From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH V9 1/5] eal: add uevent monitor api and
	callback func
Date: Wed, 10 Jan 2018 08:34:39 -0800
Message-ID: <20180110083439.0a9f4fe8@xeon-e3>
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Cc: bruce.richardson@intel.com, ferruh.yigit@intel.com,
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To: Jeff Guo <jia.guo@intel.com>
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On Wed, 10 Jan 2018 17:12:20 +0800
Jeff Guo <jia.guo@intel.com> wrote:

> +static int
> +dev_monitor_fd_new(void)
> +{
> +
> +	int uevent_fd;
> +
> +	uevent_fd = socket(PF_NETLINK, SOCK_RAW | SOCK_CLOEXEC |
> +			SOCK_NONBLOCK,
> +			NETLINK_KOBJECT_UEVENT);
> +	if (uevent_fd < 0) {

If you used a blocking socket, then epoll would not be necessary.
There is one netlink socket for whole system, and the thread is only
reading from one fd.