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From: David Miller <davem@davemloft.net>
To: saeedm@mellanox.com
Cc: netdev@vger.kernel.org
Subject: Re: [RFC net-next 2/2] net: net-sysfs: Reduce netstat_show read_lock critical section
Date: Tue, 10 Apr 2018 13:17:26 -0400 (EDT)	[thread overview]
Message-ID: <20180410.131726.489974712859296224.davem@davemloft.net> (raw)
In-Reply-To: <20180410170812.18905-2-saeedm@mellanox.com>

From: Saeed Mahameed <saeedm@mellanox.com>
Date: Tue, 10 Apr 2018 10:08:12 -0700

> Instead of holding the device chain read_lock also while calling
> dev_get_stats just hold it only to check dev_isalive, if the dev is alive,
> hold that dev via dev_hold then release the read_lock.
> 
> When done handling the device, dev_put it.
> 
> Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

My feedback here is that same as for patch #1.

Two atomics for a shorter RCU lock hold time is not that great of
a tradeoff.

  reply	other threads:[~2018-04-10 17:17 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-10 17:08 [RFC net-next 1/2] net: net-porcfs: Reduce rcu lock critical section Saeed Mahameed
2018-04-10 17:08 ` [RFC net-next 2/2] net: net-sysfs: Reduce netstat_show read_lock " Saeed Mahameed
2018-04-10 17:17   ` David Miller [this message]
2018-04-10 17:16 ` [RFC net-next 1/2] net: net-porcfs: Reduce rcu lock " David Miller
2018-04-10 20:35   ` Eric Dumazet
2018-04-11 18:59     ` Saeed Mahameed
2018-04-11 22:30       ` Eric Dumazet
2018-04-11 23:47         ` Saeed Mahameed
2018-04-12  2:59           ` Eric Dumazet
2018-04-12 19:12             ` Saeed Mahameed
2018-04-16 20:50               ` Saeed Mahameed
2018-04-16 21:07                 ` Eric Dumazet

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