netdev - Re: [PATCH net] tcp: tcp_get_info() should read tcp_time

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Date:   Thu, 16 Mar 2017 21:37:37 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     eric.dumazet@...il.com
Cc:     netdev@...r.kernel.org
Subject: Re: [PATCH net] tcp: tcp_get_info() should read tcp_time_stamp
 later

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Thu, 16 Mar 2017 15:43:19 -0700

> From: Eric Dumazet <edumazet@...gle.com>
> 
> Commit b369e7fd41f7 ("tcp: make TCP_INFO more consistent") moved
> lock_sock_fast() earlier in tcp_get_info()
> 
> This has the minor effect that jiffies value being sampled at the
> beginning of tcp_get_info() is more likely to be off by one, and we
> report big tcpi_last_data_sent values (like 0xFFFFFFFF).
> 
> Since we lock the socket, fetching tcp_time_stamp right before
> doing the jiffies_to_msecs() calls is enough to remove these
> wrong values.
> 
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>

Applied, thanks Eric.