From: Jarek Poplawski <jarkao2@gmail.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next-2.6] net: introduce rcu_dereference_read_lock_or_rtnl
Date: Tue, 07 Sep 2010 22:49:28 +0200 [thread overview]
Message-ID: <4C86A558.6030802@gmail.com> (raw)
In-Reply-To: <1283890291.2634.143.camel@edumazet-laptop>
Eric Dumazet wrote, On 09/07/2010 10:11 PM:
> We use rcu_dereference_check(p, rcu_read_lock_held() ||
> lockdep_rtnl_is_held()) several times in network stack.
>
> More usages to come too, so its time to create a helper.
>
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> ---
> include/linux/rtnetlink.h | 12 ++++++++++++
>
> diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
> index 58d4449..5ba48bb 100644
> --- a/include/linux/rtnetlink.h
> +++ b/include/linux/rtnetlink.h
> @@ -745,10 +745,22 @@ extern void rtnl_lock(void);
> extern void rtnl_unlock(void);
> extern int rtnl_trylock(void);
> extern int rtnl_is_locked(void);
> +
> #ifdef CONFIG_PROVE_LOCKING
> extern int lockdep_rtnl_is_held(void);
> #endif /* #ifdef CONFIG_PROVE_LOCKING */
>
> +/**
> + * rcu_dereference_read_lock_or_rtnl - rcu_dereference with debug checking
> + * @p: The pointer to read, prior to dereferencing
> + *
> + * Do an rcu_dereference(p), but check caller either holds rcu_read_lock()
> + * or RTNL
> + */
> +#define rcu_dereference_read_lock_or_rtnl(p)
My proposal is to shorten the name, and since rcu_read_lock
part seems obvious, maybe rcu_dereference_rtnl() only?
Jarek P.
\
> + rcu_dereference_check(p, rcu_read_lock_held() || \
> + lockdep_rtnl_is_held());
> +
> extern void rtnetlink_init(void);
> extern void __rtnl_unlock(void);
>
>
>
> --
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>
next prev parent reply other threads:[~2010-09-07 20:49 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-07 20:11 [PATCH net-next-2.6] net: introduce rcu_dereference_read_lock_or_rtnl Eric Dumazet
2010-09-07 20:49 ` Jarek Poplawski [this message]
2010-09-07 21:07 ` [PATCH net-next-2.6] net: introduce rcu_dereference_rtnl Eric Dumazet
2010-09-08 18:29 ` Ben Hutchings
2010-09-08 18:44 ` Eric Dumazet
2010-09-08 21:15 ` David Miller
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