From d7621c28fca1c16f9e94245479792024a5676c50 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella Date: Tue, 4 Apr 2023 15:17:29 +0200 Subject: [PATCH] vdpa_sim: replace the spinlock with a mutex to protect the state 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 Message-Id: <20230404131730.45920-1-sgarzare@redhat.com> Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/vdpa_sim/vdpa_sim.c | 34 ++++++++++++++-------------- drivers/vdpa/vdpa_sim/vdpa_sim.h | 4 ++-- 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.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; - spin_lock_init(&vdpasim->lock); + mutex_init(&vdpasim->mutex); spin_lock_init(&vdpasim->iommu_lock); dev->dma_mask = &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 = &vdpasim->vqs[idx]; bool old_ready; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); old_ready = vq->ready; vq->ready = ready; if (vq->ready && !old_ready) { vdpasim_queue_ready(vdpasim, idx); } - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); } 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 *vdpa, u16 idx, struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx]; struct vringh *vrh = &vq->vring; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vrh->last_avail_idx = state->split.avail_index; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return 0; } @@ -409,9 +409,9 @@ static u8 vdpasim_get_status(struct vdpa_device *vdpa) struct vdpasim *vdpasim = vdpa_to_sim(vdpa); u8 status; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); status = vdpasim->status; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return status; } @@ -420,19 +420,19 @@ static void vdpasim_set_status(struct vdpa_device *vdpa, u8 status) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->status = status; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); } static int vdpasim_reset(struct vdpa_device *vdpa) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->status = 0; vdpasim_do_reset(vdpasim); - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return 0; } @@ -441,9 +441,9 @@ static int vdpasim_suspend(struct vdpa_device *vdpa) { struct vdpasim *vdpasim = vdpa_to_sim(vdpa); - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->running = false; - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return 0; } @@ -453,7 +453,7 @@ static int vdpasim_resume(struct vdpa_device *vdpa) struct vdpasim *vdpasim = vdpa_to_sim(vdpa); int i; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); vdpasim->running = true; if (vdpasim->pending_kick) { @@ -464,7 +464,7 @@ static int vdpasim_resume(struct vdpa_device *vdpa) vdpasim->pending_kick = false; } - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return 0; } @@ -536,14 +536,14 @@ static int vdpasim_set_group_asid(struct vdpa_device *vdpa, unsigned int group, iommu = &vdpasim->iommu[asid]; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); for (i = 0; i < vdpasim->dev_attr.nvqs; i++) if (vdpasim_get_vq_group(vdpa, i) == group) vringh_set_iotlb(&vdpasim->vqs[i].vring, iommu, &vdpasim->iommu_lock); - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); return 0; } 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_blk.c b/drivers/vdpa/vdpa_sim/vdpa_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 = false; int i; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); 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); if (reschedule) vdpasim_schedule_work(vdpasim); diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c index 30ac41c5827e..55920502f76b 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 = 0, rx_overruns = 0, rx_errors = 0, tx_errors = 0; int err; - spin_lock(&vdpasim->lock); + mutex_lock(&vdpasim->mutex); if (!vdpasim->running) goto out; @@ -264,7 +264,7 @@ static void vdpasim_net_work(struct vdpasim *vdpasim) } out: - spin_unlock(&vdpasim->lock); + mutex_unlock(&vdpasim->mutex); u64_stats_update_begin(&net->tx_stats.syncp); net->tx_stats.pkts += tx_pkts;