relaxed/simple; bh=ESpxzLjRIYApwkHxl6Vgj10zCasBSSNB54DbKubFwY4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EtFbieHhOORIVdWHwg0LYhsdpvdi/JNdq10shXTetqUUDr+R0TMyxdFf2JqbxGZZpOgHJg/G6Si8spnYNb4Oe/l6izq0kGcVx1cvB5EYG5ApwY713tlWvuFimkjQDeQyph/zqXHjPjOX7F2dFUojlhJj5vx23o2eRhjPudlCAyI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=PQWMWyeA; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="PQWMWyeA" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=ESpxzLjRIYApwkHxl6Vgj10zCasBSSNB54DbKubFwY4=; b=PQWMWyeA36Wa+X7C9sAPrQru6l ZH8kPCH899xum93FMK/P+W/guoOk3C07s17/t3ZB+VfNQNbWUkeiKf/+3IQeKpYLj57WjgglQwMao 0aRS3BqQ0uTgr7qUgdBA8IzRaaBLylqYTEDAW6Zu8uBlpsPJiMJiiQJ19KA531Yq+BHC7oUSrJLUi itNxRLsDV0rsi+jrw/0HkwcxzPuiQMOp5mkg5gZ5v7TJGHf4hw6MsHMhk0xWjUwAY5VWex6KVOs06 1ZUGmNcLJ9x+1J/WmfxUDbQaGUtNh6vm5IoGxXpks9RjbdcAQZW+dOaQEglBAngDQ2sk5iCgt+4dE 2+YEy7vw==; Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1vIS6S-0000000GI3P-2js0; Mon, 10 Nov 2025 13:38:40 +0000 Date: Mon, 10 Nov 2025 13:38:40 +0000 From: Matthew Wilcox To: Anshuman Khandual Cc: linux-mm@kvack.org, vishal.moola@gmail.com, Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/ptdesc: Derive from the compound head in page_ptdesc() Message-ID: References: <20251110063725.3118037-1-anshuman.khandual@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251110063725.3118037-1-anshuman.khandual@arm.com> On Mon, Nov 10, 2025 at 06:37:25AM +0000, Anshuman Khandual wrote: > struct ptdesc (including all relevant helpers) support multi order compound > pages. But page_ptdesc() coverts given page into its own ptdesc rather than > deriving from its compound head as would have been expected otherwise. Just > change the macro to fetch the struct ptdesc from the compound head instead, > so that the same struct ptdesc is reached from all tail pages. Please review https://lore.kernel.org/linux-mm/20251020001652.2116669-1-willy@infradead.org/ instead.