From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v2 1/2] eal: add uevent api for hot plug
Date: Wed, 05 Jul 2017 01:45:09 +0200
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Cc: dev@dpdk.org, helin.zhang@intel.com, jingjing.wu@intel.com
To: Jeff Guo <jia.guo@intel.com>
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Hi,

This is an interesting step for hotplug in DPDK.

28/06/2017 13:07, Jeff Guo:
> +       netlink_fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);

It is monitoring the whole system...

> +int
> +rte_uevent_get(int fd, struct rte_uevent *uevent)
> +{
> +       int ret;
> +       char buf[RTE_UEVENT_MSG_LEN];
> +
> +       memset(uevent, 0, sizeof(struct rte_uevent));
> +       memset(buf, 0, RTE_UEVENT_MSG_LEN);
> +
> +       ret = recv(fd, buf, RTE_UEVENT_MSG_LEN - 1, MSG_DONTWAIT);

... and it is read from this function called by one driver.
It cannot work without a global dispatch.

It must be a global mechanism, probably a service core.
The question is also to know whether it should be a mandatory
service in DPDK or an optional helper?