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Wed, 4 Jan 2023 14:20:54 +0000 (GMT) References: <20221223142307.1614945-1-xuchuangxclwt@bytedance.com> <20221223142307.1614945-2-xuchuangxclwt@bytedance.com> User-agent: mu4e 1.9.11; emacs 29.0.60 From: Alex =?utf-8?Q?Benn=C3=A9e?= To: Chuang Xu Cc: dgilbert@redhat.com, quintela@redhat.com, pbonzini@redhat.com, peterx@redhat.com, david@redhat.com, philmd@linaro.org, zhouyibo@bytedance.com, qemu-devel@nongnu.org Subject: Re: [RFC v4 1/3] rcu: introduce rcu_read_locked() Date: Wed, 04 Jan 2023 14:20:02 +0000 In-reply-to: <20221223142307.1614945-2-xuchuangxclwt@bytedance.com> Message-ID: <87zgaypeih.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2a00:1450:4864:20::335; envelope-from=alex.bennee@linaro.org; helo=mail-wm1-x335.google.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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: , 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 writes: > add rcu_read_locked() to detect holding of rcu lock. > > Signed-off-by: Chuang Xu > --- > include/qemu/rcu.h | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/include/qemu/rcu.h b/include/qemu/rcu.h > index b063c6fde8..42cbd0080f 100644 > --- a/include/qemu/rcu.h > +++ b/include/qemu/rcu.h > @@ -119,6 +119,13 @@ static inline void rcu_read_unlock(void) > } > } >=20=20 > +static inline bool rcu_read_locked(void) We use the locked suffix to indicate functions that should be called with a lock held. Perhaps renaming this to rcu_read_is_locked() would make the intent of the function clearer? > +{ > + struct rcu_reader_data *p_rcu_reader =3D get_ptr_rcu_reader(); > + > + return p_rcu_reader->depth > 0; > +} > + > extern void synchronize_rcu(void); >=20=20 > /* --=20 Alex Benn=C3=A9e Virtualisation Tech Lead @ Linaro