From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zhu, Lingshan" Subject: Re: [PATCH V2 1/6] vhost: introduce vhost_call_ctx Date: Mon, 20 Jul 2020 15:40:13 +0800 Message-ID: References: <1594898629-18790-1-git-send-email-lingshan.zhu@intel.com> <1594898629-18790-2-git-send-email-lingshan.zhu@intel.com> <871ee1c1-8cf7-3d9d-1892-5991b92e5db3@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <871ee1c1-8cf7-3d9d-1892-5991b92e5db3@redhat.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org To: Jason Wang , mst@redhat.com, alex.williamson@redhat.com, pbonzini@redhat.com, sean.j.christopherson@intel.com, wanpengli@tencent.com Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org List-Id: virtualization@lists.linuxfoundation.org On 7/17/2020 11:32 AM, Jason Wang wrote: > > On 2020/7/16 下午7:23, Zhu Lingshan wrote: >> This commit introduces struct vhost_call_ctx which replaced >> raw struct eventfd_ctx *call_ctx in struct vhost_virtqueue. >> Besides eventfd_ctx, it contains a spin lock and an >> irq_bypass_producer in its structure. >> >> Signed-off-by: Zhu Lingshan >> Suggested-by: Jason Wang >> --- >>   drivers/vhost/vdpa.c  |  4 ++-- >>   drivers/vhost/vhost.c | 22 ++++++++++++++++------ >>   drivers/vhost/vhost.h |  9 ++++++++- >>   3 files changed, 26 insertions(+), 9 deletions(-) >> >> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c >> index 7580e34..2fcc422 100644 >> --- a/drivers/vhost/vdpa.c >> +++ b/drivers/vhost/vdpa.c >> @@ -96,7 +96,7 @@ static void handle_vq_kick(struct vhost_work *work) >>   static irqreturn_t vhost_vdpa_virtqueue_cb(void *private) >>   { >>       struct vhost_virtqueue *vq = private; >> -    struct eventfd_ctx *call_ctx = vq->call_ctx; >> +    struct eventfd_ctx *call_ctx = vq->call_ctx.ctx; >>         if (call_ctx) >>           eventfd_signal(call_ctx, 1); >> @@ -382,7 +382,7 @@ static long vhost_vdpa_vring_ioctl(struct >> vhost_vdpa *v, unsigned int cmd, >>           break; >>         case VHOST_SET_VRING_CALL: >> -        if (vq->call_ctx) { >> +        if (vq->call_ctx.ctx) { >>               cb.callback = vhost_vdpa_virtqueue_cb; >>               cb.private = vq; >>           } else { >> diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c >> index d7b8df3..4004e94 100644 >> --- a/drivers/vhost/vhost.c >> +++ b/drivers/vhost/vhost.c >> @@ -298,6 +298,13 @@ static void vhost_vq_meta_reset(struct vhost_dev >> *d) >>           __vhost_vq_meta_reset(d->vqs[i]); >>   } >>   +static void vhost_call_ctx_reset(struct vhost_call_ctx *call_ctx) >> +{ >> +    call_ctx->ctx = NULL; >> +    memset(&call_ctx->producer, 0x0, sizeof(struct >> irq_bypass_producer)); >> +    spin_lock_init(&call_ctx->ctx_lock); >> +} >> + >>   static void vhost_vq_reset(struct vhost_dev *dev, >>                  struct vhost_virtqueue *vq) >>   { >> @@ -319,13 +326,13 @@ static void vhost_vq_reset(struct vhost_dev *dev, >>       vq->log_base = NULL; >>       vq->error_ctx = NULL; >>       vq->kick = NULL; >> -    vq->call_ctx = NULL; >>       vq->log_ctx = NULL; >>       vhost_reset_is_le(vq); >>       vhost_disable_cross_endian(vq); >>       vq->busyloop_timeout = 0; >>       vq->umem = NULL; >>       vq->iotlb = NULL; >> +    vhost_call_ctx_reset(&vq->call_ctx); >>       __vhost_vq_meta_reset(vq); >>   } >>   @@ -685,8 +692,8 @@ void vhost_dev_cleanup(struct vhost_dev *dev) >> eventfd_ctx_put(dev->vqs[i]->error_ctx); >>           if (dev->vqs[i]->kick) >>               fput(dev->vqs[i]->kick); >> -        if (dev->vqs[i]->call_ctx) >> - eventfd_ctx_put(dev->vqs[i]->call_ctx); >> +        if (dev->vqs[i]->call_ctx.ctx) >> + eventfd_ctx_put(dev->vqs[i]->call_ctx.ctx); >>           vhost_vq_reset(dev, dev->vqs[i]); >>       } >>       vhost_dev_free_iovecs(dev); >> @@ -1629,7 +1636,10 @@ long vhost_vring_ioctl(struct vhost_dev *d, >> unsigned int ioctl, void __user *arg >>               r = PTR_ERR(ctx); >>               break; >>           } >> -        swap(ctx, vq->call_ctx); >> + >> +        spin_lock(&vq->call_ctx.ctx_lock); >> +        swap(ctx, vq->call_ctx.ctx); >> +        spin_unlock(&vq->call_ctx.ctx_lock); >>           break; >>       case VHOST_SET_VRING_ERR: >>           if (copy_from_user(&f, argp, sizeof f)) { >> @@ -2440,8 +2450,8 @@ static bool vhost_notify(struct vhost_dev *dev, >> struct vhost_virtqueue *vq) >>   void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) >>   { >>       /* Signal the Guest tell them we used something up. */ >> -    if (vq->call_ctx && vhost_notify(dev, vq)) >> -        eventfd_signal(vq->call_ctx, 1); >> +    if (vq->call_ctx.ctx && vhost_notify(dev, vq)) >> +        eventfd_signal(vq->call_ctx.ctx, 1); >>   } >>   EXPORT_SYMBOL_GPL(vhost_signal); >>   diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h >> index c8e96a0..402c62e 100644 >> --- a/drivers/vhost/vhost.h >> +++ b/drivers/vhost/vhost.h >> @@ -13,6 +13,7 @@ >>   #include >>   #include >>   #include >> +#include >>     struct vhost_work; >>   typedef void (*vhost_work_fn_t)(struct vhost_work *work); >> @@ -60,6 +61,12 @@ enum vhost_uaddr_type { >>       VHOST_NUM_ADDRS = 3, >>   }; >>   +struct vhost_call_ctx { > > > I think maybe "vhost_vring_call" is a better name since it contains > not only the eventfd_ctx now. > > Thanks Sure > > >> +    struct eventfd_ctx *ctx; >> +    struct irq_bypass_producer producer; >> +    spinlock_t ctx_lock; >> +}; >> + >>   /* The virtqueue structure describes a queue attached to a device. */ >>   struct vhost_virtqueue { >>       struct vhost_dev *dev; >> @@ -72,7 +79,7 @@ struct vhost_virtqueue { >>       vring_used_t __user *used; >>       const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS]; >>       struct file *kick; >> -    struct eventfd_ctx *call_ctx; >> +    struct vhost_call_ctx call_ctx; >>       struct eventfd_ctx *error_ctx; >>       struct eventfd_ctx *log_ctx; >