From patchwork Wed Jun 10 11:35:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217862 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6CB7AC433E0 for ; Wed, 10 Jun 2020 11:38:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43AEC2074B for ; Wed, 10 Jun 2020 11:38:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OQICKjA6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728582AbgFJLgH (ORCPT ); Wed, 10 Jun 2020 07:36:07 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:42894 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728532AbgFJLgG (ORCPT ); Wed, 10 Jun 2020 07:36:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788963; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pyZgoc1IoaMWB9Jefr7e/GoAFJJxo7imj3dgpBB/etA=; b=OQICKjA6nnej0HMupGEjUl+weYxV7y3Wci70Bp8LLiZPzh78PygxtjdHXBuiwV4uTJl5Hf fe46ggq1U+2fODx8ZAAkLr82IeBCdRZ9GmJ3B7ydU9oQWG7BV9gdUtjX9+wW7MKsSHvcp6 fn+P5aPRQ4hISEv8Z6FIljgvU8oOQ30= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-148-TbrJuia5Ox63Gp9XVyEewQ-1; Wed, 10 Jun 2020 07:36:01 -0400 X-MC-Unique: TbrJuia5Ox63Gp9XVyEewQ-1 Received: by mail-wm1-f70.google.com with SMTP id p24so332669wma.4 for ; Wed, 10 Jun 2020 04:36:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=pyZgoc1IoaMWB9Jefr7e/GoAFJJxo7imj3dgpBB/etA=; b=Gri8j0i4S7ReltNOFBO1LIcDlPNAJmvCQg2znuR/9doaRmdGmmB1YPrqAoJJwCsst2 +5CR6dkac9mrVxlhi0aZLBMeU2/xRCFFUiVzmJZjLpBo+t8jYH9vXoMJdPp2C2phmThq FuJE6OiEhzbxDZ/MqS2m2xF8rjAxLkPY2+SLDJy0/UAKVdmQ3Z3fL0dO8eXjCnOB520l sZG1U4sxMxqGm/669t9XRgRIkzvWZHg6VJGaDPLWpNpBzObHM26oxXZREhHpcJJwwBQi OwuotvoCaVkjcog+Xxq82+jKbaidiui08FcHBqOJS/FYFEBeatR+6JHGbOrrJ/9i4SAZ AkKg== X-Gm-Message-State: AOAM531gN1QubHOpaHZWE/HrX63TO3HyhItnUSiEizXc4hOcx2YkI2Y1 qQ/OV/DrSruAl1TDycAmbGEKmr+BQI4hlXm9ZCAsKSNuEpVJjOHuEbJes5WwjaX5AEI5i7Eu1gF MDaqj0cugZzP1A9bI X-Received: by 2002:adf:bbc5:: with SMTP id z5mr3253348wrg.269.1591788959997; Wed, 10 Jun 2020 04:35:59 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxRnisEyiSe77VgOXdspneG3+R5Whgn51TWUKnQmdwoU0/5KTvFQ8dV5mziKKbguFJ0mnBDtQ== X-Received: by 2002:adf:bbc5:: with SMTP id z5mr3253304wrg.269.1591788959418; Wed, 10 Jun 2020 04:35:59 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id j5sm7713166wrq.39.2020.06.10.04.35.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:35:49 -0700 (PDT) Date: Wed, 10 Jun 2020 07:35:47 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 01/14] vhost: option to fetch descriptors through an independent struct Message-ID: <20200610113515.1497099-2-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The idea is to support multiple ring formats by converting to a format-independent array of descriptors. This costs extra cycles, but we gain in ability to fetch a batch of descriptors in one go, which is good for code cache locality. When used, this causes a minor performance degradation, it's been kept as simple as possible for ease of review. A follow-up patch gets us back the performance by adding batching. To simplify benchmarking, I kept the old code around so one can switch back and forth between old and new code. This will go away in the final submission. Signed-off-by: Michael S. Tsirkin Signed-off-by: Eugenio Pérez Link: https://lore.kernel.org/r/20200401183118.8334-2-eperezma@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 305 +++++++++++++++++++++++++++++++++++++++++- drivers/vhost/vhost.h | 16 +++ 2 files changed, 320 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 172da092107e..180b7b58c76b 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -303,6 +303,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, struct vhost_virtqueue *vq) { vq->num = 1; + vq->ndescs = 0; vq->desc = NULL; vq->avail = NULL; vq->used = NULL; @@ -373,6 +374,9 @@ static int vhost_worker(void *data) static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq) { + kfree(vq->descs); + vq->descs = NULL; + vq->max_descs = 0; kfree(vq->indirect); vq->indirect = NULL; kfree(vq->log); @@ -389,6 +393,10 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; + vq->max_descs = dev->iov_limit; + vq->descs = kmalloc_array(vq->max_descs, + sizeof(*vq->descs), + GFP_KERNEL); vq->indirect = kmalloc_array(UIO_MAXIOV, sizeof(*vq->indirect), GFP_KERNEL); @@ -396,7 +404,7 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) GFP_KERNEL); vq->heads = kmalloc_array(dev->iov_limit, sizeof(*vq->heads), GFP_KERNEL); - if (!vq->indirect || !vq->log || !vq->heads) + if (!vq->indirect || !vq->log || !vq->heads || !vq->descs) goto err_nomem; } return 0; @@ -488,6 +496,8 @@ void vhost_dev_init(struct vhost_dev *dev, for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; + vq->descs = NULL; + vq->max_descs = 0; vq->log = NULL; vq->indirect = NULL; vq->heads = NULL; @@ -2315,6 +2325,299 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, } EXPORT_SYMBOL_GPL(vhost_get_vq_desc); +static struct vhost_desc *peek_split_desc(struct vhost_virtqueue *vq) +{ + BUG_ON(!vq->ndescs); + return &vq->descs[vq->ndescs - 1]; +} + +static void pop_split_desc(struct vhost_virtqueue *vq) +{ + BUG_ON(!vq->ndescs); + --vq->ndescs; +} + +#define VHOST_DESC_FLAGS (VRING_DESC_F_INDIRECT | VRING_DESC_F_WRITE | \ + VRING_DESC_F_NEXT) +static int push_split_desc(struct vhost_virtqueue *vq, struct vring_desc *desc, u16 id) +{ + struct vhost_desc *h; + + if (unlikely(vq->ndescs >= vq->max_descs)) + return -EINVAL; + h = &vq->descs[vq->ndescs++]; + h->addr = vhost64_to_cpu(vq, desc->addr); + h->len = vhost32_to_cpu(vq, desc->len); + h->flags = vhost16_to_cpu(vq, desc->flags) & VHOST_DESC_FLAGS; + h->id = id; + + return 0; +} + +static int fetch_indirect_descs(struct vhost_virtqueue *vq, + struct vhost_desc *indirect, + u16 head) +{ + struct vring_desc desc; + unsigned int i = 0, count, found = 0; + u32 len = indirect->len; + struct iov_iter from; + int ret; + + /* Sanity check */ + if (unlikely(len % sizeof desc)) { + vq_err(vq, "Invalid length in indirect descriptor: " + "len 0x%llx not multiple of 0x%zx\n", + (unsigned long long)len, + sizeof desc); + return -EINVAL; + } + + ret = translate_desc(vq, indirect->addr, len, vq->indirect, + UIO_MAXIOV, VHOST_ACCESS_RO); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d in indirect.\n", ret); + return ret; + } + iov_iter_init(&from, READ, vq->indirect, ret, len); + + /* We will use the result as an address to read from, so most + * architectures only need a compiler barrier here. */ + read_barrier_depends(); + + count = len / sizeof desc; + /* Buffers are chained via a 16 bit next field, so + * we can have at most 2^16 of these. */ + if (unlikely(count > USHRT_MAX + 1)) { + vq_err(vq, "Indirect buffer length too big: %d\n", + indirect->len); + return -E2BIG; + } + if (unlikely(vq->ndescs + count > vq->max_descs)) { + vq_err(vq, "Too many indirect + direct descs: %d + %d\n", + vq->ndescs, indirect->len); + return -E2BIG; + } + + do { + if (unlikely(++found > count)) { + vq_err(vq, "Loop detected: last one at %u " + "indirect size %u\n", + i, count); + return -EINVAL; + } + if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) { + vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", + i, (size_t)indirect->addr + i * sizeof desc); + return -EINVAL; + } + if (unlikely(desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT))) { + vq_err(vq, "Nested indirect descriptor: idx %d, %zx\n", + i, (size_t)indirect->addr + i * sizeof desc); + return -EINVAL; + } + + /* Note: push_split_desc can't fail here: + * we never fetch unless there's space. */ + ret = push_split_desc(vq, &desc, head); + WARN_ON(ret); + } while ((i = next_desc(vq, &desc)) != -1); + return 0; +} + +/* This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ +static int fetch_descs(struct vhost_virtqueue *vq) +{ + unsigned int i, head, found = 0; + struct vhost_desc *last; + struct vring_desc desc; + __virtio16 avail_idx; + __virtio16 ring_head; + u16 last_avail_idx; + int ret; + + /* Check it isn't doing very strange things with descriptor numbers. */ + last_avail_idx = vq->last_avail_idx; + + if (vq->avail_idx == vq->last_avail_idx) { + if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { + vq_err(vq, "Failed to access avail idx at %p\n", + &vq->avail->idx); + return -EFAULT; + } + vq->avail_idx = vhost16_to_cpu(vq, avail_idx); + + if (unlikely((u16)(vq->avail_idx - last_avail_idx) > vq->num)) { + vq_err(vq, "Guest moved used index from %u to %u", + last_avail_idx, vq->avail_idx); + return -EFAULT; + } + + /* If there's nothing new since last we looked, return + * invalid. + */ + if (vq->avail_idx == last_avail_idx) + return 0; + + /* Only get avail ring entries after they have been + * exposed by guest. + */ + smp_rmb(); + } + + /* Grab the next descriptor number they're advertising */ + if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) { + vq_err(vq, "Failed to read head: idx %d address %p\n", + last_avail_idx, + &vq->avail->ring[last_avail_idx % vq->num]); + return -EFAULT; + } + + head = vhost16_to_cpu(vq, ring_head); + + /* If their number is silly, that's an error. */ + if (unlikely(head >= vq->num)) { + vq_err(vq, "Guest says index %u > %u is available", + head, vq->num); + return -EINVAL; + } + + i = head; + do { + if (unlikely(i >= vq->num)) { + vq_err(vq, "Desc index is %u > %u, head = %u", + i, vq->num, head); + return -EINVAL; + } + if (unlikely(++found > vq->num)) { + vq_err(vq, "Loop detected: last one at %u " + "vq size %u head %u\n", + i, vq->num, head); + return -EINVAL; + } + ret = vhost_get_desc(vq, &desc, i); + if (unlikely(ret)) { + vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", + i, vq->desc + i); + return -EFAULT; + } + ret = push_split_desc(vq, &desc, head); + if (unlikely(ret)) { + vq_err(vq, "Failed to save descriptor: idx %d\n", i); + return -EINVAL; + } + } while ((i = next_desc(vq, &desc)) != -1); + + last = peek_split_desc(vq); + if (unlikely(last->flags & VRING_DESC_F_INDIRECT)) { + pop_split_desc(vq); + ret = fetch_indirect_descs(vq, last, head); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Failure detected " + "in indirect descriptor at idx %d\n", head); + return ret; + } + } + + /* Assume notifications from guest are disabled at this point, + * if they aren't we would need to update avail_event index. */ + BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); + + /* On success, increment avail index. */ + vq->last_avail_idx++; + + return 1; +} + +/* This looks in the virtqueue and for the first available buffer, and converts + * it to an iovec for convenient access. Since descriptors consist of some + * number of output then some number of input descriptors, it's actually two + * iovecs, but we pack them into one and note how many of each there were. + * + * This function returns the descriptor number found, or vq->num (which is + * never a valid descriptor number) if none was found. A negative code is + * returned on error. */ +int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, + struct iovec iov[], unsigned int iov_size, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num) +{ + int ret = fetch_descs(vq); + int i; + + if (ret <= 0) + goto err_fetch; + + /* Now convert to IOV */ + /* When we start there are none of either input nor output. */ + *out_num = *in_num = 0; + if (unlikely(log)) + *log_num = 0; + + for (i = 0; i < vq->ndescs; ++i) { + unsigned iov_count = *in_num + *out_num; + struct vhost_desc *desc = &vq->descs[i]; + int access; + + if (desc->flags & ~VHOST_DESC_FLAGS) { + vq_err(vq, "Unexpected flags: 0x%x at descriptor id 0x%x\n", + desc->flags, desc->id); + ret = -EINVAL; + goto err; + } + if (desc->flags & VRING_DESC_F_WRITE) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; + ret = translate_desc(vq, desc->addr, + desc->len, iov + iov_count, + iov_size - iov_count, access); + if (unlikely(ret < 0)) { + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d descriptor idx %d\n", + ret, i); + goto err; + } + if (access == VHOST_ACCESS_WO) { + /* If this is an input descriptor, + * increment that count. */ + *in_num += ret; + if (unlikely(log && ret)) { + log[*log_num].addr = desc->addr; + log[*log_num].len = desc->len; + ++*log_num; + } + } else { + /* If it's an output descriptor, they're all supposed + * to come before any input descriptors. */ + if (unlikely(*in_num)) { + vq_err(vq, "Descriptor has out after in: " + "idx %d\n", i); + ret = -EINVAL; + goto err; + } + *out_num += ret; + } + + ret = desc->id; + } + + vq->ndescs = 0; + + return ret; + +err: + vhost_discard_vq_desc(vq, 1); +err_fetch: + vq->ndescs = 0; + + return ret; +} +EXPORT_SYMBOL_GPL(vhost_get_vq_desc_batch); + /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c8e96a095d3b..87089d51490d 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -60,6 +60,13 @@ enum vhost_uaddr_type { VHOST_NUM_ADDRS = 3, }; +struct vhost_desc { + u64 addr; + u32 len; + u16 flags; /* VRING_DESC_F_WRITE, VRING_DESC_F_NEXT */ + u16 id; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -71,6 +78,11 @@ struct vhost_virtqueue { vring_avail_t __user *avail; vring_used_t __user *used; const struct vhost_iotlb_map *meta_iotlb[VHOST_NUM_ADDRS]; + + struct vhost_desc *descs; + int ndescs; + int max_descs; + struct file *kick; struct eventfd_ctx *call_ctx; struct eventfd_ctx *error_ctx; @@ -177,6 +189,10 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); +int vhost_get_vq_desc_batch(struct vhost_virtqueue *, + struct iovec iov[], unsigned int iov_count, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num); int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, From patchwork Wed Jun 10 11:36:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217863 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9618C433DF for ; Wed, 10 Jun 2020 11:38:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFD072078C for ; Wed, 10 Jun 2020 11:38:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YG3vcIKK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728914AbgFJLiK (ORCPT ); Wed, 10 Jun 2020 07:38:10 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27757 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728590AbgFJLgM (ORCPT ); Wed, 10 Jun 2020 07:36:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788968; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+h6WNjt1EUJ7djnafdeXZVt1l60+nlqYD5MbYj/O2cA=; b=YG3vcIKKyD08vUgtliPZpy3oVzUV1+AjtaWHbGgRkrTsfUZMlUuAhS3zs0QyalR9G3Ckbo 0AOrLWHG/ebTNJpPURfyxX96F3t/DfyndespZEBYlrR7so0c774QX8IaJRVwH0CRSy8ddc tHSkXv19aj7tOrYGIIfBAGhA4ZorqbA= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-219-tafvhpogNsCCV1VyAYLsqQ-1; Wed, 10 Jun 2020 07:36:07 -0400 X-MC-Unique: tafvhpogNsCCV1VyAYLsqQ-1 Received: by mail-wr1-f72.google.com with SMTP id p9so966286wrx.10 for ; Wed, 10 Jun 2020 04:36:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=+h6WNjt1EUJ7djnafdeXZVt1l60+nlqYD5MbYj/O2cA=; b=EmADPgsspkPxc7AK6i+DIKKL4iL2kyRYLmnS3zLASmLbq3dDJcYx+PXKzTyRk98pAG wxHRjA8xL5jP+BOdzhXQGxS8XLRReYU0rVBLWUzDr6evhzfLDAgMscy3c1PjF7GE0TbY c0l6fp/vayCjF5XHHmn/8tnwR8G/JvhnCSYNSLqAZlTMV4Xa83c6rVWi96hOjPahGsU+ RioCDQtjGOWb/6tIiX0ZewPyWWUYfXfJkn6VQbDDY++INrX8mvDTGUzfS3Lo82Z+X7go Gc/0EJ0MtVL/O4XUmoHuToFtTETZwoclPf/z/yr4xQHhy3I1xSq9zaIzUhxlRu0aNXTP qwoA== X-Gm-Message-State: AOAM532eXl2hbS40kcfPd8Wc+7GksQ+MVhkwPQAsxsoT3V6zN/6MQ5fZ edUfGFgjtUwZs/0e1KARnkq1gwoVlzD6r+uPngsGVOvM6bync+AC/Ibg8o9wmsuwQW0FPWXVDTy SfKxcNhPPWOojZzmq X-Received: by 2002:a5d:490f:: with SMTP id x15mr3144242wrq.259.1591788965614; Wed, 10 Jun 2020 04:36:05 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwues+Vtl6aY5DUeDEIDuDb9cULECCZ7k6aJQia4Eyl+dDBLUV4uwB3BChedOa92Aoj6O82sg== X-Received: by 2002:a5d:490f:: with SMTP id x15mr3144193wrq.259.1591788964996; Wed, 10 Jun 2020 04:36:04 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id t14sm8096781wrb.94.2020.06.10.04.36.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:04 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:02 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 03/14] vhost: use batched get_vq_desc version Message-ID: <20200610113515.1497099-4-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As testing shows no performance change, switch to that now. Signed-off-by: Michael S. Tsirkin Signed-off-by: Eugenio Pérez Link: https://lore.kernel.org/r/20200401183118.8334-3-eperezma@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/test.c | 2 +- drivers/vhost/vhost.c | 318 ++++++++---------------------------------- drivers/vhost/vhost.h | 7 +- 3 files changed, 65 insertions(+), 262 deletions(-) diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c index 0466921f4772..7d69778aaa26 100644 --- a/drivers/vhost/test.c +++ b/drivers/vhost/test.c @@ -119,7 +119,7 @@ static int vhost_test_open(struct inode *inode, struct file *f) dev = &n->dev; vqs[VHOST_TEST_VQ] = &n->vqs[VHOST_TEST_VQ]; n->vqs[VHOST_TEST_VQ].handle_kick = handle_vq_kick; - vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX, UIO_MAXIOV, + vhost_dev_init(dev, vqs, VHOST_TEST_VQ_MAX, UIO_MAXIOV + 64, VHOST_TEST_PKT_WEIGHT, VHOST_TEST_WEIGHT, true, NULL); f->private_data = n; diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 11433d709651..28f324fd77df 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -304,6 +304,7 @@ static void vhost_vq_reset(struct vhost_dev *dev, { vq->num = 1; vq->ndescs = 0; + vq->first_desc = 0; vq->desc = NULL; vq->avail = NULL; vq->used = NULL; @@ -372,6 +373,11 @@ static int vhost_worker(void *data) return 0; } +static int vhost_vq_num_batch_descs(struct vhost_virtqueue *vq) +{ + return vq->max_descs - UIO_MAXIOV; +} + static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq) { kfree(vq->descs); @@ -394,6 +400,9 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; vq->max_descs = dev->iov_limit; + if (vhost_vq_num_batch_descs(vq) < 0) { + return -EINVAL; + } vq->descs = kmalloc_array(vq->max_descs, sizeof(*vq->descs), GFP_KERNEL); @@ -1610,6 +1619,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg vq->last_avail_idx = s.num; /* Forget the cached index value. */ vq->avail_idx = vq->last_avail_idx; + vq->ndescs = vq->first_desc = 0; break; case VHOST_GET_VRING_BASE: s.index = idx; @@ -2078,253 +2088,6 @@ static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc) return next; } -static int get_indirect(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num, - struct vring_desc *indirect) -{ - struct vring_desc desc; - unsigned int i = 0, count, found = 0; - u32 len = vhost32_to_cpu(vq, indirect->len); - struct iov_iter from; - int ret, access; - - /* Sanity check */ - if (unlikely(len % sizeof desc)) { - vq_err(vq, "Invalid length in indirect descriptor: " - "len 0x%llx not multiple of 0x%zx\n", - (unsigned long long)len, - sizeof desc); - return -EINVAL; - } - - ret = translate_desc(vq, vhost64_to_cpu(vq, indirect->addr), len, vq->indirect, - UIO_MAXIOV, VHOST_ACCESS_RO); - if (unlikely(ret < 0)) { - if (ret != -EAGAIN) - vq_err(vq, "Translation failure %d in indirect.\n", ret); - return ret; - } - iov_iter_init(&from, READ, vq->indirect, ret, len); - - /* We will use the result as an address to read from, so most - * architectures only need a compiler barrier here. */ - read_barrier_depends(); - - count = len / sizeof desc; - /* Buffers are chained via a 16 bit next field, so - * we can have at most 2^16 of these. */ - if (unlikely(count > USHRT_MAX + 1)) { - vq_err(vq, "Indirect buffer length too big: %d\n", - indirect->len); - return -E2BIG; - } - - do { - unsigned iov_count = *in_num + *out_num; - if (unlikely(++found > count)) { - vq_err(vq, "Loop detected: last one at %u " - "indirect size %u\n", - i, count); - return -EINVAL; - } - if (unlikely(!copy_from_iter_full(&desc, sizeof(desc), &from))) { - vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", - i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); - return -EINVAL; - } - if (unlikely(desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT))) { - vq_err(vq, "Nested indirect descriptor: idx %d, %zx\n", - i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); - return -EINVAL; - } - - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) - access = VHOST_ACCESS_WO; - else - access = VHOST_ACCESS_RO; - - ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), - vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count, access); - if (unlikely(ret < 0)) { - if (ret != -EAGAIN) - vq_err(vq, "Translation failure %d indirect idx %d\n", - ret, i); - return ret; - } - /* If this is an input descriptor, increment that count. */ - if (access == VHOST_ACCESS_WO) { - *in_num += ret; - if (unlikely(log && ret)) { - log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); - log[*log_num].len = vhost32_to_cpu(vq, desc.len); - ++*log_num; - } - } else { - /* If it's an output descriptor, they're all supposed - * to come before any input descriptors. */ - if (unlikely(*in_num)) { - vq_err(vq, "Indirect descriptor " - "has out after in: idx %d\n", i); - return -EINVAL; - } - *out_num += ret; - } - } while ((i = next_desc(vq, &desc)) != -1); - return 0; -} - -/* This looks in the virtqueue and for the first available buffer, and converts - * it to an iovec for convenient access. Since descriptors consist of some - * number of output then some number of input descriptors, it's actually two - * iovecs, but we pack them into one and note how many of each there were. - * - * This function returns the descriptor number found, or vq->num (which is - * never a valid descriptor number) if none was found. A negative code is - * returned on error. */ -int vhost_get_vq_desc(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num) -{ - struct vring_desc desc; - unsigned int i, head, found = 0; - u16 last_avail_idx; - __virtio16 avail_idx; - __virtio16 ring_head; - int ret, access; - - /* Check it isn't doing very strange things with descriptor numbers. */ - last_avail_idx = vq->last_avail_idx; - - if (vq->avail_idx == vq->last_avail_idx) { - if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { - vq_err(vq, "Failed to access avail idx at %p\n", - &vq->avail->idx); - return -EFAULT; - } - vq->avail_idx = vhost16_to_cpu(vq, avail_idx); - - if (unlikely((u16)(vq->avail_idx - last_avail_idx) > vq->num)) { - vq_err(vq, "Guest moved used index from %u to %u", - last_avail_idx, vq->avail_idx); - return -EFAULT; - } - - /* If there's nothing new since last we looked, return - * invalid. - */ - if (vq->avail_idx == last_avail_idx) - return vq->num; - - /* Only get avail ring entries after they have been - * exposed by guest. - */ - smp_rmb(); - } - - /* Grab the next descriptor number they're advertising, and increment - * the index we've seen. */ - if (unlikely(vhost_get_avail_head(vq, &ring_head, last_avail_idx))) { - vq_err(vq, "Failed to read head: idx %d address %p\n", - last_avail_idx, - &vq->avail->ring[last_avail_idx % vq->num]); - return -EFAULT; - } - - head = vhost16_to_cpu(vq, ring_head); - - /* If their number is silly, that's an error. */ - if (unlikely(head >= vq->num)) { - vq_err(vq, "Guest says index %u > %u is available", - head, vq->num); - return -EINVAL; - } - - /* When we start there are none of either input nor output. */ - *out_num = *in_num = 0; - if (unlikely(log)) - *log_num = 0; - - i = head; - do { - unsigned iov_count = *in_num + *out_num; - if (unlikely(i >= vq->num)) { - vq_err(vq, "Desc index is %u > %u, head = %u", - i, vq->num, head); - return -EINVAL; - } - if (unlikely(++found > vq->num)) { - vq_err(vq, "Loop detected: last one at %u " - "vq size %u head %u\n", - i, vq->num, head); - return -EINVAL; - } - ret = vhost_get_desc(vq, &desc, i); - if (unlikely(ret)) { - vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", - i, vq->desc + i); - return -EFAULT; - } - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT)) { - ret = get_indirect(vq, iov, iov_size, - out_num, in_num, - log, log_num, &desc); - if (unlikely(ret < 0)) { - if (ret != -EAGAIN) - vq_err(vq, "Failure detected " - "in indirect descriptor at idx %d\n", i); - return ret; - } - continue; - } - - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) - access = VHOST_ACCESS_WO; - else - access = VHOST_ACCESS_RO; - ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), - vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count, access); - if (unlikely(ret < 0)) { - if (ret != -EAGAIN) - vq_err(vq, "Translation failure %d descriptor idx %d\n", - ret, i); - return ret; - } - if (access == VHOST_ACCESS_WO) { - /* If this is an input descriptor, - * increment that count. */ - *in_num += ret; - if (unlikely(log && ret)) { - log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); - log[*log_num].len = vhost32_to_cpu(vq, desc.len); - ++*log_num; - } - } else { - /* If it's an output descriptor, they're all supposed - * to come before any input descriptors. */ - if (unlikely(*in_num)) { - vq_err(vq, "Descriptor has out after in: " - "idx %d\n", i); - return -EINVAL; - } - *out_num += ret; - } - } while ((i = next_desc(vq, &desc)) != -1); - - /* On success, increment avail index. */ - vq->last_avail_idx++; - - /* Assume notifications from guest are disabled at this point, - * if they aren't we would need to update avail_event index. */ - BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY)); - return head; -} -EXPORT_SYMBOL_GPL(vhost_get_vq_desc); - static struct vhost_desc *peek_split_desc(struct vhost_virtqueue *vq) { BUG_ON(!vq->ndescs); @@ -2428,7 +2191,7 @@ static int fetch_indirect_descs(struct vhost_virtqueue *vq, /* This function returns a value > 0 if a descriptor was found, or 0 if none were found. * A negative code is returned on error. */ -static int fetch_descs(struct vhost_virtqueue *vq) +static int fetch_buf(struct vhost_virtqueue *vq) { unsigned int i, head, found = 0; struct vhost_desc *last; @@ -2441,7 +2204,11 @@ static int fetch_descs(struct vhost_virtqueue *vq) /* Check it isn't doing very strange things with descriptor numbers. */ last_avail_idx = vq->last_avail_idx; - if (vq->avail_idx == vq->last_avail_idx) { + if (unlikely(vq->avail_idx == vq->last_avail_idx)) { + /* If we already have work to do, don't bother re-checking. */ + if (likely(vq->ndescs)) + return 1; + if (unlikely(vhost_get_avail_idx(vq, &avail_idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); @@ -2532,6 +2299,41 @@ static int fetch_descs(struct vhost_virtqueue *vq) return 1; } +/* This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ +static int fetch_descs(struct vhost_virtqueue *vq) +{ + int ret; + + if (unlikely(vq->first_desc >= vq->ndescs)) { + vq->first_desc = 0; + vq->ndescs = 0; + } + + if (vq->ndescs) + return 1; + + for (ret = 1; + ret > 0 && vq->ndescs <= vhost_vq_num_batch_descs(vq); + ret = fetch_buf(vq)) + ; + + /* On success we expect some descs */ + BUG_ON(ret > 0 && !vq->ndescs); + return ret; +} + +/* Reverse the effects of fetch_descs */ +static void unfetch_descs(struct vhost_virtqueue *vq) +{ + int i; + + for (i = vq->first_desc; i < vq->ndescs; ++i) + if (!(vq->descs[i].flags & VRING_DESC_F_NEXT)) + vq->last_avail_idx -= 1; + vq->ndescs = 0; +} + /* This looks in the virtqueue and for the first available buffer, and converts * it to an iovec for convenient access. Since descriptors consist of some * number of output then some number of input descriptors, it's actually two @@ -2540,7 +2342,7 @@ static int fetch_descs(struct vhost_virtqueue *vq) * This function returns the descriptor number found, or vq->num (which is * never a valid descriptor number) if none was found. A negative code is * returned on error. */ -int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, +int vhost_get_vq_desc(struct vhost_virtqueue *vq, struct iovec iov[], unsigned int iov_size, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num) @@ -2549,7 +2351,7 @@ int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, int i; if (ret <= 0) - goto err_fetch; + goto err; /* Now convert to IOV */ /* When we start there are none of either input nor output. */ @@ -2557,7 +2359,7 @@ int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, if (unlikely(log)) *log_num = 0; - for (i = 0; i < vq->ndescs; ++i) { + for (i = vq->first_desc; i < vq->ndescs; ++i) { unsigned iov_count = *in_num + *out_num; struct vhost_desc *desc = &vq->descs[i]; int access; @@ -2603,24 +2405,26 @@ int vhost_get_vq_desc_batch(struct vhost_virtqueue *vq, } ret = desc->id; + + if (!(desc->flags & VRING_DESC_F_NEXT)) + break; } - vq->ndescs = 0; + vq->first_desc = i + 1; return ret; err: - vhost_discard_vq_desc(vq, 1); -err_fetch: - vq->ndescs = 0; + unfetch_descs(vq); return ret ? ret : vq->num; } -EXPORT_SYMBOL_GPL(vhost_get_vq_desc_batch); +EXPORT_SYMBOL_GPL(vhost_get_vq_desc); /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) { + unfetch_descs(vq); vq->last_avail_idx -= n; } EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 87089d51490d..fed36af5c444 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -81,6 +81,7 @@ struct vhost_virtqueue { struct vhost_desc *descs; int ndescs; + int first_desc; int max_descs; struct file *kick; @@ -189,10 +190,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); -int vhost_get_vq_desc_batch(struct vhost_virtqueue *, - struct iovec iov[], unsigned int iov_count, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num); int vhost_get_vq_desc(struct vhost_virtqueue *, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, @@ -261,6 +258,8 @@ static inline void vhost_vq_set_backend(struct vhost_virtqueue *vq, void *private_data) { vq->private_data = private_data; + vq->ndescs = 0; + vq->first_desc = 0; } /** From patchwork Wed Jun 10 11:36:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217864 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18321C433DF for ; Wed, 10 Jun 2020 11:38:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D84362074B for ; Wed, 10 Jun 2020 11:38:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XVN6nOuA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728893AbgFJLiA (ORCPT ); Wed, 10 Jun 2020 07:38:00 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:29141 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728623AbgFJLgR (ORCPT ); Wed, 10 Jun 2020 07:36:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788975; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=+SD3Vrt7U6HArLpzqOyIxuZrc1fS29Ei8HX5xaDKKOw=; b=XVN6nOuA43iDlFdg6LVf7YTxeBwVeeVXzXvw+G8iedVX/pOHO1iIWzeEXjaK31tQhrJef/ YIUwaEjN258AEj3zJlp4aQvHabvoEoJBnKqVQG1kinOz4+8oLnwNKalbdQzfgTs2Vnk/93 hmaT8RtA4P4rOtQSwjkjxpsFeFeyk7U= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-106-sXNWKWbrPZuq7zm72692Lg-1; Wed, 10 Jun 2020 07:36:12 -0400 X-MC-Unique: sXNWKWbrPZuq7zm72692Lg-1 Received: by mail-wr1-f69.google.com with SMTP id r5so968328wrt.9 for ; Wed, 10 Jun 2020 04:36:11 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=+SD3Vrt7U6HArLpzqOyIxuZrc1fS29Ei8HX5xaDKKOw=; b=KktDACmgpHp8LQAxPfKP1zjiKDizW3kn4MwB+K57BxPSjPIATdYeozkRXCNfJe7n6Y uYSf4Iz6FhQQVnQoI028VZVKEKQOYB3nDYq9IM3KNRXrQepwRWozsqGr0z833WSfKN0e pYrzxxpc2GlwO4QRxBNWMLLpmyR9erA+/XnU2NLGlJNnvQdhmVkldOO4nbd+87Xs1FjX T/pFZPG8YfpaPuvcfuz9Z2ulQkDQsyL/EdIKwLft8lAarCMfZEh4TNMcMX4dKlh74hj9 7QqPgdza6umCacDSQgzHuqbLluimqws2OFRR9oEFwvxFf4irYlWP77bhTt7sn4sL09sJ P/Qw== X-Gm-Message-State: AOAM531icA25QDV0NQe5LBJthIrWXnvPeOJBP8i4dNuIpjM6dS2TmOBG zQm9DknllrNqiwDVFoUlAWnqRgvgMO2Gfi0RI9TI66lz7Ep8JaIvZCD8TWwvTyVqUUTP8kxI8aF mZUcaIJLloFWFACb1 X-Received: by 2002:a1c:22d7:: with SMTP id i206mr2755086wmi.186.1591788970804; Wed, 10 Jun 2020 04:36:10 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxemEaCHMgCrHg7/oKSQ4yFnNXg1fLjZ5OHmMHvyeRIUoWRpQOB/0A8RO0HmZnjlr0fN5RKtA== X-Received: by 2002:a1c:22d7:: with SMTP id i206mr2755070wmi.186.1591788970615; Wed, 10 Jun 2020 04:36:10 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id a1sm6866225wmd.28.2020.06.10.04.36.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:10 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:08 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 05/14] vhost: reorder functions Message-ID: <20200610113515.1497099-6-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Reorder functions in the file to not rely on forward declarations, in preparation to making them static down the road. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 28f324fd77df..506208b63126 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2429,19 +2429,6 @@ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) } EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); -/* After we've used one of their buffers, we tell them about it. We'll then - * want to notify the guest, using eventfd. */ -int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) -{ - struct vring_used_elem heads = { - cpu_to_vhost32(vq, head), - cpu_to_vhost32(vq, len) - }; - - return vhost_add_used_n(vq, &heads, 1); -} -EXPORT_SYMBOL_GPL(vhost_add_used); - static int __vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, unsigned count) @@ -2511,6 +2498,19 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, } EXPORT_SYMBOL_GPL(vhost_add_used_n); +/* After we've used one of their buffers, we tell them about it. We'll then + * want to notify the guest, using eventfd. */ +int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) +{ + struct vring_used_elem heads = { + cpu_to_vhost32(vq, head), + cpu_to_vhost32(vq, len) + }; + + return vhost_add_used_n(vq, &heads, 1); +} +EXPORT_SYMBOL_GPL(vhost_add_used); + static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { __u16 old, new; From patchwork Wed Jun 10 11:36:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217865 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34643C433E0 for ; Wed, 10 Jun 2020 11:37:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08C9C204EC for ; Wed, 10 Jun 2020 11:37:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bVFmEACu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728899AbgFJLhq (ORCPT ); Wed, 10 Jun 2020 07:37:46 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:38212 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728629AbgFJLgS (ORCPT ); Wed, 10 Jun 2020 07:36:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788976; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=eiJhq6XkiotudOh+ZUxsjtY7w6RhDlW9rQ8WDNYh8GQ=; b=bVFmEACuVOQxdotsJMN90zuG3AsNEZ3qb7hhAYac7EB2GWc2447aE9YVxQ5kg6Y/ZF9OON dfrZn26upCXzu2/0O9TGvRyomeJ0+4mBW5SrFPtEtjyrZrN9uCHala0mx6F2k2Ir6Rsx3U nJ8S5jNsIaVhIDv+YAHfg8TYD0cxShc= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-166-mMJTc2CXPeeWvk37ZC6H1w-1; Wed, 10 Jun 2020 07:36:15 -0400 X-MC-Unique: mMJTc2CXPeeWvk37ZC6H1w-1 Received: by mail-wr1-f69.google.com with SMTP id p9so966407wrx.10 for ; Wed, 10 Jun 2020 04:36:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=eiJhq6XkiotudOh+ZUxsjtY7w6RhDlW9rQ8WDNYh8GQ=; b=YEVgf/ddLinah5+f4EeUYkAw462R5kvliz1fPB3zGCtJEn7X+sUkAQHaN/tvfTHltC HoCAiLrkdcz/5cy051vnlOLwO7rPhhyf2/aMlczw/mdw+xHkY3rKGMXIQMYg1toe660d g4eQYz57mT2wFi5Ir3Z2UkSrvXCePNyOrpz6jFYZlsuEcw79dcyfjx+9ACsAqGHGQ7lv 0Uvqt3zoYGh186mK1tu8ijlgPkvQAyy6SB2lTEzS4FNK7xaF7BfIUIWwLfCLv37EinIY txPozDnkS2lwP2vRun797oniBdpSgqDG9E5EqqrCxV0N4FxxhppCTejTJ9uWNVTGdiae 6J3A== X-Gm-Message-State: AOAM530Xc6s11UQ8qI3l4xlpgTcisjqtfYB/XxoN/UFnly8aE0jL6OwO nWzfABnSuJpGYCUoGMuL9kQph2W+yzZtJJ2qGVk9c7OWeZWIL2QPnzAozhSO9u6NdT4VPQlgj1x yygtctAV3Xeq5xh7I X-Received: by 2002:a05:6000:90:: with SMTP id m16mr3301317wrx.191.1591788973793; Wed, 10 Jun 2020 04:36:13 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw3FpICO0VZ3PPjidPQ1UtjzBsY39xeOmErAI9iBPh+xj1HDRPcA/UbjrzbUg24Tj112L9uRg== X-Received: by 2002:a05:6000:90:: with SMTP id m16mr3301287wrx.191.1591788973510; Wed, 10 Jun 2020 04:36:13 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id b132sm6626772wmh.3.2020.06.10.04.36.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:13 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:10 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 06/14] vhost: format-independent API for used buffers Message-ID: <20200610113515.1497099-7-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a new API that doesn't assume used ring, heads, etc. For now, we keep the old APIs around to make it easier to convert drivers. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 52 ++++++++++++++++++++++++++++++++++--------- drivers/vhost/vhost.h | 17 +++++++++++++- 2 files changed, 58 insertions(+), 11 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 506208b63126..e5763d81bf0f 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2339,13 +2339,12 @@ static void unfetch_descs(struct vhost_virtqueue *vq) * number of output then some number of input descriptors, it's actually two * iovecs, but we pack them into one and note how many of each there were. * - * This function returns the descriptor number found, or vq->num (which is - * never a valid descriptor number) if none was found. A negative code is - * returned on error. */ -int vhost_get_vq_desc(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num) + * This function returns a value > 0 if a descriptor was found, or 0 if none were found. + * A negative code is returned on error. */ +int vhost_get_avail_buf(struct vhost_virtqueue *vq, struct vhost_buf *buf, + struct iovec iov[], unsigned int iov_size, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num) { int ret = fetch_descs(vq); int i; @@ -2358,6 +2357,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, *out_num = *in_num = 0; if (unlikely(log)) *log_num = 0; + buf->in_len = buf->out_len = 0; + buf->descs = 0; for (i = vq->first_desc; i < vq->ndescs; ++i) { unsigned iov_count = *in_num + *out_num; @@ -2387,6 +2388,7 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* If this is an input descriptor, * increment that count. */ *in_num += ret; + buf->in_len += desc->len; if (unlikely(log && ret)) { log[*log_num].addr = desc->addr; log[*log_num].len = desc->len; @@ -2402,9 +2404,11 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, goto err; } *out_num += ret; + buf->out_len += desc->len; } - ret = desc->id; + buf->id = desc->id; + ++buf->descs; if (!(desc->flags & VRING_DESC_F_NEXT)) break; @@ -2412,14 +2416,22 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, vq->first_desc = i + 1; - return ret; + return 1; err: unfetch_descs(vq); return ret ? ret : vq->num; } -EXPORT_SYMBOL_GPL(vhost_get_vq_desc); +EXPORT_SYMBOL_GPL(vhost_get_avail_buf); + +/* Reverse the effect of vhost_get_avail_buf. Useful for error handling. */ +void vhost_discard_avail_bufs(struct vhost_virtqueue *vq, + struct vhost_buf *buf, unsigned count) +{ + vhost_discard_vq_desc(vq, count); +} +EXPORT_SYMBOL_GPL(vhost_discard_avail_bufs); /* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) @@ -2511,6 +2523,26 @@ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) } EXPORT_SYMBOL_GPL(vhost_add_used); +int vhost_put_used_buf(struct vhost_virtqueue *vq, struct vhost_buf *buf) +{ + return vhost_add_used(vq, buf->id, buf->in_len); +} +EXPORT_SYMBOL_GPL(vhost_put_used_buf); + +int vhost_put_used_n_bufs(struct vhost_virtqueue *vq, + struct vhost_buf *bufs, unsigned count) +{ + unsigned i; + + for (i = 0; i < count; ++i) { + vq->heads[i].id = cpu_to_vhost32(vq, bufs[i].id); + vq->heads[i].len = cpu_to_vhost32(vq, bufs[i].in_len); + } + + return vhost_add_used_n(vq, vq->heads, count); +} +EXPORT_SYMBOL_GPL(vhost_put_used_n_bufs); + static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) { __u16 old, new; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index fed36af5c444..28eea0155efb 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -67,6 +67,13 @@ struct vhost_desc { u16 id; }; +struct vhost_buf { + u32 out_len; + u32 in_len; + u16 descs; + u16 id; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -195,7 +202,12 @@ int vhost_get_vq_desc(struct vhost_virtqueue *, unsigned int *out_num, unsigned int *in_num, struct vhost_log *log, unsigned int *log_num); void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); - +int vhost_get_avail_buf(struct vhost_virtqueue *, struct vhost_buf *buf, + struct iovec iov[], unsigned int iov_count, + unsigned int *out_num, unsigned int *in_num, + struct vhost_log *log, unsigned int *log_num); +void vhost_discard_avail_bufs(struct vhost_virtqueue *, + struct vhost_buf *, unsigned count); int vhost_vq_init_access(struct vhost_virtqueue *); int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len); int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads, @@ -204,6 +216,9 @@ void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, unsigned int id, int len); void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, struct vring_used_elem *heads, unsigned count); +int vhost_put_used_buf(struct vhost_virtqueue *, struct vhost_buf *buf); +int vhost_put_used_n_bufs(struct vhost_virtqueue *, + struct vhost_buf *bufs, unsigned count); void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *); void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *); bool vhost_vq_avail_empty(struct vhost_dev *, struct vhost_virtqueue *); From patchwork Wed Jun 10 11:36:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217866 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34F86C433E1 for ; Wed, 10 Jun 2020 11:37:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F25C6204EC for ; Wed, 10 Jun 2020 11:37:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YB13BNXY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728828AbgFJLhQ (ORCPT ); Wed, 10 Jun 2020 07:37:16 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:23748 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728481AbgFJLga (ORCPT ); Wed, 10 Jun 2020 07:36:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788987; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UNoiNEJvdgOZ9xjiajXEUBmq7bdVAGmYmXBWji52Kn0=; b=YB13BNXYWkhc0kqqX+ta5hIQYnDlzhtQjpLKfZpE2ADSHuVqhZWr2joJV0niLRct+GhRKa 10mZIvhsa8mEdiPYzr3co0vJkggE3x6Z/W7btBGfIrQRNmk4DnHlt8vv7h3Duc1QJkNpj7 IpqS7HoR2CzNPInh/SZ04u/Ya+qe96g= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-167-B8ns1hqjMuGMCMtuex8w_w-1; Wed, 10 Jun 2020 07:36:23 -0400 X-MC-Unique: B8ns1hqjMuGMCMtuex8w_w-1 Received: by mail-wr1-f69.google.com with SMTP id w16so954053wru.18 for ; Wed, 10 Jun 2020 04:36:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=UNoiNEJvdgOZ9xjiajXEUBmq7bdVAGmYmXBWji52Kn0=; b=JVPFll/LFWk2fNf9DeD51tYlZO3Srk55YU2x8drvIAsxV/rg5Qo/nK/Wc4i5A1wo83 UkjLIMSR+PPIgZraMW3NkukqiCFtwFGPhpdqK9UNKQyAv24H9qRBqRIGUx8cNjXx/ZRy I3zsMimVYA5CpIbkZezf5BOrfMQxlAFQnoHhyO6JOMHULuuCuAKFR5jRJ52ACRaoEtlX 7ZHDsqfTwDislBgge8VpAxzXl6S3CK1uQmE6xjQXDEgD+c7IfhmTRv44dkV62q/mf+CF 4i8FMK6nG4ZS9iGlcjAInkHXfd1jWkjvyFy2njIq2F2gxxcV6EAQDYqT+HyWdgcP1++n RpXQ== X-Gm-Message-State: AOAM532C7c/MI2g1WZAu4U3z7gz0q4li7/VPrq2v8hi71mRpxednxNWz QsKqWrRzmLPzDkuXF2J5htZzTAyDd8CG7HV1sBG2dRtn8jvLqDjaARYDD32DeOS8kqO27+RLvev l/nND/a7ICSfOziJb X-Received: by 2002:a5d:440c:: with SMTP id z12mr3268428wrq.241.1591788982305; Wed, 10 Jun 2020 04:36:22 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwXGUgH38dPw7JvUUtamSsjhEq0TgT1zn0wn1ZH4IjU6BlsD9AgrHYHsB3Wss1dcFdfVl3Zig== X-Received: by 2002:a5d:440c:: with SMTP id z12mr3268375wrq.241.1591788981792; Wed, 10 Jun 2020 04:36:21 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id e5sm7970763wrw.19.2020.06.10.04.36.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:21 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:19 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 09/14] vhost/net: convert to new API: heads->bufs Message-ID: <20200610113515.1497099-10-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Convert vhost net to use the new format-agnostic API. In particular, don't poke at vq internals such as the heads array. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/net.c | 154 +++++++++++++++++++++++--------------------- 1 file changed, 82 insertions(+), 72 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index ff594eec8ae3..830fe84912a5 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -59,13 +59,13 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" * status internally; used for zerocopy tx only. */ /* Lower device DMA failed */ -#define VHOST_DMA_FAILED_LEN ((__force __virtio32)3) +#define VHOST_DMA_FAILED_LEN (3) /* Lower device DMA done */ -#define VHOST_DMA_DONE_LEN ((__force __virtio32)2) +#define VHOST_DMA_DONE_LEN (2) /* Lower device DMA in progress */ -#define VHOST_DMA_IN_PROGRESS ((__force __virtio32)1) +#define VHOST_DMA_IN_PROGRESS (1) /* Buffer unused */ -#define VHOST_DMA_CLEAR_LEN ((__force __virtio32)0) +#define VHOST_DMA_CLEAR_LEN (0) #define VHOST_DMA_IS_DONE(len) ((__force u32)(len) >= (__force u32)VHOST_DMA_DONE_LEN) @@ -112,9 +112,12 @@ struct vhost_net_virtqueue { /* last used idx for outstanding DMA zerocopy buffers */ int upend_idx; /* For TX, first used idx for DMA done zerocopy buffers - * For RX, number of batched heads + * For RX, number of batched bufs */ int done_idx; + /* Outstanding user bufs. UIO_MAXIOV in length. */ + /* TODO: we can make this smaller for sure. */ + struct vhost_buf *bufs; /* Number of XDP frames batched */ int batched_xdp; /* an array of userspace buffers info */ @@ -271,6 +274,8 @@ static void vhost_net_clear_ubuf_info(struct vhost_net *n) int i; for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + kfree(n->vqs[i].bufs); + n->vqs[i].bufs = NULL; kfree(n->vqs[i].ubuf_info); n->vqs[i].ubuf_info = NULL; } @@ -282,6 +287,12 @@ static int vhost_net_set_ubuf_info(struct vhost_net *n) int i; for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { + n->vqs[i].bufs = kmalloc_array(UIO_MAXIOV, + sizeof(*n->vqs[i].bufs), + GFP_KERNEL); + if (!n->vqs[i].bufs) + goto err; + zcopy = vhost_net_zcopy_mask & (0x1 << i); if (!zcopy) continue; @@ -364,18 +375,18 @@ static void vhost_zerocopy_signal_used(struct vhost_net *net, int j = 0; for (i = nvq->done_idx; i != nvq->upend_idx; i = (i + 1) % UIO_MAXIOV) { - if (vq->heads[i].len == VHOST_DMA_FAILED_LEN) + if (nvq->bufs[i].in_len == VHOST_DMA_FAILED_LEN) vhost_net_tx_err(net); - if (VHOST_DMA_IS_DONE(vq->heads[i].len)) { - vq->heads[i].len = VHOST_DMA_CLEAR_LEN; + if (VHOST_DMA_IS_DONE(nvq->bufs[i].in_len)) { + nvq->bufs[i].in_len = VHOST_DMA_CLEAR_LEN; ++j; } else break; } while (j) { add = min(UIO_MAXIOV - nvq->done_idx, j); - vhost_add_used_and_signal_n(vq->dev, vq, - &vq->heads[nvq->done_idx], add); + vhost_put_used_n_bufs(vq, &nvq->bufs[nvq->done_idx], add); + vhost_signal(vq->dev, vq); nvq->done_idx = (nvq->done_idx + add) % UIO_MAXIOV; j -= add; } @@ -390,7 +401,7 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success) rcu_read_lock_bh(); /* set len to mark this desc buffers done DMA */ - nvq->vq.heads[ubuf->desc].in_len = success ? + nvq->bufs[ubuf->desc].in_len = success ? VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN; cnt = vhost_net_ubuf_put(ubufs); @@ -452,7 +463,8 @@ static void vhost_net_signal_used(struct vhost_net_virtqueue *nvq) if (!nvq->done_idx) return; - vhost_add_used_and_signal_n(dev, vq, vq->heads, nvq->done_idx); + vhost_put_used_n_bufs(vq, nvq->bufs, nvq->done_idx); + vhost_signal(dev, vq); nvq->done_idx = 0; } @@ -558,6 +570,7 @@ static void vhost_net_busy_poll(struct vhost_net *net, static int vhost_net_tx_get_vq_desc(struct vhost_net *net, struct vhost_net_virtqueue *tnvq, + struct vhost_buf *buf, unsigned int *out_num, unsigned int *in_num, struct msghdr *msghdr, bool *busyloop_intr) { @@ -565,10 +578,10 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, struct vhost_virtqueue *rvq = &rnvq->vq; struct vhost_virtqueue *tvq = &tnvq->vq; - int r = vhost_get_vq_desc(tvq, tvq->iov, ARRAY_SIZE(tvq->iov), - out_num, in_num, NULL, NULL); + int r = vhost_get_avail_buf(tvq, buf, tvq->iov, ARRAY_SIZE(tvq->iov), + out_num, in_num, NULL, NULL); - if (r == tvq->num && tvq->busyloop_timeout) { + if (!r && tvq->busyloop_timeout) { /* Flush batched packets first */ if (!vhost_sock_zcopy(vhost_vq_get_backend(tvq))) vhost_tx_batch(net, tnvq, @@ -577,8 +590,8 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, false); - r = vhost_get_vq_desc(tvq, tvq->iov, ARRAY_SIZE(tvq->iov), - out_num, in_num, NULL, NULL); + r = vhost_get_avail_buf(tvq, buf, tvq->iov, ARRAY_SIZE(tvq->iov), + out_num, in_num, NULL, NULL); } return r; @@ -607,6 +620,7 @@ static size_t init_iov_iter(struct vhost_virtqueue *vq, struct iov_iter *iter, static int get_tx_bufs(struct vhost_net *net, struct vhost_net_virtqueue *nvq, + struct vhost_buf *buf, struct msghdr *msg, unsigned int *out, unsigned int *in, size_t *len, bool *busyloop_intr) @@ -614,9 +628,9 @@ static int get_tx_bufs(struct vhost_net *net, struct vhost_virtqueue *vq = &nvq->vq; int ret; - ret = vhost_net_tx_get_vq_desc(net, nvq, out, in, msg, busyloop_intr); + ret = vhost_net_tx_get_vq_desc(net, nvq, buf, out, in, msg, busyloop_intr); - if (ret < 0 || ret == vq->num) + if (ret <= 0) return ret; if (*in) { @@ -761,7 +775,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; struct vhost_virtqueue *vq = &nvq->vq; unsigned out, in; - int head; + int ret; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, @@ -773,6 +787,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) int err; int sent_pkts = 0; bool sock_can_batch = (sock->sk->sk_sndbuf == INT_MAX); + struct vhost_buf buf; do { bool busyloop_intr = false; @@ -780,13 +795,13 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) if (nvq->done_idx == VHOST_NET_BATCH) vhost_tx_batch(net, nvq, sock, &msg); - head = get_tx_bufs(net, nvq, &msg, &out, &in, &len, - &busyloop_intr); + ret = get_tx_bufs(net, nvq, &buf, &msg, &out, &in, &len, + &busyloop_intr); /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) + if (unlikely(ret < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { + if (!ret) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, @@ -808,7 +823,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) goto done; } else if (unlikely(err != -ENOSPC)) { vhost_tx_batch(net, nvq, sock, &msg); - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } @@ -829,7 +844,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(sock, &msg, len); if (unlikely(err < 0)) { - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } @@ -837,8 +852,7 @@ static void handle_tx_copy(struct vhost_net *net, struct socket *sock) pr_debug("Truncated TX packet: len %d != %zd\n", err, len); done: - vq->heads[nvq->done_idx].id = cpu_to_vhost32(vq, head); - vq->heads[nvq->done_idx].len = 0; + nvq->bufs[nvq->done_idx] = buf; ++nvq->done_idx; } while (likely(!vhost_exceeds_weight(vq, ++sent_pkts, total_len))); @@ -850,7 +864,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct vhost_net_virtqueue *nvq = &net->vqs[VHOST_NET_VQ_TX]; struct vhost_virtqueue *vq = &nvq->vq; unsigned out, in; - int head; + int ret; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, @@ -864,6 +878,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct vhost_net_ubuf_ref *uninitialized_var(ubufs); bool zcopy_used; int sent_pkts = 0; + struct vhost_buf buf; do { bool busyloop_intr; @@ -872,13 +887,13 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) vhost_zerocopy_signal_used(net, vq); busyloop_intr = false; - head = get_tx_bufs(net, nvq, &msg, &out, &in, &len, - &busyloop_intr); + ret = get_tx_bufs(net, nvq, &buf, &msg, &out, &in, &len, + &busyloop_intr); /* On error, stop handling until the next kick. */ - if (unlikely(head < 0)) + if (unlikely(ret < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ - if (head == vq->num) { + if (!ret) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, vq))) { @@ -897,8 +912,8 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) struct ubuf_info *ubuf; ubuf = nvq->ubuf_info + nvq->upend_idx; - vq->heads[nvq->upend_idx].id = cpu_to_vhost32(vq, head); - vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; + nvq->bufs[nvq->upend_idx] = buf; + nvq->bufs[nvq->upend_idx].in_len = VHOST_DMA_IN_PROGRESS; ubuf->callback = vhost_zerocopy_callback; ubuf->ctx = nvq->ubufs; ubuf->desc = nvq->upend_idx; @@ -930,17 +945,19 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) nvq->upend_idx = ((unsigned)nvq->upend_idx - 1) % UIO_MAXIOV; } - vhost_discard_vq_desc(vq, 1); + vhost_discard_avail_bufs(vq, &buf, 1); vhost_net_enable_vq(net, vq); break; } if (err != len) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); - if (!zcopy_used) - vhost_add_used_and_signal(&net->dev, vq, head, 0); - else + if (!zcopy_used) { + vhost_put_used_buf(vq, &buf); + vhost_signal(&net->dev, vq); + } else { vhost_zerocopy_signal_used(net, vq); + } vhost_net_tx_packet(net); } while (likely(!vhost_exceeds_weight(vq, ++sent_pkts, total_len))); } @@ -1004,7 +1021,7 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk, int len = peek_head_len(rnvq, sk); if (!len && rvq->busyloop_timeout) { - /* Flush batched heads first */ + /* Flush batched bufs first */ vhost_net_signal_used(rnvq); /* Both tx vq and rx socket were polled here */ vhost_net_busy_poll(net, rvq, tvq, busyloop_intr, true); @@ -1022,11 +1039,11 @@ static int vhost_net_rx_peek_head_len(struct vhost_net *net, struct sock *sk, * @iovcount - returned count of io vectors we fill * @log - vhost log * @log_num - log offset - * @quota - headcount quota, 1 for big buffer - * returns number of buffer heads allocated, negative on error + * @quota - bufcount quota, 1 for big buffer + * returns number of buffers allocated, negative on error */ static int get_rx_bufs(struct vhost_virtqueue *vq, - struct vring_used_elem *heads, + struct vhost_buf *bufs, int datalen, unsigned *iovcount, struct vhost_log *log, @@ -1035,30 +1052,24 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, { unsigned int out, in; int seg = 0; - int headcount = 0; - unsigned d; + int bufcount = 0; int r, nlogs = 0; /* len is always initialized before use since we are always called with * datalen > 0. */ u32 uninitialized_var(len); - while (datalen > 0 && headcount < quota) { + while (datalen > 0 && bufcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { r = -ENOBUFS; goto err; } - r = vhost_get_vq_desc(vq, vq->iov + seg, - ARRAY_SIZE(vq->iov) - seg, &out, - &in, log, log_num); - if (unlikely(r < 0)) + r = vhost_get_avail_buf(vq, bufs + bufcount, vq->iov + seg, + ARRAY_SIZE(vq->iov) - seg, &out, + &in, log, log_num); + if (unlikely(r <= 0)) goto err; - d = r; - if (d == vq->num) { - r = 0; - goto err; - } if (unlikely(out || in <= 0)) { vq_err(vq, "unexpected descriptor format for RX: " "out %d, in %d\n", out, in); @@ -1069,14 +1080,12 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, nlogs += *log_num; log += *log_num; } - heads[headcount].id = cpu_to_vhost32(vq, d); len = iov_length(vq->iov + seg, in); - heads[headcount].len = cpu_to_vhost32(vq, len); datalen -= len; - ++headcount; + ++bufcount; seg += in; } - heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen); + bufs[bufcount - 1].in_len = len + datalen; *iovcount = seg; if (unlikely(log)) *log_num = nlogs; @@ -1086,9 +1095,9 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, r = UIO_MAXIOV + 1; goto err; } - return headcount; + return bufcount; err: - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, bufs, bufcount); return r; } @@ -1113,7 +1122,7 @@ static void handle_rx(struct vhost_net *net) }; size_t total_len = 0; int err, mergeable; - s16 headcount; + int bufcount; size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; bool busyloop_intr = false; @@ -1147,14 +1156,14 @@ static void handle_rx(struct vhost_net *net) break; sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; - headcount = get_rx_bufs(vq, vq->heads + nvq->done_idx, - vhost_len, &in, vq_log, &log, - likely(mergeable) ? UIO_MAXIOV : 1); + bufcount = get_rx_bufs(vq, nvq->bufs + nvq->done_idx, + vhost_len, &in, vq_log, &log, + likely(mergeable) ? UIO_MAXIOV : 1); /* On error, stop handling until the next kick. */ - if (unlikely(headcount < 0)) + if (unlikely(bufcount < 0)) goto out; /* OK, now we need to know about added descriptors. */ - if (!headcount) { + if (!bufcount) { if (unlikely(busyloop_intr)) { vhost_poll_queue(&vq->poll); } else if (unlikely(vhost_enable_notify(&net->dev, vq))) { @@ -1171,7 +1180,7 @@ static void handle_rx(struct vhost_net *net) if (nvq->rx_ring) msg.msg_control = vhost_net_buf_consume(&nvq->rxq); /* On overrun, truncate and discard */ - if (unlikely(headcount > UIO_MAXIOV)) { + if (unlikely(bufcount > UIO_MAXIOV)) { iov_iter_init(&msg.msg_iter, READ, vq->iov, 1, 1); err = sock->ops->recvmsg(sock, &msg, 1, MSG_DONTWAIT | MSG_TRUNC); @@ -1195,7 +1204,7 @@ static void handle_rx(struct vhost_net *net) if (unlikely(err != sock_len)) { pr_debug("Discarded rx packet: " " len %d, expected %zd\n", err, sock_len); - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, nvq->bufs + nvq->done_idx, bufcount); continue; } /* Supply virtio_net_hdr if VHOST_NET_F_VIRTIO_NET_HDR */ @@ -1214,15 +1223,15 @@ static void handle_rx(struct vhost_net *net) } /* TODO: Should check and handle checksum. */ - num_buffers = cpu_to_vhost16(vq, headcount); + num_buffers = cpu_to_vhost16(vq, bufcount); if (likely(mergeable) && copy_to_iter(&num_buffers, sizeof num_buffers, &fixup) != sizeof num_buffers) { vq_err(vq, "Failed num_buffers write"); - vhost_discard_vq_desc(vq, headcount); + vhost_discard_avail_bufs(vq, nvq->bufs + nvq->done_idx, bufcount); goto out; } - nvq->done_idx += headcount; + nvq->done_idx += bufcount; if (nvq->done_idx > VHOST_NET_BATCH) vhost_net_signal_used(nvq); if (unlikely(vq_log)) @@ -1314,6 +1323,7 @@ static int vhost_net_open(struct inode *inode, struct file *f) n->vqs[VHOST_NET_VQ_TX].vq.handle_kick = handle_tx_kick; n->vqs[VHOST_NET_VQ_RX].vq.handle_kick = handle_rx_kick; for (i = 0; i < VHOST_NET_VQ_MAX; i++) { + n->vqs[i].bufs = NULL; n->vqs[i].ubufs = NULL; n->vqs[i].ubuf_info = NULL; n->vqs[i].upend_idx = 0; From patchwork Wed Jun 10 11:36:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217868 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EA60FC433E0 for ; Wed, 10 Jun 2020 11:36:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF50B204EC for ; Wed, 10 Jun 2020 11:36:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OEzjN2Fx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728717AbgFJLge (ORCPT ); Wed, 10 Jun 2020 07:36:34 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:38673 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728694AbgFJLg2 (ORCPT ); Wed, 10 Jun 2020 07:36:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788987; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8yeTF/4xoJH8JkJEZ+aqTMVrfSsZomUNfl5tfcaaPRM=; b=OEzjN2FxH15PLi8yuz9UCOtxvN4Eu5l/ARH2uho30fxJbiO88TF4FGObcAmvLvkGsJV4VT ZDLpNp3igpDgY1BuXvMVjVYk6SPpauigr1TSFfeJAkNV+QUnBYQSfjjF/pI90fAzyhP8SB LAphuv+k0oaCbpfkRHtrdtRcRkzPDpc= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-249-5YaSr65COjKcaUtT9NFc8g-1; Wed, 10 Jun 2020 07:36:25 -0400 X-MC-Unique: 5YaSr65COjKcaUtT9NFc8g-1 Received: by mail-wr1-f71.google.com with SMTP id j16so946579wre.22 for ; Wed, 10 Jun 2020 04:36:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=8yeTF/4xoJH8JkJEZ+aqTMVrfSsZomUNfl5tfcaaPRM=; b=uUvvbq4eAcVkRlX7VVIci7n2+QhYFwU3E+Y4YIkMyHMraygTpcva6zX+pLiWuK78GR xe3jqOQI+CNhFLC8CB+Dif0AZBNsMDmh78uu17WSSX9GZ/YFaSVVmT+XWyY0vBbkTlgK JyEw229THvk5nqikXXHcdhCqeI8LD4UaMATpoi5NpoEnD+V2lKSr0OKuJEr3NoOavKyZ eNJT5MqfEeJfXI92n/XAc1prEoL9QR6rkPE7gPits7uBVLNSfFCCsYzeQ6HeGoyVj8qs W/+UCRwAZ5Z8CyEEkwpOkt6T85PmDw/6U7socboqxHSco3sIx1991ZmXZVg44qtjTQa1 L9Gw== X-Gm-Message-State: AOAM530GCSGMXIDdf2HzzUNHrm2c1D6OGkN5jr47NrKhTQu/+6Muxywv 2Xv+MZOweU/V/bpfAowmvpHmkYHHjFLXAx9F06g+asJQqALuRddq5VvevQ2TXqoPyoNzAQKAnLR e+rpEJz5+mO8VRkUq X-Received: by 2002:adf:f611:: with SMTP id t17mr3115449wrp.69.1591788984597; Wed, 10 Jun 2020 04:36:24 -0700 (PDT) X-Google-Smtp-Source: ABdhPJySUb6SmdRetYLS6/lDFnA63vhXBdDD3cCFK65tVJXhEwb5+hLdb3cRehsL9GzZU3pDEV7NVg== X-Received: by 2002:adf:f611:: with SMTP id t17mr3115431wrp.69.1591788984381; Wed, 10 Jun 2020 04:36:24 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id x8sm7694296wrs.43.2020.06.10.04.36.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:23 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:22 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 10/14] vhost/net: avoid iov length math Message-ID: <20200610113515.1497099-11-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Now that API exposes buffer length, we no longer need to scan IOVs to figure it out. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/net.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 830fe84912a5..0b509be8d7b1 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -607,11 +607,9 @@ static bool vhost_exceeds_maxpend(struct vhost_net *net) } static size_t init_iov_iter(struct vhost_virtqueue *vq, struct iov_iter *iter, - size_t hdr_size, int out) + size_t len, size_t hdr_size, int out) { /* Skip header. TODO: support TSO. */ - size_t len = iov_length(vq->iov, out); - iov_iter_init(iter, WRITE, vq->iov, out, len); iov_iter_advance(iter, hdr_size); @@ -640,7 +638,7 @@ static int get_tx_bufs(struct vhost_net *net, } /* Sanity check */ - *len = init_iov_iter(vq, &msg->msg_iter, nvq->vhost_hlen, *out); + *len = init_iov_iter(vq, &msg->msg_iter, buf->out_len, nvq->vhost_hlen, *out); if (*len == 0) { vq_err(vq, "Unexpected header len for TX: %zd expected %zd\n", *len, nvq->vhost_hlen); @@ -1080,7 +1078,7 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, nlogs += *log_num; log += *log_num; } - len = iov_length(vq->iov + seg, in); + len = bufs[bufcount].in_len; datalen -= len; ++bufcount; seg += in; From patchwork Wed Jun 10 11:36:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 217867 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DEA12C433DF for ; Wed, 10 Jun 2020 11:36:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFC612074B for ; Wed, 10 Jun 2020 11:36:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OAkSCFdI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728786AbgFJLg5 (ORCPT ); Wed, 10 Jun 2020 07:36:57 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:22920 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728746AbgFJLgk (ORCPT ); Wed, 10 Jun 2020 07:36:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591788998; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=cEu9UKQDih3Vjd1MZ21gGzO+ccbzDvhEg895z/Nzqys=; b=OAkSCFdIpGS6mr4FLSvtVLeBsR9e2BThVNPgBmK8jJV697YxpSdOGUIjIn1G/zQhR2rvjS Ig/NQ7i40BL9RHRJ6zcDvOu1LskMAcD39DCiMj7QckZ6Bg1DGrRv5cAsnIaZrW349J6Rcr 8MsHkUtc4nY5oFyAyTP16Fkn0ykoC74= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-186-jelw4d2qPJ27cJg2yrfWCw-1; Wed, 10 Jun 2020 07:36:37 -0400 X-MC-Unique: jelw4d2qPJ27cJg2yrfWCw-1 Received: by mail-wr1-f69.google.com with SMTP id w4so965393wrl.13 for ; Wed, 10 Jun 2020 04:36:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=cEu9UKQDih3Vjd1MZ21gGzO+ccbzDvhEg895z/Nzqys=; b=h8gSNvcG7+WjUGWjceKjaXwMf882jEQHVXP/GHy5XJx5ZjYtjVJI3jm7YJMXRFCAmt NoWxwzCtvud1esLkjGnYn0W3LxIKhDL0JEuwVtbWLGpwjSwmsK6V/MQ60E5LzO32DqBC 2uGpdKnFaFwBc6MGqGqUzvu0dbItJBcGYYEts3Q2OxGlqXxTSjYl7L5Sbsl9LJbRuQTl NIjxaTz9+KD5JzyNK8VFIX0NSDk+Qu1Jb78aE0h+wZa/DyXkJWoSJ+XT096245+mWdUk eutGAq1BV1Tj2PY6jZtRg2TmU2LICXpKo2fhdoVuQxKX18P4GssDBX2Z1lZir9n39B/l HZgQ== X-Gm-Message-State: AOAM531JG07WffQEzcHnsduZUidgLCerICxIJK0G7wM33kGFD7aq8q5y L4v5xWuUki8c4oJYuX06K0DMXOVji4IyjVnSsnq3yV/RrlFOo7mJ569I+cw6Smln3sjob+r6YJJ TOREKBdz/1pZuFNaW X-Received: by 2002:adf:dcd2:: with SMTP id x18mr3204089wrm.258.1591788995970; Wed, 10 Jun 2020 04:36:35 -0700 (PDT) X-Google-Smtp-Source: ABdhPJz+lrg/RmUfW2lVPzuXlXWaz8rOcMJq8w1XKgyPuKyHyoR97XZsCDeD1ieVxspClyZH+J9RRQ== X-Received: by 2002:adf:dcd2:: with SMTP id x18mr3204063wrm.258.1591788995672; Wed, 10 Jun 2020 04:36:35 -0700 (PDT) Received: from redhat.com ([212.92.121.57]) by smtp.gmail.com with ESMTPSA id d9sm7727647wre.28.2020.06.10.04.36.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 Jun 2020 04:36:35 -0700 (PDT) Date: Wed, 10 Jun 2020 07:36:33 -0400 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, Jason Wang , eperezma@redhat.com Subject: [PATCH RFC v7 14/14] vhost: drop head based APIs Message-ID: <20200610113515.1497099-15-mst@redhat.com> References: <20200610113515.1497099-1-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200610113515.1497099-1-mst@redhat.com> X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Everyone's using buf APIs, no need for head based ones anymore. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 64 ++++++------------------------------------- drivers/vhost/vhost.h | 12 -------- 2 files changed, 8 insertions(+), 68 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 03e6bca02288..9096bd291c91 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -2425,39 +2425,11 @@ EXPORT_SYMBOL_GPL(vhost_get_avail_buf); void vhost_discard_avail_bufs(struct vhost_virtqueue *vq, struct vhost_buf *buf, unsigned count) { - vhost_discard_vq_desc(vq, count); + unfetch_descs(vq); + vq->last_avail_idx -= count; } EXPORT_SYMBOL_GPL(vhost_discard_avail_bufs); -/* This function returns the descriptor number found, or vq->num (which is - * never a valid descriptor number) if none was found. A negative code is - * returned on error. */ -int vhost_get_vq_desc(struct vhost_virtqueue *vq, - struct iovec iov[], unsigned int iov_size, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num) -{ - struct vhost_buf buf; - int ret = vhost_get_avail_buf(vq, &buf, - iov, iov_size, out_num, in_num, - log, log_num); - - if (likely(ret > 0)) - return buf->id; - if (likely(!ret)) - return vq->num; - return ret; -} -EXPORT_SYMBOL_GPL(vhost_get_vq_desc); - -/* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */ -void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n) -{ - unfetch_descs(vq); - vq->last_avail_idx -= n; -} -EXPORT_SYMBOL_GPL(vhost_discard_vq_desc); - static int __vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, unsigned count) @@ -2490,8 +2462,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, return 0; } -/* After we've used one of their buffers, we tell them about it. We'll then - * want to notify the guest, using eventfd. */ +static int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, unsigned count) { @@ -2525,10 +2496,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, } return r; } -EXPORT_SYMBOL_GPL(vhost_add_used_n); -/* After we've used one of their buffers, we tell them about it. We'll then - * want to notify the guest, using eventfd. */ +static int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) { struct vring_used_elem heads = { @@ -2538,14 +2507,17 @@ int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len) return vhost_add_used_n(vq, &heads, 1); } -EXPORT_SYMBOL_GPL(vhost_add_used); +/* After we've used one of their buffers, we tell them about it. We'll then + * want to notify the guest, using vhost_signal. */ int vhost_put_used_buf(struct vhost_virtqueue *vq, struct vhost_buf *buf) { return vhost_add_used(vq, buf->id, buf->in_len); } EXPORT_SYMBOL_GPL(vhost_put_used_buf); +/* After we've used one of their buffers, we tell them about it. We'll then + * want to notify the guest, using vhost_signal. */ int vhost_put_used_n_bufs(struct vhost_virtqueue *vq, struct vhost_buf *bufs, unsigned count) { @@ -2606,26 +2578,6 @@ void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) } EXPORT_SYMBOL_GPL(vhost_signal); -/* And here's the combo meal deal. Supersize me! */ -void vhost_add_used_and_signal(struct vhost_dev *dev, - struct vhost_virtqueue *vq, - unsigned int head, int len) -{ - vhost_add_used(vq, head, len); - vhost_signal(dev, vq); -} -EXPORT_SYMBOL_GPL(vhost_add_used_and_signal); - -/* multi-buffer version of vhost_add_used_and_signal */ -void vhost_add_used_and_signal_n(struct vhost_dev *dev, - struct vhost_virtqueue *vq, - struct vring_used_elem *heads, unsigned count) -{ - vhost_add_used_n(vq, heads, count); - vhost_signal(dev, vq); -} -EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n); - /* return true if we're sure that avaiable ring is empty */ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) { diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 28eea0155efb..264a2a2fae97 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -197,11 +197,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg bool vhost_vq_access_ok(struct vhost_virtqueue *vq); bool vhost_log_access_ok(struct vhost_dev *); -int vhost_get_vq_desc(struct vhost_virtqueue *, - struct iovec iov[], unsigned int iov_count, - unsigned int *out_num, unsigned int *in_num, - struct vhost_log *log, unsigned int *log_num); -void vhost_discard_vq_desc(struct vhost_virtqueue *, int n); int vhost_get_avail_buf(struct vhost_virtqueue *, struct vhost_buf *buf, struct iovec iov[], unsigned int iov_count, unsigned int *out_num, unsigned int *in_num, @@ -209,13 +204,6 @@ int vhost_get_avail_buf(struct vhost_virtqueue *, struct vhost_buf *buf, void vhost_discard_avail_bufs(struct vhost_virtqueue *, struct vhost_buf *, unsigned count); int vhost_vq_init_access(struct vhost_virtqueue *); -int vhost_add_used(struct vhost_virtqueue *, unsigned int head, int len); -int vhost_add_used_n(struct vhost_virtqueue *, struct vring_used_elem *heads, - unsigned count); -void vhost_add_used_and_signal(struct vhost_dev *, struct vhost_virtqueue *, - unsigned int id, int len); -void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *, - struct vring_used_elem *heads, unsigned count); int vhost_put_used_buf(struct vhost_virtqueue *, struct vhost_buf *buf); int vhost_put_used_n_bufs(struct vhost_virtqueue *, struct vhost_buf *bufs, unsigned count);