From: Peter Zijlstra <peterz@infradead.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org, mingo@elte.hu,
laijs@cn.fujitsu.com, dipankar@in.ibm.com,
akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca,
josh@joshtriplett.org, dvhltc@us.ibm.com, niv@us.ibm.com,
tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org,
Valdis.Kletnieks@vt.edu, dhowells@redhat.com,
Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH tip/core/rcu 07/13] vfs: apply lockdep-based checking to rcu_dereference() uses
Date: Sun, 14 Feb 2010 11:12:10 +0100 [thread overview]
Message-ID: <1266142330.5273.414.camel@laptop> (raw)
In-Reply-To: <1265932839-25899-7-git-send-email-paulmck@linux.vnet.ibm.com>
On Thu, 2010-02-11 at 16:00 -0800, Paul E. McKenney wrote:
>
> -#define files_fdtable(files) (rcu_dereference((files)->fdt))
> +#define files_fdtable(files) \
> + (rcu_dereference_check((files)->fdt, \
> + rcu_read_lock_held() || \
> + lockdep_is_held(&(files)->file_lock) ||
> \
> + atomic_read(&files->count) == 1))
>
> struct file_operations;
> struct vfsmount;
> @@ -78,7 +82,7 @@ static inline struct file * fcheck_files(struct files_struct *files, unsigned in
> struct fdtable *fdt = files_fdtable(files);
>
> if (fd < fdt->max_fds)
> - file = rcu_dereference(fdt->fd[fd]);
> + file = rcu_dereference_check(fdt->fd[fd], rcu_read_lock_held() || lockdep_is_held(&files->file_lock) || atomic_read(&files->count) == 1);
> return file;
I'm almost thinking you can do something smart here and not replicate
that condition :-)
next prev parent reply other threads:[~2010-02-14 10:12 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-12 0:00 [PATCH tip/core/rcu 0/13] rcu: add lockdep checking, doc update, dyntick GP acceleration Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 01/13] rcu: introduce lockdep-based checking to RCU read-side primitives Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 02/13] rcu: add lockdep-enabled variants of rcu_dereference() Paul E. McKenney
2010-02-12 4:13 ` Eric Dumazet
2010-02-12 0:00 ` [PATCH tip/core/rcu 03/13] rcu: integrate rcu_dereference_check() message into lockdep Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 04/13] rcu: disable lockdep checking in RCU list-traversal primitives Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 05/13] net: add checking to rcu_dereference() primitives Paul E. McKenney
2010-02-12 4:15 ` Eric Dumazet
2010-02-14 8:23 ` Ingo Molnar
2010-02-15 7:18 ` David Miller
2010-02-14 8:34 ` Michał Mirosław
2010-02-14 8:34 ` Michał Mirosław
2010-02-14 8:50 ` Eric Dumazet
2010-02-12 0:00 ` [PATCH tip/core/rcu 06/13] sched: use lockdep-based checking on rcu_dereference() Paul E. McKenney
2010-02-14 10:12 ` Peter Zijlstra
2010-02-14 17:48 ` Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 07/13] vfs: apply lockdep-based checking to rcu_dereference() uses Paul E. McKenney
2010-02-14 10:12 ` Peter Zijlstra [this message]
2010-02-14 17:37 ` Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 08/13] radix-tree: disable RCU lockdep checking in radix tree Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 09/13] idr: apply lockdep-based diagnostics to rcu_dereference() uses Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 10/13] security: apply lockdep-based checking " Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 11/13] rcu: documentation update for CONFIG_PROVE_RCU Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 12/13] rcu: fix citation of Mathieu's dissertation Paul E. McKenney
2010-02-12 0:00 ` [PATCH tip/core/rcu 13/13] rcu: accelerate grace period if last non-dynticked CPU Paul E. McKenney
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