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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C93EC433EF for ; Tue, 1 Mar 2022 23:50:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231547AbiCAXvR (ORCPT ); Tue, 1 Mar 2022 18:51:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34694 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231490AbiCAXvQ (ORCPT ); Tue, 1 Mar 2022 18:51:16 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 576CD61A15; Tue, 1 Mar 2022 15:50:35 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 0C32EB81EA7; Tue, 1 Mar 2022 23:50:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68E51C340EE; Tue, 1 Mar 2022 23:50:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646178632; bh=BDy9HN55VjW0OXpj2rwgeo/0PzouCOspchdWJqyE92I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=n8buYiA5Xkt+q8CyWCxWZ7apeIUFPN9cIiAXgvymFb8EvDRYYA6i8g0FrZu8y066u 7hlvM60J3bOaN5p7f4s4J0oOeeIZEDmSPIpV32p2UhXJFLcAGRwLzowXzXLj21DXLD OnaMluWGZ+gG0cI2A1meYYvLuAvaDqbqGOFJLceqaXfV5WIA5sIydu8GkyThy8JW0/ 5FG1EBHUv1Yp1kl98/lObDwo7xvsrOubooirCnCwavbjHiX/68G3cJqGK/C32rzBaQ YJ09EL2UreSH09hYPK92Bw82XzUV4O9jvUcVk3kbck1cZ/LW8T5IOee43BsCGQ8UOG jPSpo6yNgnHOA== Date: Tue, 1 Mar 2022 15:50:31 -0800 From: Saeed Mahameed To: Joe Damato Cc: netdev@vger.kernel.org, kuba@kernel.org, ilias.apalodimas@linaro.org, davem@davemloft.net, hawk@kernel.org, ttoukan.linux@gmail.com, brouer@redhat.com, leon@kernel.org, linux-rdma@vger.kernel.org, saeedm@nvidia.com Subject: Re: [net-next v8 1/4] page_pool: Add allocation stats Message-ID: <20220301235031.ryy4trywlc3bmnpx@sx1> References: <1646172610-129397-1-git-send-email-jdamato@fastly.com> <1646172610-129397-2-git-send-email-jdamato@fastly.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <1646172610-129397-2-git-send-email-jdamato@fastly.com> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On 01 Mar 14:10, Joe Damato wrote: >Add per-pool statistics counters for the allocation path of a page pool. >These stats are incremented in softirq context, so no locking or per-cpu >variables are needed. > >This code is disabled by default and a kernel config option is provided for >users who wish to enable them. > Sorry for the late review Joe, Why disabled by default ? if your benchmarks showed no diff. IMHO If we believe in this, we should have it enabled by default. >The statistics added are: > - fast: successful fast path allocations > - slow: slow path order-0 allocations > - slow_high_order: slow path high order allocations > - empty: ptr ring is empty, so a slow path allocation was forced. > - refill: an allocation which triggered a refill of the cache > - waive: pages obtained from the ptr ring that cannot be added to > the cache due to a NUMA mismatch. > Let's have this documented under kernel documentation. https://docs.kernel.org/networking/page_pool.html I would also mention the kconfig and any user knobs APIs introduced in this series