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([2001:b07:6468:f312:c8dd:75d4:99ab:290a]) by smtp.gmail.com with ESMTPSA id rk9sm955443ejb.31.2021.10.20.05.04.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 Oct 2021 05:04:25 -0700 (PDT) Message-ID: Date: Wed, 20 Oct 2021 14:04:23 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.1.0 Subject: Re: [PATCH] rcuwait: do not enter RCU protection unless a wakeup is needed Content-Language: en-US To: Wanpeng Li Cc: Peter Zijlstra , LKML , kvm , Davidlohr Bueso , Oleg Nesterov , Ingo Molnar , "Paul E . McKenney" , Wanpeng Li References: <20211020110638.797389-1-pbonzini@redhat.com> <98a72081-6a2b-b644-d029-edd03da84135@redhat.com> From: Paolo Bonzini In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/10/21 14:01, Wanpeng Li wrote: > Yes, in the attachment. > > Wanpeng This one does not have CONFIG_PREEMPT=y, let alone CONFIG_PREEMPT_RCU. It's completely impossible that this patch has an effect without those options. Paolo