• Tejun Heo's avatar
    fs/writeback, rcu: Don't use list_entry_rcu() for pointer offsetting in bdi_split_work_to_wbs() · b33e18f6
    Tejun Heo authored
    bdi_split_work_to_wbs() uses list_for_each_entry_rcu_continue()
    to walk @bdi->wb_list.  To set up the initial iteration
    condition, it uses list_entry_rcu() to calculate the entry
    pointer corresponding to the list head; however, this isn't an
    actual RCU dereference and using list_entry_rcu() for it ended
    up breaking a proposed list_entry_rcu() change because it was
    feeding an non-lvalue pointer into the macro.
    
    Don't use the RCU variant for simple pointer offsetting.  Use
    list_entry() instead.
    Reported-by: default avatarIngo Molnar <mingo@kernel.org>
    Signed-off-by: default avatarTejun Heo <tj@kernel.org>
    Cc: Darren Hart <dvhart@linux.intel.com>
    Cc: David Howells <dhowells@redhat.com>
    Cc: Dipankar Sarma <dipankar@in.ibm.com>
    Cc: Eric Dumazet <edumazet@google.com>
    Cc: Frederic Weisbecker <fweisbec@gmail.com>
    Cc: Josh Triplett <josh@joshtriplett.org>
    Cc: Lai Jiangshan <jiangshanlai@gmail.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
    Cc: Oleg Nesterov <oleg@redhat.com>
    Cc: Patrick Marlier <patrick.marlier@gmail.com>
    Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Steven Rostedt <rostedt@goodmis.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: pranith kumar <bobby.prani@gmail.com>
    Link: http://lkml.kernel.org/r/20151027051939.GA19355@mtj.duckdns.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    b33e18f6
fs-writeback.c 67.2 KB