From: Yuanhan Liu Date: Thu, 10 Mar 2016 04:19:59 +0000 (+0800) Subject: vhost: get rid of linked list for devices X-Git-Tag: spdx-start~7474 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=45ca9c6f7bc65313f338b5baee84f2af5f28536d;p=dpdk.git vhost: get rid of linked list for devices While we use a single linked list to maintain all devices, we could use a static array to achieve the same goal, just like what we did to maintain the eth devices with rte_eth_devices array. This could simplifies the code a bit. Signed-off-by: Yuanhan Liu Acked-by: Huawei Xie --- diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c index fe1a77e80b..be91e5fb25 100644 --- a/lib/librte_vhost/virtio-net.c +++ b/lib/librte_vhost/virtio-net.c @@ -55,18 +55,11 @@ #include "vhost-net.h" #include "virtio-net.h" -/* - * Device linked list structure for configuration. - */ -struct virtio_net_config_ll { - struct virtio_net dev; /* Virtio device.*/ - struct virtio_net_config_ll *next; /* Next dev on linked list.*/ -}; +#define MAX_VHOST_DEVICE 1024 +static struct virtio_net *vhost_devices[MAX_VHOST_DEVICE]; /* device ops to add/remove device to/from data core. */ struct virtio_net_device_ops const *notify_ops; -/* root address of the linked list of managed virtio devices */ -static struct virtio_net_config_ll *ll_root; #define VHOST_USER_F_PROTOCOL_FEATURES 30 @@ -116,77 +109,17 @@ qva_to_vva(struct virtio_net *dev, uint64_t qemu_va) } -/* - * Retrieves an entry from the devices configuration linked list. - */ -static struct virtio_net_config_ll * -get_config_ll_entry(struct vhost_device_ctx ctx) -{ - struct virtio_net_config_ll *ll_dev = ll_root; - - /* Loop through linked list until the device_fh is found. */ - while (ll_dev != NULL) { - if (ll_dev->dev.device_fh == ctx.fh) - return ll_dev; - ll_dev = ll_dev->next; - } - - return NULL; -} - -/* - * Searches the configuration core linked list and - * retrieves the device if it exists. - */ struct virtio_net * get_device(struct vhost_device_ctx ctx) { - struct virtio_net_config_ll *ll_dev; + struct virtio_net *dev = vhost_devices[ctx.fh]; - ll_dev = get_config_ll_entry(ctx); - - if (ll_dev) - return &ll_dev->dev; - - RTE_LOG(ERR, VHOST_CONFIG, - "(%"PRIu64") Device not found in linked list.\n", ctx.fh); - return NULL; -} - -/* - * Add entry containing a device to the device configuration linked list. - */ -static void -add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev) -{ - struct virtio_net_config_ll *ll_dev = ll_root; - - /* If ll_dev == NULL then this is the first device so go to else */ - if (ll_dev) { - /* If the 1st device_fh != 0 then we insert our device here. */ - if (ll_dev->dev.device_fh != 0) { - new_ll_dev->dev.device_fh = 0; - new_ll_dev->next = ll_dev; - ll_root = new_ll_dev; - } else { - /* - * Increment through the ll until we find un unused - * device_fh. Insert the device at that entry. - */ - while ((ll_dev->next != NULL) && - (ll_dev->dev.device_fh == - (ll_dev->next->dev.device_fh - 1))) - ll_dev = ll_dev->next; - - new_ll_dev->dev.device_fh = ll_dev->dev.device_fh + 1; - new_ll_dev->next = ll_dev->next; - ll_dev->next = new_ll_dev; - } - } else { - ll_root = new_ll_dev; - ll_root->dev.device_fh = 0; + if (unlikely(!dev)) { + RTE_LOG(ERR, VHOST_CONFIG, + "(%"PRIu64") device not found.\n", ctx.fh); } + return dev; } static void @@ -219,43 +152,14 @@ cleanup_device(struct virtio_net *dev, int destroy) * Release virtqueues and device memory. */ static void -free_device(struct virtio_net_config_ll *ll_dev) +free_device(struct virtio_net *dev) { uint32_t i; - for (i = 0; i < ll_dev->dev.virt_qp_nb; i++) - rte_free(ll_dev->dev.virtqueue[i * VIRTIO_QNUM]); - - rte_free(ll_dev); -} + for (i = 0; i < dev->virt_qp_nb; i++) + rte_free(dev->virtqueue[i * VIRTIO_QNUM]); -/* - * Remove an entry from the device configuration linked list. - */ -static struct virtio_net_config_ll * -rm_config_ll_entry(struct virtio_net_config_ll *ll_dev, - struct virtio_net_config_ll *ll_dev_last) -{ - /* First remove the device and then clean it up. */ - if (ll_dev == ll_root) { - ll_root = ll_dev->next; - cleanup_device(&ll_dev->dev, 1); - free_device(ll_dev); - return ll_root; - } else { - if (likely(ll_dev_last != NULL)) { - ll_dev_last->next = ll_dev->next; - cleanup_device(&ll_dev->dev, 1); - free_device(ll_dev); - return ll_dev_last->next; - } else { - cleanup_device(&ll_dev->dev, 1); - free_device(ll_dev); - RTE_LOG(ERR, VHOST_CONFIG, - "Remove entry from config_ll failed\n"); - return NULL; - } - } + rte_free(dev); } static void @@ -353,23 +257,31 @@ reset_device(struct virtio_net *dev) int vhost_new_device(struct vhost_device_ctx ctx) { - struct virtio_net_config_ll *new_ll_dev; + struct virtio_net *dev; + int i; - /* Setup device and virtqueues. */ - new_ll_dev = rte_zmalloc(NULL, sizeof(struct virtio_net_config_ll), 0); - if (new_ll_dev == NULL) { + dev = rte_zmalloc(NULL, sizeof(struct virtio_net), 0); + if (dev == NULL) { RTE_LOG(ERR, VHOST_CONFIG, "(%"PRIu64") Failed to allocate memory for dev.\n", ctx.fh); return -1; } - new_ll_dev->next = NULL; + for (i = 0; i < MAX_VHOST_DEVICE; i++) { + if (vhost_devices[i] == NULL) + break; + } + if (i == MAX_VHOST_DEVICE) { + RTE_LOG(ERR, VHOST_CONFIG, + "Failed to find a free slot for new device.\n"); + return -1; + } - /* Add entry to device configuration linked list. */ - add_config_ll_entry(new_ll_dev); + vhost_devices[i] = dev; + dev->device_fh = i; - return new_ll_dev->dev.device_fh; + return i; } /* @@ -379,30 +291,15 @@ vhost_new_device(struct vhost_device_ctx ctx) void vhost_destroy_device(struct vhost_device_ctx ctx) { - struct virtio_net_config_ll *ll_dev_cur_ctx, *ll_dev_last = NULL; - struct virtio_net_config_ll *ll_dev_cur = ll_root; - - /* Find the linked list entry for the device to be removed. */ - ll_dev_cur_ctx = get_config_ll_entry(ctx); - while (ll_dev_cur != NULL) { - /* - * If the device is found or - * a device that doesn't exist is found then it is removed. - */ - if (ll_dev_cur == ll_dev_cur_ctx) { - /* - * If the device is running on a data core then call - * the function to remove it from the data core. - */ - if ((ll_dev_cur->dev.flags & VIRTIO_DEV_RUNNING)) - notify_ops->destroy_device(&(ll_dev_cur->dev)); - ll_dev_cur = rm_config_ll_entry(ll_dev_cur, - ll_dev_last); - } else { - ll_dev_last = ll_dev_cur; - ll_dev_cur = ll_dev_cur->next; - } - } + struct virtio_net *dev = get_device(ctx); + + if (dev->flags & VIRTIO_DEV_RUNNING) + notify_ops->destroy_device(dev); + + cleanup_device(dev, 1); + free_device(dev); + + vhost_devices[ctx.fh] = NULL; } void @@ -547,17 +444,17 @@ static struct virtio_net* numa_realloc(struct virtio_net *dev, int index) { int oldnode, newnode; - struct virtio_net_config_ll *old_ll_dev, *new_ll_dev = NULL; + struct virtio_net *old_dev, *new_dev = NULL; struct vhost_virtqueue *old_vq, *new_vq = NULL; int ret; int realloc_dev = 0, realloc_vq = 0; - old_ll_dev = (struct virtio_net_config_ll *)dev; - old_vq = dev->virtqueue[index]; + old_dev = dev; + old_vq = dev->virtqueue[index]; ret = get_mempolicy(&newnode, NULL, 0, old_vq->desc, MPOL_F_NODE | MPOL_F_ADDR); - ret = ret | get_mempolicy(&oldnode, NULL, 0, old_ll_dev, + ret = ret | get_mempolicy(&oldnode, NULL, 0, old_dev, MPOL_F_NODE | MPOL_F_ADDR); if (ret) { RTE_LOG(ERR, VHOST_CONFIG, @@ -581,36 +478,30 @@ numa_realloc(struct virtio_net *dev, int index) return dev; if (realloc_dev) - new_ll_dev = rte_malloc_socket(NULL, - sizeof(struct virtio_net_config_ll), 0, newnode); + new_dev = rte_malloc_socket(NULL, + sizeof(struct virtio_net), 0, newnode); if (realloc_vq) new_vq = rte_malloc_socket(NULL, sizeof(struct vhost_virtqueue), 0, newnode); - if (!new_ll_dev && !new_vq) + if (!new_dev && !new_vq) return dev; if (realloc_vq) memcpy(new_vq, old_vq, sizeof(*new_vq)); if (realloc_dev) - memcpy(new_ll_dev, old_ll_dev, sizeof(*new_ll_dev)); - (new_ll_dev ? new_ll_dev : old_ll_dev)->dev.virtqueue[index] = + memcpy(new_dev, old_dev, sizeof(*new_dev)); + + (new_dev ? new_dev : old_dev)->virtqueue[index] = new_vq ? new_vq : old_vq; if (realloc_vq) rte_free(old_vq); if (realloc_dev) { - if (ll_root == old_ll_dev) - ll_root = new_ll_dev; - else { - struct virtio_net_config_ll *prev = ll_root; - while (prev->next != old_ll_dev) - prev = prev->next; - prev->next = new_ll_dev; - new_ll_dev->next = old_ll_dev->next; - } - rte_free(old_ll_dev); + rte_free(old_dev); + + vhost_devices[new_dev->device_fh] = new_dev; } - return realloc_dev ? &new_ll_dev->dev : dev; + return realloc_dev ? new_dev : dev; } #else static struct virtio_net*