From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754399Ab0AECEn (ORCPT ); Mon, 4 Jan 2010 21:04:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754293Ab0AECEU (ORCPT ); Mon, 4 Jan 2010 21:04:20 -0500 Received: from e9.ny.us.ibm.com ([32.97.182.139]:40284 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754162Ab0AECEQ (ORCPT ); Mon, 4 Jan 2010 21:04:16 -0500 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: 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, "Paul E. McKenney" , Alexander Viro Subject: [PATCH tip/core/rcu 6/8] vfs: apply lockdep-based checking to rcu_dereference() uses Date: Mon, 4 Jan 2010 18:04:09 -0800 Message-Id: <12626570514009-git-send-email-> X-Mailer: git-send-email 1.5.2.5 In-Reply-To: <20100105020345.GA32114@linux.vnet.ibm.com> References: <20100105020345.GA32114@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paul E. McKenney Add lockdep-ified RCU primitives to alloc_fd(), files_fdtable() and fcheck_files(). Cc: Alexander Viro Signed-off-by: Paul E. McKenney --- fs/file.c | 2 +- include/linux/fdtable.h | 7 +++++-- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/file.c b/fs/file.c index f313314..c506bc6 100644 --- a/fs/file.c +++ b/fs/file.c @@ -477,7 +477,7 @@ repeat: error = fd; #if 1 /* Sanity check */ - if (rcu_dereference(fdt->fd[fd]) != NULL) { + if (rcu_dereference_raw(fdt->fd[fd]) != NULL) { printk(KERN_WARNING "alloc_fd: slot %d not NULL!\n", fd); rcu_assign_pointer(fdt->fd[fd], NULL); } diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h index a2ec74b..e498a0c 100644 --- a/include/linux/fdtable.h +++ b/include/linux/fdtable.h @@ -57,7 +57,10 @@ struct files_struct { struct file * fd_array[NR_OPEN_DEFAULT]; }; -#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))) struct file_operations; struct vfsmount; @@ -78,7 +81,7 @@ 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)); return file; } -- 1.5.2.5