search for: atomic_sub_return

...gt;send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) + vhost_poll_queue(&tx_vq->poll); + } + + return 0; +} + static struct virtio_vsock_pkt * vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, unsigned int out, unsi...

...gt;send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) + vhost_poll_queue(&tx_vq->poll); + } + + return 0; +} + static struct virtio_vsock_pkt * vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, unsigned int out, unsi...

...is sometimes useful to get the value of the reference count after decrement. For example, vhost wants to execute some periodic cleanup operations once number of references drops below a specific value, before it reaches zero (for efficiency). Add an API to do this atomically and efficiently using atomic_sub_return. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- Greg, could you ack this API extension please? I think it is cleanest to merge this through -net together with the first user. include/linux/kref.h | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 delet...

...mation) kallsyms unmap_page_range 1123 100.000 (no location information) kallsyms unmap_page_range [self] ------------------------------------------------------------------------------- 1088 0.5242 (no location information) kallsyms atomic_sub_return.constprop.3 1088 100.000 (no location information) kallsyms atomic_sub_return.constprop.3 [self] ------------------------------------------------------------------------------- pixman/memcpy dominating initial profile probably OK, because guest uses vesa driver and KDE4 w...

This fixes a deadlock with vhost reported in the field, as well as a theoretical race issue found by code review. Patches 1+2 are needed for stable. Thanks to Qin Chuanyu for reporting the issue! Michael S. Tsirkin (3): kref: add kref_sub_return vhost: fix ref cnt checking deadlock vhost: fix a theoretical race in device cleanup include/linux/kref.h | 33

This fixes a deadlock with vhost reported in the field, as well as a theoretical race issue found by code review. Patches 1+2 are needed for stable. Thanks to Qin Chuanyu for reporting the issue! Michael S. Tsirkin (3): kref: add kref_sub_return vhost: fix ref cnt checking deadlock vhost: fix a theoretical race in device cleanup include/linux/kref.h | 33

...gt;send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) + vhost_poll_queue(&tx_vq->poll); + } + + return 0; +} + static struct virtio_vsock_pkt * vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, unsigned int out, unsi...

...gt;send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) + vhost_poll_queue(&tx_vq->poll); + } + + return 0; +} + static struct virtio_vsock_pkt * vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, unsigned int out, unsi...

...1); init_waitqueue_head(&ubufs->wait); ubufs->vq = vq; return ubufs; } -static void vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) +static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) { - kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); + int r = atomic_sub_return(1, &ubufs->refcount); + if (unlikely(!r)) + wake_up(&ubufs->wait); + return r; } static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) { - kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); - wait_event(ubufs->wait, !atomic_read(&ubufs->...

...1); init_waitqueue_head(&ubufs->wait); ubufs->vq = vq; return ubufs; } -static void vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) +static int vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs) { - kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); + int r = atomic_sub_return(1, &ubufs->refcount); + if (unlikely(!r)) + wake_up(&ubufs->wait); + return r; } static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs) { - kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal); - wait_event(ubufs->wait, !atomic_read(&ubufs->...

Hi David, These patchsets were sent before and reviewed by Stefan and Jorgen [https://www.spinics.net/lists/kvm/msg142367.html]. If there is any blocker, please do tell and I'll see to it. Thanks! Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent

Hi David, These patchsets were sent before and reviewed by Stefan and Jorgen [https://www.spinics.net/lists/kvm/msg142367.html]. If there is any blocker, please do tell and I'll see to it. Thanks! Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent

Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent even though the connection is considered a failure, which can confuse applications with unwanted false connect attempt. The patchset enables vsock (both host and guest) to cancel queued packets when a

Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent even though the connection is considered a failure, which can confuse applications with unwanted false connect attempt. The patchset enables vsock (both host and guest) to cancel queued packets when a

...gt;send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= tx_vq->num && new_cnt < tx_vq->num) + vhost_poll_queue(&tx_vq->poll); + } + + return 0; +} + static struct virtio_vsock_pkt * vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, unsigned int out, unsi...

...amp;vsock->send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= virtqueue_get_vring_size(rx_vq) && + new_cnt < virtqueue_get_vring_size(rx_vq)) + queue_work(virtio_vsock_workqueue, &vsock->rx_work); + } + + return 0; +} + static void virtio_vsock_rx_fill(struct virtio_vsoc...

...amp;vsock->send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= virtqueue_get_vring_size(rx_vq) && + new_cnt < virtqueue_get_vring_size(rx_vq)) + queue_work(virtio_vsock_workqueue, &vsock->rx_work); + } + + return 0; +} + static void virtio_vsock_rx_fill(struct virtio_vsoc...

...amp;vsock->send_pkt_list_lock); + + list_for_each_entry_safe(pkt, n, &freeme, list) { + if (pkt->reply) + cnt++; + list_del(&pkt->list); + virtio_transport_free_pkt(pkt); + } + + if (cnt) { + struct virtqueue *rx_vq = vsock->vqs[VSOCK_VQ_RX]; + int new_cnt; + + new_cnt = atomic_sub_return(cnt, &vsock->queued_replies); + if (new_cnt + cnt >= virtqueue_get_vring_size(rx_vq) && + new_cnt < virtqueue_get_vring_size(rx_vq)) + queue_work(virtio_vsock_workqueue, &vsock->rx_work); + } + + return 0; +} + static void virtio_vsock_rx_fill(struct virtio_vsoc...

Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent even though the connection is considered a failure, which can confuse applications with unwanted false connect attempt. The patchset enables vsock (both host and guest) to cancel queued packets when a

Currently, if a connect call fails on a signal or timeout (e.g., guest is still in the process of starting up), we'll just return to caller and leave the connect packet queued and they are sent even though the connection is considered a failure, which can confuse applications with unwanted false connect attempt. The patchset enables vsock (both host and guest) to cancel queued packets when a