>Subject: [dpdk-dev] [PATCH] net/vdev_netvsc: handle removal of associated
>pci device
>
>The vdev_netvsc was not detecting when the associated PCI device
>(SRIOV) was removed. Because of that it would keep feeding the same
>(removed) device to failsafe PMD which would then unsuccessfully try and
>probe for it.
>
>Change to use a mark/sweep method to detect that PCI device was removed,
>and also only tell failsafe about new PCI devices.
>Vdev_netvsc does not have to keep stuffing the pipe with the same already
>existing PCI device.
>
>Fixes: e7dc5d7becc5 ("net/vdev_netvsc: implement core functionality")
>Cc: ma...@mellanox.com, sta...@dpdk.org
>Signed-off-by: Stephen Hemminger <step...@networkplumber.org>
Reviewed-by: Long Li <lon...@microsoft.com>
>---
> drivers/net/vdev_netvsc/vdev_netvsc.c | 39 +++++++++++++++++++++++--
>--
> 1 file changed, 34 insertions(+), 5 deletions(-)
>
>diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c
>b/drivers/net/vdev_netvsc/vdev_netvsc.c
>index 1ecb0b3e6a34..80a3158012ce 100644
>--- a/drivers/net/vdev_netvsc/vdev_netvsc.c
>+++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
>@@ -66,6 +66,7 @@ struct vdev_netvsc_ctx {
> char devargs[256]; /**< Fail-safe device arguments. */
> char if_name[IF_NAMESIZE]; /**< NetVSC netdevice name. */
> unsigned int if_index; /**< NetVSC netdevice index. */
>+ int pci_found; /**< Device detection */
> struct rte_ether_addr if_addr; /**< NetVSC MAC address. */
> int pipe[2]; /**< Fail-safe communication pipe.
>*/
> char yield[256]; /**< PCI sub-device arguments. */
>@@ -405,11 +406,18 @@ vdev_netvsc_device_probe(const struct
>if_nameindex *iface,
> len = strlen(addr);
> if (!len)
> return 0;
>+
>+ ctx->pci_found = 1;
>+
>+ /* Skip if this is same device already sent to failsafe */
>+ if (strcmp(addr, ctx->yield) == 0)
>+ return 0;
>+
>+ DRV_LOG(DEBUG, "associating PCI device \"%s\" with NetVSC"
>+ " interface \"%s\" (index %u)", addr, ctx->if_name,
>+ ctx->if_index);
>+
> /* Send PCI device argument to fail-safe PMD instance. */
>- if (strcmp(addr, ctx->yield))
>- DRV_LOG(DEBUG, "associating PCI device \"%s\" with
>NetVSC"
>- " interface \"%s\" (index %u)", addr, ctx->if_name,
>- ctx->if_index);
> memmove(buf, addr, len + 1);
> addr = buf;
> buf[len] = '\n';
>@@ -452,12 +460,33 @@ vdev_netvsc_alarm(__rte_unused void *arg)
> struct vdev_netvsc_ctx *ctx;
> int ret;
>
>+ /* 1st pass: clear PCI flag on all devices */
>+ LIST_FOREACH(ctx, &vdev_netvsc_ctx_list, entry) {
>+ ctx->pci_found = 0;
>+ }
>+
>+ /* 2nd pass: scan all system devices to look for changes to this
>+device */
> LIST_FOREACH(ctx, &vdev_netvsc_ctx_list, entry) {
> ret =
>vdev_netvsc_foreach_iface(vdev_netvsc_device_probe, 0,
> ctx);
>- if (ret < 0)
>+
>+ if (ret < 0) {
>+ DRV_LOG(NOTICE, "can not scan devices for %s\n",
>+ ctx->if_name);
> break;
>+ }
> }
>+
>+ /* 3rd pass: detect PCI removal */
>+ LIST_FOREACH(ctx, &vdev_netvsc_ctx_list, entry) {
>+ if (!ctx->pci_found && ctx->yield[0]) {
>+ DRV_LOG(DEBUG, "disassociating PCI device \"%s\"
>from NetVSC"
>+ " interface \"%s\" (index %u)", ctx->yield, ctx-
>>if_name,
>+ ctx->if_index);
>+ ctx->yield[0] = '\0';
>+ }
>+ }
>+
> if (!vdev_netvsc_ctx_count)
> return;
> ret = rte_eal_alarm_set(VDEV_NETVSC_PROBE_MS * 1000,
>--
>2.27.0
