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Thu, 02 Feb 2023 02:59:06 -0800 (PST) Received: from redhat.com ([46.136.252.173]) by smtp.gmail.com with ESMTPSA id j2-20020a5d4482000000b002be063f6820sm21295417wrq.81.2023.02.02.02.59.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Feb 2023 02:59:05 -0800 (PST) From: Juan Quintela To: Chuang Xu Cc: qemu-devel@nongnu.org, dgilbert@redhat.com, pbonzini@redhat.com, peterx@redhat.com, david@redhat.com, philmd@linaro.org, zhouyibo@bytedance.com Subject: Re: [RFC v5 1/3] rcu: introduce rcu_read_is_locked() In-Reply-To: <20230117115511.3215273-2-xuchuangxclwt@bytedance.com> (Chuang Xu's message of "Tue, 17 Jan 2023 19:55:09 +0800") References: <20230117115511.3215273-1-xuchuangxclwt@bytedance.com> <20230117115511.3215273-2-xuchuangxclwt@bytedance.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) Date: Thu, 02 Feb 2023 11:59:05 +0100 Message-ID: <87r0v8s58m.fsf@secure.mitica> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=170.10.129.124; envelope-from=quintela@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Chuang Xu wrote: > add rcu_read_is_locked() to detect holding of rcu lock. > > Signed-off-by: Chuang Xu Reviewed-by: Juan Quintela Althought I think that petting a review from Paolo or anyone that knows more than RCU could be a good idea. > --- > include/qemu/rcu.h | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/include/qemu/rcu.h b/include/qemu/rcu.h > index b063c6fde8..719916d9d3 100644 > --- a/include/qemu/rcu.h > +++ b/include/qemu/rcu.h > @@ -119,6 +119,13 @@ static inline void rcu_read_unlock(void) > } > } > > +static inline bool rcu_read_is_locked(void) > +{ > + struct rcu_reader_data *p_rcu_reader = get_ptr_rcu_reader(); > + > + return p_rcu_reader->depth > 0; > +} > + > extern void synchronize_rcu(void); > > /*