Re: [PATCH 3/3] block/nbd: nbd_co_reconnect_loop(): don't sleep if drained

[Eric Blake]

On 7/20/20 4:00 AM, Vladimir Sementsov-Ogievskiy wrote:
> We try to go to wakeable sleep, so that, if drain begins it will break
> the sleep. But what if nbd_client_co_drain_begin() already called and
> s->drained is already true? We'll go to sleep, and drain will have to
> wait for the whole timeout. Let's improve it.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>   block/nbd.c | 11 ++++++-----
>   1 file changed, 6 insertions(+), 5 deletions(-)

How frequently did you hit this case?  At any rate, the optimization 
looks sane, and I'm happy to include it in 5.1.

Reviewed-by: Eric Blake <eblake@redhat.com>

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Eric Blake, Principal Software Engineer
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