Return-Path: Received: from mx143.netapp.com ([216.240.21.24]:60084 "EHLO mx143.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752097AbcIZU40 (ORCPT ); Mon, 26 Sep 2016 16:56:26 -0400 Subject: =?UTF-8?Q?Re:_=e7=ad=94=e5=a4=8d:_[PATCH]_sunrpc:_queue_work_on_sys?= =?UTF-8?Q?tem=5fpower=5fefficient=5fwq?= To: =?UTF-8?B?S2UgV2FuZyAo546L56eRKQ==?= , Chunyan Zhang , "trond.myklebust@primarydata.com" , "davem@davemloft.net" References: <1472715026-11397-1-git-send-email-zhang.lyra@gmail.com> <544e309c-9893-a0ed-ab8a-ccbf5d342dc6@Netapp.com> CC: "linux-nfs@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" From: Anna Schumaker Message-ID: <0828f346-2e30-afb4-6e90-cdefaf5df36f@Netapp.com> Date: Mon, 26 Sep 2016 16:56:08 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: Hi, I took a second look at the patch and it still looks okay to me. It's in my git tree for 4.9. Thanks, Anna On 09/19/2016 10:33 PM, Ke Wang (王科) wrote: > May I have any comments for this patch? > or > This patch can be merged directly into next release? > > Thanks, > Ke > ________________________________________ > 发件人: Anna Schumaker > 发送时间: 2016年9月2日 2:46 > 收件人: Chunyan Zhang; trond.myklebust@primarydata.com; anna.schumaker@netapp.com; davem@davemloft.net > 抄送: linux-nfs@vger.kernel.org; netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Ke Wang (王科) > 主题: Re: [PATCH] sunrpc: queue work on system_power_efficient_wq > > On 09/01/2016 03:30 AM, Chunyan Zhang wrote: >> From: Ke Wang >> >> sunrpc uses workqueue to clean cache regulary. There is no real dependency >> of executing work on the cpu which queueing it. >> >> On a idle system, especially for a heterogeneous systems like big.LITTLE, >> it is observed that the big idle cpu was woke up many times just to service >> this work, which against the principle of power saving. It would be better >> if we can schedule it on a cpu which the scheduler believes to be the most >> appropriate one. >> >> After apply this patch, system_wq will be replaced by >> system_power_efficient_wq for sunrpc. This functionality is enabled when >> CONFIG_WQ_POWER_EFFICIENT is selected. > > Makes sense to me, but I'm a little surprised that there isn't a "schedule_delayed_power_efficient_work()" function to match how the normal workqueue is used. > > Thanks, > Anna > >> >> Signed-off-by: Ke Wang >> --- >> net/sunrpc/cache.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c >> index 4d8e11f..8aabe12 100644 >> --- a/net/sunrpc/cache.c >> +++ b/net/sunrpc/cache.c >> @@ -353,7 +353,7 @@ void sunrpc_init_cache_detail(struct cache_detail *cd) >> spin_unlock(&cache_list_lock); >> >> /* start the cleaning process */ >> - schedule_delayed_work(&cache_cleaner, 0); >> + queue_delayed_work(system_power_efficient_wq, &cache_cleaner, 0); >> } >> EXPORT_SYMBOL_GPL(sunrpc_init_cache_detail); >> >> @@ -476,7 +476,8 @@ static void do_cache_clean(struct work_struct *work) >> delay = 0; >> >> if (delay) >> - schedule_delayed_work(&cache_cleaner, delay); >> + queue_delayed_work(system_power_efficient_wq, >> + &cache_cleaner, delay); >> } >> >> >> >