From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E09BA1426B for ; Tue, 6 Feb 2024 17:38:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707241139; cv=none; b=NnkZRwTvFmzPotUdmq4A70Ei4kaojBNXXuwS6T9XF5P9iNOEpyzhFWtd2ab/L/VyTJJBYKzyJDomgrxUNbZ9eQUbkz3xSyA0baN22SQCPukf/n57sT1KiTXAtW+I03Lh4GIGJWi9ky3NV5Uqbf+dAejs8AA0WZ60t9zR5zf7h5w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707241139; c=relaxed/simple; bh=rb8APAK/NFsWkjSw2CEJHSFqUkeP73aN71SPR67A7Ck=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=GXGfetu46r7FTApI72lorztrUocnUVt1lCf3sKznolJLB49nI2yEC2TuhtG9Enegj5ppyenbYoEKKMARELsQBt4cjw4qT1HKp2zFTKfsvtSewkjFV1BEDgkE4ejGd8aKTNJbotPzoXqGvYAAE7M/vq8UTOnL9HscdsyKdxZQJnU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=lciMhFVw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="lciMhFVw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 244A1C433F1; Tue, 6 Feb 2024 17:38:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1707241138; bh=rb8APAK/NFsWkjSw2CEJHSFqUkeP73aN71SPR67A7Ck=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=lciMhFVwD8spj2zXqwGFIForrObq2F8BJkxbrdxDdYKg1fqbP5VAtqDJQUwue4+18 DItyjrNq9uxFdW2im98TsjO377IO4W5VqyMC915WTZkqw+Bcft2n+PVPZvdbs5uY3o Qv7TvTU/TNfcgzvgW8xsYVdhfUp+yQrigOvQyjRk= Date: Tue, 6 Feb 2024 09:38:57 -0800 From: Andrew Morton To: Anshuman Khandual Cc: linux-mm@kvack.org, alexandru.elisei@arm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/cma: Add sysfs file 'release_pages_success' Message-Id: <20240206093857.d834af4f96d643c53e29e02d@linux-foundation.org> In-Reply-To: <20240206045731.472759-1-anshuman.khandual@arm.com> References: <20240206045731.472759-1-anshuman.khandual@arm.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) 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-Transfer-Encoding: 7bit On Tue, 6 Feb 2024 10:27:31 +0530 Anshuman Khandual wrote: > This adds the following new sysfs file tracking the number of successfully > released pages from a given CMA heap area. Also like before - this will be > available via CONFIG_CMA_SYSFS, and help in determining active CMA pages > available on the system. "like before" is mysterious. Is this referring to some other patch? To existing code? Please be explicit and complete. > /sys/kernel/mm/cma//release_pages_success > > It adds an element 'nr_pages_released' (with CONFIG_CMA_SYSFS config) into > 'struct cma' which gets updated during cma_release(). The changelog doesn't explain why Linux needs this feature. The value to our users. Perhaps that info is buried in the link which is buried below the ^---$, but as this is the most important part of a changelog, it really should be spelled out here, completely and carefully please. > --- > This patch applies on v6.8-rc3 > > Some earlier relevant discussions regarding arm64 MTE dynamic tag storage > in this regard can be found here. > > https://lore.kernel.org/all/ZbpKyNVHfhf1-AAv@raptor/