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[82.53.134.98]) by smtp.gmail.com with ESMTPSA id wy8-20020a170906fe0800b0093e261cc8bcsm1113313ejb.58.2023.03.24.08.39.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Mar 2023 08:39:59 -0700 (PDT) From: Stefano Garzarella To: virtualization@lists.linux-foundation.org Cc: Andrey Zhadchenko , Jason Wang , eperezma@redhat.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, kvm@vger.kernel.org, stefanha@redhat.com, "Michael S. Tsirkin" , Stefano Garzarella Subject: [PATCH v4 8/9] vdpa_sim: replace the spinlock with a mutex to protect the state Date: Fri, 24 Mar 2023 16:39:49 +0100 Message-Id: <20230324153949.47778-1-sgarzare@redhat.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230324153607.46836-1-sgarzare@redhat.com> References: <20230324153607.46836-1-sgarzare@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The spinlock we use to protect the state of the simulator is sometimes held for a long time (for example, when devices handle requests). This also prevents us from calling functions that might sleep (such as kthread_flush_work() in the next patch), and thus having to release and retake the lock. For these reasons, let's replace the spinlock with a mutex that gives us more flexibility. Suggested-by: Jason Wang Acked-by: Jason Wang Signed-off-by: Stefano Garzarella --- drivers/vdpa/vdpa_sim/vdpa_sim.h | 4 ++-- drivers/vdpa/vdpa_sim/vdpa_sim.c | 34 ++++++++++++++-------------- drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 4 ++-- drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 4 ++-- 4 files changed, 23 insertions(+), 23 deletions(-) diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_= sim.h index ce83f9130a5d..4774292fba8c 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h @@ -60,8 +60,8 @@ struct vdpasim { struct kthread_worker *worker; struct kthread_work work; struct vdpasim_dev_attr dev_attr; - /* spinlock to synchronize virtqueue state */ - spinlock_t lock; + /* mutex to synchronize virtqueue state */ + struct mutex mutex; /* virtio config according to device type */ void *config; struct vhost_iotlb *iommu; diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_= sim.c index bd9f9054de94..2b2e439a66f7 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c @@ -178,7 +178,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr = *dev_attr, if (IS_ERR(vdpasim->worker)) goto err_iommu; =20 - spin_lock_init(&vdpasim->lock); + mutex_init(&vdpasim->mutex); spin_lock_init(&vdpasim->iommu_lock); =20 dev->dma_mask =3D &dev->coherent_dma_mask; @@ -286,13 +286,13 @@ static void vdpasim_set_vq_ready(struct vdpa_device *= vdpa, u16 idx, bool ready) struct vdpasim_virtqueue *vq =3D &vdpasim->vqs[idx]; bool old_ready; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); old_ready =3D vq->ready; vq->ready =3D ready; if (vq->ready && !old_ready) { vdpasim_queue_ready(vdpasim, idx); } - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); } =20 static bool vdpasim_get_vq_ready(struct vdpa_device *vdpa, u16 idx) @@ -310,9 +310,9 @@ static int vdpasim_set_vq_state(struct vdpa_device *vdp= a, u16 idx, struct vdpasim_virtqueue *vq =3D &vdpasim->vqs[idx]; struct vringh *vrh =3D &vq->vring; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vrh->last_avail_idx =3D state->split.avail_index; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return 0; } @@ -409,9 +409,9 @@ static u8 vdpasim_get_status(struct vdpa_device *vdpa) struct vdpasim *vdpasim =3D vdpa_to_sim(vdpa); u8 status; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); status =3D vdpasim->status; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return status; } @@ -420,19 +420,19 @@ static void vdpasim_set_status(struct vdpa_device *vd= pa, u8 status) { struct vdpasim *vdpasim =3D vdpa_to_sim(vdpa); =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->status =3D status; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); } =20 static int vdpasim_reset(struct vdpa_device *vdpa) { struct vdpasim *vdpasim =3D vdpa_to_sim(vdpa); =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->status =3D 0; vdpasim_do_reset(vdpasim); - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return 0; } @@ -441,9 +441,9 @@ static int vdpasim_suspend(struct vdpa_device *vdpa) { struct vdpasim *vdpasim =3D vdpa_to_sim(vdpa); =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->running =3D false; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return 0; } @@ -453,7 +453,7 @@ static int vdpasim_resume(struct vdpa_device *vdpa) struct vdpasim *vdpasim =3D vdpa_to_sim(vdpa); int i; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->running =3D true; =20 if (vdpasim->pending_kick) { @@ -464,7 +464,7 @@ static int vdpasim_resume(struct vdpa_device *vdpa) vdpasim->pending_kick =3D false; } =20 - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return 0; } @@ -536,14 +536,14 @@ static int vdpasim_set_group_asid(struct vdpa_device = *vdpa, unsigned int group, =20 iommu =3D &vdpasim->iommu[asid]; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); =20 for (i =3D 0; i < vdpasim->dev_attr.nvqs; i++) if (vdpasim_get_vq_group(vdpa, i) =3D=3D group) vringh_set_iotlb(&vdpasim->vqs[i].vring, iommu, &vdpasim->iommu_lock); =20 - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 return 0; } diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/v= dpa_sim_blk.c index eb4897c8541e..568119e1553f 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c @@ -290,7 +290,7 @@ static void vdpasim_blk_work(struct vdpasim *vdpasim) bool reschedule =3D false; int i; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); =20 if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) goto out; @@ -321,7 +321,7 @@ static void vdpasim_blk_work(struct vdpasim *vdpasim) } } out: - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 if (reschedule) vdpasim_schedule_work(vdpasim); diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/v= dpa_sim_net.c index e61a9ecbfafe..7ab434592bfe 100644 --- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c +++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c @@ -201,7 +201,7 @@ static void vdpasim_net_work(struct vdpasim *vdpasim) u64 rx_drops =3D 0, rx_overruns =3D 0, rx_errors =3D 0, tx_errors =3D 0; int err; =20 - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); =20 if (!vdpasim->running) goto out; @@ -264,7 +264,7 @@ static void vdpasim_net_work(struct vdpasim *vdpasim) } =20 out: - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); =20 u64_stats_update_begin(&net->tx_stats.syncp); net->tx_stats.pkts +=3D tx_pkts; --=20 2.39.2