Re: [PATCH v2 2/4] eventfd: simplify eventfd_signal()

[Stefan Hajnoczi <stefanha@gmail.com>]

vhost and VIRTIO-related parts:

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

On Wed, 22 Nov 2023 at 07:50, Christian Brauner <brauner@kernel.org> wrote:
>
> Ever since the evenfd type was introduced back in 2007 in commit
> e1ad7468c77d ("signal/timer/event: eventfd core") the eventfd_signal()
> function only ever passed 1 as a value for @n. There's no point in
> keeping that additional argument.
>
> Signed-off-by: Christian Brauner <brauner@kernel.org>
> ---
>  arch/x86/kvm/hyperv.c                     |  2 +-
>  arch/x86/kvm/xen.c                        |  2 +-
>  drivers/accel/habanalabs/common/device.c  |  2 +-
>  drivers/fpga/dfl.c                        |  2 +-
>  drivers/gpu/drm/drm_syncobj.c             |  6 +++---
>  drivers/gpu/drm/i915/gvt/interrupt.c      |  2 +-
>  drivers/infiniband/hw/mlx5/devx.c         |  2 +-
>  drivers/misc/ocxl/file.c                  |  2 +-
>  drivers/s390/cio/vfio_ccw_chp.c           |  2 +-
>  drivers/s390/cio/vfio_ccw_drv.c           |  4 ++--
>  drivers/s390/cio/vfio_ccw_ops.c           |  6 +++---
>  drivers/s390/crypto/vfio_ap_ops.c         |  2 +-
>  drivers/usb/gadget/function/f_fs.c        |  4 ++--
>  drivers/vdpa/vdpa_user/vduse_dev.c        |  6 +++---
>  drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c    |  2 +-
>  drivers/vfio/pci/vfio_pci_core.c          |  6 +++---
>  drivers/vfio/pci/vfio_pci_intrs.c         | 12 ++++++------
>  drivers/vfio/platform/vfio_platform_irq.c |  4 ++--
>  drivers/vhost/vdpa.c                      |  4 ++--
>  drivers/vhost/vhost.c                     | 10 +++++-----
>  drivers/vhost/vhost.h                     |  2 +-
>  drivers/virt/acrn/ioeventfd.c             |  2 +-
>  drivers/xen/privcmd.c                     |  2 +-
>  fs/aio.c                                  |  2 +-
>  fs/eventfd.c                              |  9 +++------
>  include/linux/eventfd.h                   |  4 ++--
>  mm/memcontrol.c                           | 10 +++++-----
>  mm/vmpressure.c                           |  2 +-
>  samples/vfio-mdev/mtty.c                  |  4 ++--
>  virt/kvm/eventfd.c                        |  4 ++--
>  30 files changed, 60 insertions(+), 63 deletions(-)
>
> diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
> index 238afd7335e4..4943f6b2bbee 100644
> --- a/arch/x86/kvm/hyperv.c
> +++ b/arch/x86/kvm/hyperv.c
> @@ -2388,7 +2388,7 @@ static u16 kvm_hvcall_signal_event(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *h
>         if (!eventfd)
>                 return HV_STATUS_INVALID_PORT_ID;
>
> -       eventfd_signal(eventfd, 1);
> +       eventfd_signal(eventfd);
>         return HV_STATUS_SUCCESS;
>  }
>
> diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
> index e53fad915a62..523bb6df5ac9 100644
> --- a/arch/x86/kvm/xen.c
> +++ b/arch/x86/kvm/xen.c
> @@ -2088,7 +2088,7 @@ static bool kvm_xen_hcall_evtchn_send(struct kvm_vcpu *vcpu, u64 param, u64 *r)
>                 if (ret < 0 && ret != -ENOTCONN)
>                         return false;
>         } else {
> -               eventfd_signal(evtchnfd->deliver.eventfd.ctx, 1);
> +               eventfd_signal(evtchnfd->deliver.eventfd.ctx);
>         }
>
>         *r = 0;
> diff --git a/drivers/accel/habanalabs/common/device.c b/drivers/accel/habanalabs/common/device.c
> index 9711e8fc979d..3a89644f087c 100644
> --- a/drivers/accel/habanalabs/common/device.c
> +++ b/drivers/accel/habanalabs/common/device.c
> @@ -2044,7 +2044,7 @@ static void hl_notifier_event_send(struct hl_notifier_event *notifier_event, u64
>         notifier_event->events_mask |= event_mask;
>
>         if (notifier_event->eventfd)
> -               eventfd_signal(notifier_event->eventfd, 1);
> +               eventfd_signal(notifier_event->eventfd);
>
>         mutex_unlock(&notifier_event->lock);
>  }
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index dd7a783d53b5..e73f88050f08 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -1872,7 +1872,7 @@ static irqreturn_t dfl_irq_handler(int irq, void *arg)
>  {
>         struct eventfd_ctx *trigger = arg;
>
> -       eventfd_signal(trigger, 1);
> +       eventfd_signal(trigger);
>         return IRQ_HANDLED;
>  }
>
> diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c
> index 01da6789d044..b9cc62982196 100644
> --- a/drivers/gpu/drm/drm_syncobj.c
> +++ b/drivers/gpu/drm/drm_syncobj.c
> @@ -1365,7 +1365,7 @@ static void syncobj_eventfd_entry_fence_func(struct dma_fence *fence,
>         struct syncobj_eventfd_entry *entry =
>                 container_of(cb, struct syncobj_eventfd_entry, fence_cb);
>
> -       eventfd_signal(entry->ev_fd_ctx, 1);
> +       eventfd_signal(entry->ev_fd_ctx);
>         syncobj_eventfd_entry_free(entry);
>  }
>
> @@ -1388,13 +1388,13 @@ syncobj_eventfd_entry_func(struct drm_syncobj *syncobj,
>         entry->fence = fence;
>
>         if (entry->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) {
> -               eventfd_signal(entry->ev_fd_ctx, 1);
> +               eventfd_signal(entry->ev_fd_ctx);
>                 syncobj_eventfd_entry_free(entry);
>         } else {
>                 ret = dma_fence_add_callback(fence, &entry->fence_cb,
>                                              syncobj_eventfd_entry_fence_func);
>                 if (ret == -ENOENT) {
> -                       eventfd_signal(entry->ev_fd_ctx, 1);
> +                       eventfd_signal(entry->ev_fd_ctx);
>                         syncobj_eventfd_entry_free(entry);
>                 }
>         }
> diff --git a/drivers/gpu/drm/i915/gvt/interrupt.c b/drivers/gpu/drm/i915/gvt/interrupt.c
> index 9665876b4b13..7f4db438e400 100644
> --- a/drivers/gpu/drm/i915/gvt/interrupt.c
> +++ b/drivers/gpu/drm/i915/gvt/interrupt.c
> @@ -454,7 +454,7 @@ static void inject_virtual_interrupt(struct intel_vgpu *vgpu)
>                 return;
>         if (!vgpu->msi_trigger)
>                 return;
> -       eventfd_signal(vgpu->msi_trigger, 1);
> +       eventfd_signal(vgpu->msi_trigger);
>  }
>
>  static void propagate_event(struct intel_gvt_irq *irq,
> diff --git a/drivers/infiniband/hw/mlx5/devx.c b/drivers/infiniband/hw/mlx5/devx.c
> index 8ba53edf2311..869369cb5b5f 100644
> --- a/drivers/infiniband/hw/mlx5/devx.c
> +++ b/drivers/infiniband/hw/mlx5/devx.c
> @@ -2498,7 +2498,7 @@ static void dispatch_event_fd(struct list_head *fd_list,
>
>         list_for_each_entry_rcu(item, fd_list, xa_list) {
>                 if (item->eventfd)
> -                       eventfd_signal(item->eventfd, 1);
> +                       eventfd_signal(item->eventfd);
>                 else
>                         deliver_event(item, data);
>         }
> diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
> index ac69b7f361f5..7eb74711ac96 100644
> --- a/drivers/misc/ocxl/file.c
> +++ b/drivers/misc/ocxl/file.c
> @@ -184,7 +184,7 @@ static irqreturn_t irq_handler(void *private)
>  {
>         struct eventfd_ctx *ev_ctx = private;
>
> -       eventfd_signal(ev_ctx, 1);
> +       eventfd_signal(ev_ctx);
>         return IRQ_HANDLED;
>  }
>
> diff --git a/drivers/s390/cio/vfio_ccw_chp.c b/drivers/s390/cio/vfio_ccw_chp.c
> index d3f3a611f95b..38c176cf6295 100644
> --- a/drivers/s390/cio/vfio_ccw_chp.c
> +++ b/drivers/s390/cio/vfio_ccw_chp.c
> @@ -115,7 +115,7 @@ static ssize_t vfio_ccw_crw_region_read(struct vfio_ccw_private *private,
>
>         /* Notify the guest if more CRWs are on our queue */
>         if (!list_empty(&private->crw) && private->crw_trigger)
> -               eventfd_signal(private->crw_trigger, 1);
> +               eventfd_signal(private->crw_trigger);
>
>         return ret;
>  }
> diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
> index 43601816ea4e..bfb35cfce1ef 100644
> --- a/drivers/s390/cio/vfio_ccw_drv.c
> +++ b/drivers/s390/cio/vfio_ccw_drv.c
> @@ -112,7 +112,7 @@ void vfio_ccw_sch_io_todo(struct work_struct *work)
>                 private->state = VFIO_CCW_STATE_IDLE;
>
>         if (private->io_trigger)
> -               eventfd_signal(private->io_trigger, 1);
> +               eventfd_signal(private->io_trigger);
>  }
>
>  void vfio_ccw_crw_todo(struct work_struct *work)
> @@ -122,7 +122,7 @@ void vfio_ccw_crw_todo(struct work_struct *work)
>         private = container_of(work, struct vfio_ccw_private, crw_work);
>
>         if (!list_empty(&private->crw) && private->crw_trigger)
> -               eventfd_signal(private->crw_trigger, 1);
> +               eventfd_signal(private->crw_trigger);
>  }
>
>  /*
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index cba4971618ff..ea532a8a4a0c 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -421,7 +421,7 @@ static int vfio_ccw_mdev_set_irqs(struct vfio_ccw_private *private,
>         case VFIO_IRQ_SET_DATA_NONE:
>         {
>                 if (*ctx)
> -                       eventfd_signal(*ctx, 1);
> +                       eventfd_signal(*ctx);
>                 return 0;
>         }
>         case VFIO_IRQ_SET_DATA_BOOL:
> @@ -432,7 +432,7 @@ static int vfio_ccw_mdev_set_irqs(struct vfio_ccw_private *private,
>                         return -EFAULT;
>
>                 if (trigger && *ctx)
> -                       eventfd_signal(*ctx, 1);
> +                       eventfd_signal(*ctx);
>                 return 0;
>         }
>         case VFIO_IRQ_SET_DATA_EVENTFD:
> @@ -612,7 +612,7 @@ static void vfio_ccw_mdev_request(struct vfio_device *vdev, unsigned int count)
>                                                "Relaying device request to user (#%u)\n",
>                                                count);
>
> -               eventfd_signal(private->req_trigger, 1);
> +               eventfd_signal(private->req_trigger);
>         } else if (count == 0) {
>                 dev_notice(dev,
>                            "No device request channel registered, blocked until released by user\n");
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 4db538a55192..542b5be73a6a 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -1794,7 +1794,7 @@ static void vfio_ap_mdev_request(struct vfio_device *vdev, unsigned int count)
>                                                "Relaying device request to user (#%u)\n",
>                                                count);
>
> -               eventfd_signal(matrix_mdev->req_trigger, 1);
> +               eventfd_signal(matrix_mdev->req_trigger);
>         } else if (count == 0) {
>                 dev_notice(dev,
>                            "No device request registered, blocked until released by user\n");
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index efe3e3b85769..fdd0fc7b8f25 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -831,7 +831,7 @@ static void ffs_user_copy_worker(struct work_struct *work)
>         io_data->kiocb->ki_complete(io_data->kiocb, ret);
>
>         if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
> -               eventfd_signal(io_data->ffs->ffs_eventfd, 1);
> +               eventfd_signal(io_data->ffs->ffs_eventfd);
>
>         if (io_data->read)
>                 kfree(io_data->to_free);
> @@ -2738,7 +2738,7 @@ static void __ffs_event_add(struct ffs_data *ffs,
>         ffs->ev.types[ffs->ev.count++] = type;
>         wake_up_locked(&ffs->ev.waitq);
>         if (ffs->ffs_eventfd)
> -               eventfd_signal(ffs->ffs_eventfd, 1);
> +               eventfd_signal(ffs->ffs_eventfd);
>  }
>
>  static void ffs_event_add(struct ffs_data *ffs,
> diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
> index 0ddd4b8abecb..6cb5ce4a8b9a 100644
> --- a/drivers/vdpa/vdpa_user/vduse_dev.c
> +++ b/drivers/vdpa/vdpa_user/vduse_dev.c
> @@ -493,7 +493,7 @@ static void vduse_vq_kick(struct vduse_virtqueue *vq)
>                 goto unlock;
>
>         if (vq->kickfd)
> -               eventfd_signal(vq->kickfd, 1);
> +               eventfd_signal(vq->kickfd);
>         else
>                 vq->kicked = true;
>  unlock:
> @@ -911,7 +911,7 @@ static int vduse_kickfd_setup(struct vduse_dev *dev,
>                 eventfd_ctx_put(vq->kickfd);
>         vq->kickfd = ctx;
>         if (vq->ready && vq->kicked && vq->kickfd) {
> -               eventfd_signal(vq->kickfd, 1);
> +               eventfd_signal(vq->kickfd);
>                 vq->kicked = false;
>         }
>         spin_unlock(&vq->kick_lock);
> @@ -960,7 +960,7 @@ static bool vduse_vq_signal_irqfd(struct vduse_virtqueue *vq)
>
>         spin_lock_irq(&vq->irq_lock);
>         if (vq->ready && vq->cb.trigger) {
> -               eventfd_signal(vq->cb.trigger, 1);
> +               eventfd_signal(vq->cb.trigger);
>                 signal = true;
>         }
>         spin_unlock_irq(&vq->irq_lock);
> diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> index c51229fccbd6..d62fbfff20b8 100644
> --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
> @@ -54,7 +54,7 @@ static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
>  {
>         struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
>
> -       eventfd_signal(mc_irq->trigger, 1);
> +       eventfd_signal(mc_irq->trigger);
>         return IRQ_HANDLED;
>  }
>
> diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
> index 1929103ee59a..1cbc990d42e0 100644
> --- a/drivers/vfio/pci/vfio_pci_core.c
> +++ b/drivers/vfio/pci/vfio_pci_core.c
> @@ -443,7 +443,7 @@ static int vfio_pci_core_runtime_resume(struct device *dev)
>          */
>         down_write(&vdev->memory_lock);
>         if (vdev->pm_wake_eventfd_ctx) {
> -               eventfd_signal(vdev->pm_wake_eventfd_ctx, 1);
> +               eventfd_signal(vdev->pm_wake_eventfd_ctx);
>                 __vfio_pci_runtime_pm_exit(vdev);
>         }
>         up_write(&vdev->memory_lock);
> @@ -1883,7 +1883,7 @@ void vfio_pci_core_request(struct vfio_device *core_vdev, unsigned int count)
>                         pci_notice_ratelimited(pdev,
>                                 "Relaying device request to user (#%u)\n",
>                                 count);
> -               eventfd_signal(vdev->req_trigger, 1);
> +               eventfd_signal(vdev->req_trigger);
>         } else if (count == 0) {
>                 pci_warn(pdev,
>                         "No device request channel registered, blocked until released by user\n");
> @@ -2302,7 +2302,7 @@ pci_ers_result_t vfio_pci_core_aer_err_detected(struct pci_dev *pdev,
>         mutex_lock(&vdev->igate);
>
>         if (vdev->err_trigger)
> -               eventfd_signal(vdev->err_trigger, 1);
> +               eventfd_signal(vdev->err_trigger);
>
>         mutex_unlock(&vdev->igate);
>
> diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
> index cbb4bcbfbf83..237beac83809 100644
> --- a/drivers/vfio/pci/vfio_pci_intrs.c
> +++ b/drivers/vfio/pci/vfio_pci_intrs.c
> @@ -94,7 +94,7 @@ static void vfio_send_intx_eventfd(void *opaque, void *unused)
>                 ctx = vfio_irq_ctx_get(vdev, 0);
>                 if (WARN_ON_ONCE(!ctx))
>                         return;
> -               eventfd_signal(ctx->trigger, 1);
> +               eventfd_signal(ctx->trigger);
>         }
>  }
>
> @@ -342,7 +342,7 @@ static irqreturn_t vfio_msihandler(int irq, void *arg)
>  {
>         struct eventfd_ctx *trigger = arg;
>
> -       eventfd_signal(trigger, 1);
> +       eventfd_signal(trigger);
>         return IRQ_HANDLED;
>  }
>
> @@ -689,11 +689,11 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_core_device *vdev,
>                 if (!ctx)
>                         continue;
>                 if (flags & VFIO_IRQ_SET_DATA_NONE) {
> -                       eventfd_signal(ctx->trigger, 1);
> +                       eventfd_signal(ctx->trigger);
>                 } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
>                         uint8_t *bools = data;
>                         if (bools[i - start])
> -                               eventfd_signal(ctx->trigger, 1);
> +                               eventfd_signal(ctx->trigger);
>                 }
>         }
>         return 0;
> @@ -707,7 +707,7 @@ static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
>         if (flags & VFIO_IRQ_SET_DATA_NONE) {
>                 if (*ctx) {
>                         if (count) {
> -                               eventfd_signal(*ctx, 1);
> +                               eventfd_signal(*ctx);
>                         } else {
>                                 eventfd_ctx_put(*ctx);
>                                 *ctx = NULL;
> @@ -722,7 +722,7 @@ static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
>
>                 trigger = *(uint8_t *)data;
>                 if (trigger && *ctx)
> -                       eventfd_signal(*ctx, 1);
> +                       eventfd_signal(*ctx);
>
>                 return 0;
>         } else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
> diff --git a/drivers/vfio/platform/vfio_platform_irq.c b/drivers/vfio/platform/vfio_platform_irq.c
> index 665197caed89..61a1bfb68ac7 100644
> --- a/drivers/vfio/platform/vfio_platform_irq.c
> +++ b/drivers/vfio/platform/vfio_platform_irq.c
> @@ -155,7 +155,7 @@ static irqreturn_t vfio_automasked_irq_handler(int irq, void *dev_id)
>         spin_unlock_irqrestore(&irq_ctx->lock, flags);
>
>         if (ret == IRQ_HANDLED)
> -               eventfd_signal(irq_ctx->trigger, 1);
> +               eventfd_signal(irq_ctx->trigger);
>
>         return ret;
>  }
> @@ -164,7 +164,7 @@ static irqreturn_t vfio_irq_handler(int irq, void *dev_id)
>  {
>         struct vfio_platform_irq *irq_ctx = dev_id;
>
> -       eventfd_signal(irq_ctx->trigger, 1);
> +       eventfd_signal(irq_ctx->trigger);
>
>         return IRQ_HANDLED;
>  }
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 30df5c58db73..8d9f958946d6 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -178,7 +178,7 @@ static irqreturn_t vhost_vdpa_virtqueue_cb(void *private)
>         struct eventfd_ctx *call_ctx = vq->call_ctx.ctx;
>
>         if (call_ctx)
> -               eventfd_signal(call_ctx, 1);
> +               eventfd_signal(call_ctx);
>
>         return IRQ_HANDLED;
>  }
> @@ -189,7 +189,7 @@ static irqreturn_t vhost_vdpa_config_cb(void *private)
>         struct eventfd_ctx *config_ctx = v->config_ctx;
>
>         if (config_ctx)
> -               eventfd_signal(config_ctx, 1);
> +               eventfd_signal(config_ctx);
>
>         return IRQ_HANDLED;
>  }
> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
> index e0c181ad17e3..045f666b4f12 100644
> --- a/drivers/vhost/vhost.c
> +++ b/drivers/vhost/vhost.c
> @@ -2248,7 +2248,7 @@ int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
>                 len -= l;
>                 if (!len) {
>                         if (vq->log_ctx)
> -                               eventfd_signal(vq->log_ctx, 1);
> +                               eventfd_signal(vq->log_ctx);
>                         return 0;
>                 }
>         }
> @@ -2271,7 +2271,7 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq)
>                 log_used(vq, (used - (void __user *)vq->used),
>                          sizeof vq->used->flags);
>                 if (vq->log_ctx)
> -                       eventfd_signal(vq->log_ctx, 1);
> +                       eventfd_signal(vq->log_ctx);
>         }
>         return 0;
>  }
> @@ -2289,7 +2289,7 @@ static int vhost_update_avail_event(struct vhost_virtqueue *vq)
>                 log_used(vq, (used - (void __user *)vq->used),
>                          sizeof *vhost_avail_event(vq));
>                 if (vq->log_ctx)
> -                       eventfd_signal(vq->log_ctx, 1);
> +                       eventfd_signal(vq->log_ctx);
>         }
>         return 0;
>  }
> @@ -2715,7 +2715,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
>                 log_used(vq, offsetof(struct vring_used, idx),
>                          sizeof vq->used->idx);
>                 if (vq->log_ctx)
> -                       eventfd_signal(vq->log_ctx, 1);
> +                       eventfd_signal(vq->log_ctx);
>         }
>         return r;
>  }
> @@ -2763,7 +2763,7 @@ void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
>  {
>         /* Signal the Guest tell them we used something up. */
>         if (vq->call_ctx.ctx && vhost_notify(dev, vq))
> -               eventfd_signal(vq->call_ctx.ctx, 1);
> +               eventfd_signal(vq->call_ctx.ctx);
>  }
>  EXPORT_SYMBOL_GPL(vhost_signal);
>
> diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
> index f60d5f7bef94..9e942fcda5c3 100644
> --- a/drivers/vhost/vhost.h
> +++ b/drivers/vhost/vhost.h
> @@ -249,7 +249,7 @@ void vhost_iotlb_map_free(struct vhost_iotlb *iotlb,
>  #define vq_err(vq, fmt, ...) do {                                  \
>                 pr_debug(pr_fmt(fmt), ##__VA_ARGS__);       \
>                 if ((vq)->error_ctx)                               \
> -                               eventfd_signal((vq)->error_ctx, 1);\
> +                               eventfd_signal((vq)->error_ctx);\
>         } while (0)
>
>  enum {
> diff --git a/drivers/virt/acrn/ioeventfd.c b/drivers/virt/acrn/ioeventfd.c
> index ac4037e9f947..4e845c6ca0b5 100644
> --- a/drivers/virt/acrn/ioeventfd.c
> +++ b/drivers/virt/acrn/ioeventfd.c
> @@ -223,7 +223,7 @@ static int acrn_ioeventfd_handler(struct acrn_ioreq_client *client,
>         mutex_lock(&client->vm->ioeventfds_lock);
>         p = hsm_ioeventfd_match(client->vm, addr, val, size, req->type);
>         if (p)
> -               eventfd_signal(p->eventfd, 1);
> +               eventfd_signal(p->eventfd);
>         mutex_unlock(&client->vm->ioeventfds_lock);
>
>         return 0;
> diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
> index 1ce7f3c7a950..7efc0c62e984 100644
> --- a/drivers/xen/privcmd.c
> +++ b/drivers/xen/privcmd.c
> @@ -1147,7 +1147,7 @@ static irqreturn_t ioeventfd_interrupt(int irq, void *dev_id)
>                 if (ioreq->addr == kioeventfd->addr + VIRTIO_MMIO_QUEUE_NOTIFY &&
>                     ioreq->size == kioeventfd->addr_len &&
>                     (ioreq->data & QUEUE_NOTIFY_VQ_MASK) == kioeventfd->vq) {
> -                       eventfd_signal(kioeventfd->eventfd, 1);
> +                       eventfd_signal(kioeventfd->eventfd);
>                         state = STATE_IORESP_READY;
>                         break;
>                 }
> diff --git a/fs/aio.c b/fs/aio.c
> index f8589caef9c1..5c5b09e52d75 100644
> --- a/fs/aio.c
> +++ b/fs/aio.c
> @@ -1166,7 +1166,7 @@ static void aio_complete(struct aio_kiocb *iocb)
>          * from IRQ context.
>          */
>         if (iocb->ki_eventfd)
> -               eventfd_signal(iocb->ki_eventfd, 1);
> +               eventfd_signal(iocb->ki_eventfd);
>
>         /*
>          * We have to order our ring_info tail store above and test
> diff --git a/fs/eventfd.c b/fs/eventfd.c
> index 33a918f9566c..dc9e01053235 100644
> --- a/fs/eventfd.c
> +++ b/fs/eventfd.c
> @@ -74,20 +74,17 @@ __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask)
>  /**
>   * eventfd_signal - Adds @n to the eventfd counter.
>   * @ctx: [in] Pointer to the eventfd context.
> - * @n: [in] Value of the counter to be added to the eventfd internal counter.
> - *          The value cannot be negative.
>   *
>   * This function is supposed to be called by the kernel in paths that do not
>   * allow sleeping. In this function we allow the counter to reach the ULLONG_MAX
>   * value, and we signal this as overflow condition by returning a EPOLLERR
>   * to poll(2).
>   *
> - * Returns the amount by which the counter was incremented.  This will be less
> - * than @n if the counter has overflowed.
> + * Returns the amount by which the counter was incremented.
>   */
> -__u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n)
> +__u64 eventfd_signal(struct eventfd_ctx *ctx)
>  {
> -       return eventfd_signal_mask(ctx, n, 0);
> +       return eventfd_signal_mask(ctx, 1, 0);
>  }
>  EXPORT_SYMBOL_GPL(eventfd_signal);
>
> diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
> index b9d83652c097..562089431551 100644
> --- a/include/linux/eventfd.h
> +++ b/include/linux/eventfd.h
> @@ -35,7 +35,7 @@ void eventfd_ctx_put(struct eventfd_ctx *ctx);
>  struct file *eventfd_fget(int fd);
>  struct eventfd_ctx *eventfd_ctx_fdget(int fd);
>  struct eventfd_ctx *eventfd_ctx_fileget(struct file *file);
> -__u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n);
> +__u64 eventfd_signal(struct eventfd_ctx *ctx);
>  __u64 eventfd_signal_mask(struct eventfd_ctx *ctx, __u64 n, __poll_t mask);
>  int eventfd_ctx_remove_wait_queue(struct eventfd_ctx *ctx, wait_queue_entry_t *wait,
>                                   __u64 *cnt);
> @@ -58,7 +58,7 @@ static inline struct eventfd_ctx *eventfd_ctx_fdget(int fd)
>         return ERR_PTR(-ENOSYS);
>  }
>
> -static inline int eventfd_signal(struct eventfd_ctx *ctx, __u64 n)
> +static inline int eventfd_signal(struct eventfd_ctx *ctx)
>  {
>         return -ENOSYS;
>  }
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 774bd6e21e27..dfbb1d3b77b7 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -4378,7 +4378,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
>          * only one element of the array here.
>          */
>         for (; i >= 0 && unlikely(t->entries[i].threshold > usage); i--)
> -               eventfd_signal(t->entries[i].eventfd, 1);
> +               eventfd_signal(t->entries[i].eventfd);
>
>         /* i = current_threshold + 1 */
>         i++;
> @@ -4390,7 +4390,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
>          * only one element of the array here.
>          */
>         for (; i < t->size && unlikely(t->entries[i].threshold <= usage); i++)
> -               eventfd_signal(t->entries[i].eventfd, 1);
> +               eventfd_signal(t->entries[i].eventfd);
>
>         /* Update current_threshold */
>         t->current_threshold = i - 1;
> @@ -4430,7 +4430,7 @@ static int mem_cgroup_oom_notify_cb(struct mem_cgroup *memcg)
>         spin_lock(&memcg_oom_lock);
>
>         list_for_each_entry(ev, &memcg->oom_notify, list)
> -               eventfd_signal(ev->eventfd, 1);
> +               eventfd_signal(ev->eventfd);
>
>         spin_unlock(&memcg_oom_lock);
>         return 0;
> @@ -4649,7 +4649,7 @@ static int mem_cgroup_oom_register_event(struct mem_cgroup *memcg,
>
>         /* already in OOM ? */
>         if (memcg->under_oom)
> -               eventfd_signal(eventfd, 1);
> +               eventfd_signal(eventfd);
>         spin_unlock(&memcg_oom_lock);
>
>         return 0;
> @@ -4941,7 +4941,7 @@ static void memcg_event_remove(struct work_struct *work)
>         event->unregister_event(memcg, event->eventfd);
>
>         /* Notify userspace the event is going away. */
> -       eventfd_signal(event->eventfd, 1);
> +       eventfd_signal(event->eventfd);
>
>         eventfd_ctx_put(event->eventfd);
>         kfree(event);
> diff --git a/mm/vmpressure.c b/mm/vmpressure.c
> index 22c6689d9302..bd5183dfd879 100644
> --- a/mm/vmpressure.c
> +++ b/mm/vmpressure.c
> @@ -169,7 +169,7 @@ static bool vmpressure_event(struct vmpressure *vmpr,
>                         continue;
>                 if (level < ev->level)
>                         continue;
> -               eventfd_signal(ev->efd, 1);
> +               eventfd_signal(ev->efd);
>                 ret = true;
>         }
>         mutex_unlock(&vmpr->events_lock);
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index 69ba0281f9e0..2284b3751240 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -234,10 +234,10 @@ static void mtty_trigger_interrupt(struct mdev_state *mdev_state)
>
>         if (is_msi(mdev_state)) {
>                 if (mdev_state->msi_evtfd)
> -                       eventfd_signal(mdev_state->msi_evtfd, 1);
> +                       eventfd_signal(mdev_state->msi_evtfd);
>         } else if (is_intx(mdev_state)) {
>                 if (mdev_state->intx_evtfd && !mdev_state->intx_mask) {
> -                       eventfd_signal(mdev_state->intx_evtfd, 1);
> +                       eventfd_signal(mdev_state->intx_evtfd);
>                         mdev_state->intx_mask = true;
>                 }
>         }
> diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
> index 89912a17f5d5..c0e230f4c3e9 100644
> --- a/virt/kvm/eventfd.c
> +++ b/virt/kvm/eventfd.c
> @@ -61,7 +61,7 @@ static void irqfd_resampler_notify(struct kvm_kernel_irqfd_resampler *resampler)
>
>         list_for_each_entry_srcu(irqfd, &resampler->list, resampler_link,
>                                  srcu_read_lock_held(&resampler->kvm->irq_srcu))
> -               eventfd_signal(irqfd->resamplefd, 1);
> +               eventfd_signal(irqfd->resamplefd);
>  }
>
>  /*
> @@ -786,7 +786,7 @@ ioeventfd_write(struct kvm_vcpu *vcpu, struct kvm_io_device *this, gpa_t addr,
>         if (!ioeventfd_in_range(p, addr, len, val))
>                 return -EOPNOTSUPP;
>
> -       eventfd_signal(p->eventfd, 1);
> +       eventfd_signal(p->eventfd);
>         return 0;
>  }
>
>
> --
> 2.42.0
>
>