netdev - napi: SCHED flag set/clear

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Date:   Sat, 23 Jun 2018 03:52:55 +0530
From:   Krishna Chaitanya <chaitanya.mgit@...il.com>
To:     netdev <netdev@...r.kernel.org>
Subject: napi: SCHED flag set/clear

Hi,

While debugging a NAPI related issue (calling napi_disable() twice
leading to deadlock),
I have come across below query. The issue is not documented anywhere
(except for Ben grear's  ath10k patch)

Below are my expectations:

napi_disable(): waits for SCHED (ignoring other flags)
napi_enable(): set SCHED flag

but in reality,

napi_disable: test and set SCHED flag in a while() loop?
napi_enable: clear SCHED flag

This is a bit counter-intuitive, SCHED generally means pollable (enabled).

Am i missing something?

--
Thanks,
Regards,
Chaitanya T K.