Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <41b404c7-78cb-8b5f-2b89-8ab7bd13ded9@linux.alibaba.com>
Date:   Mon, 25 Apr 2022 23:04:50 +0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0)
 Gecko/20100101 Thunderbird/91.7.0
Subject: Re: [PATCH v2] sched/core: Skip sched_core_fork/free() when core
 sched is disabled
Content-Language: en-US
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mingo@redhat.com, juri.lelli@redhat.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com,
        rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de,
        bristot@redhat.com, linux-kernel@vger.kernel.org
References: <1650831454-101777-1-git-send-email-CruzZhao@linux.alibaba.com>
 <20220425081410.GA2731@worktop.programming.kicks-ass.net>
From:   cruzzhao <cruzzhao@linux.alibaba.com>
In-Reply-To: <20220425081410.GA2731@worktop.programming.kicks-ass.net>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk


在 2022/4/25 下午4:14, Peter Zijlstra 写道:
> On Mon, Apr 25, 2022 at 04:17:34AM +0800, Cruz Zhao wrote:
>> As __put_task_struct() and copy_process() are hot path functions,
>> the call of sched_core_fork/free() will bring overhead when core
>> sched is disabled, and we skip them in these cases.
> 
> Only if you have profile data.. mostly these functions do whole lot of
> nothing.

Many thanks for suggestion, I'll test it.

Best wishes,
Cruz Zhao