Re: [PATCH] rcu: Convert timers to use timer_setup()

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Wed, Oct 25, 2017 at 04:17:32PM +0200, Kees Cook wrote:
> Sorry, I sent this and forgot that timer_setup_on_stack() is only in
> -next. If this patch is okay, I can carry it in the timers tree.

Given the fixes I called out, I am fine with your carrying it separately.

							Thanx, Paul

> Thanks!
> 
> -Kees
> 
> On Tue, Oct 24, 2017 at 11:32 AM, Kees Cook <keescook@chromium.org> wrote:
> > In preparation for unconditionally passing the struct timer_list pointer to
> > all timer callbacks, switch to using the new timer_setup() and from_timer()
> > to pass the timer pointer explicitly.
> >
> > Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
> > Cc: Josh Triplett <josh@joshtriplett.org>
> > Cc: Steven Rostedt <rostedt@goodmis.org>
> > Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > Cc: Lai Jiangshan <jiangshanlai@gmail.com>
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > ---
> >  kernel/rcu/rcutorture.c  | 4 ++--
> >  kernel/rcu/tree_plugin.h | 9 +++++----
> >  2 files changed, 7 insertions(+), 6 deletions(-)
> >
> > diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> > index e1d3fa534ac0..b6fbbeb5a7da 100644
> > --- a/kernel/rcu/rcutorture.c
> > +++ b/kernel/rcu/rcutorture.c
> > @@ -1078,7 +1078,7 @@ static void rcu_torture_timer_cb(struct rcu_head *rhp)
> >   * counter in the element should never be greater than 1, otherwise, the
> >   * RCU implementation is broken.
> >   */
> > -static void rcu_torture_timer(unsigned long unused)
> > +static void rcu_torture_timer(struct timer_list *unused)
> >  {
> >         int idx;
> >         unsigned long started;
> > @@ -1165,7 +1165,7 @@ rcu_torture_reader(void *arg)
> >         VERBOSE_TOROUT_STRING("rcu_torture_reader task started");
> >         set_user_nice(current, MAX_NICE);
> >         if (irqreader && cur_ops->irq_capable)
> > -               setup_timer_on_stack(&t, rcu_torture_timer, 0);
> > +               timer_setup_on_stack(&t, rcu_torture_timer, 0);
> >
> >         do {
> >                 if (irqreader && cur_ops->irq_capable) {
> > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> > index 8a5a3f9b1250..5fb7beee76aa 100644
> > --- a/kernel/rcu/tree_plugin.h
> > +++ b/kernel/rcu/tree_plugin.h
> > @@ -2265,9 +2265,11 @@ static void do_nocb_deferred_wakeup_common(struct rcu_data *rdp)
> >  }
> >
> >  /* Do a deferred wakeup of rcu_nocb_kthread() from a timer handler. */
> > -static void do_nocb_deferred_wakeup_timer(unsigned long x)
> > +static void do_nocb_deferred_wakeup_timer(struct timer_list *t)
> >  {
> > -       do_nocb_deferred_wakeup_common((struct rcu_data *)x);
> > +       struct rcu_data *x = from_timer(x, t, nocb_timer);
> > +
> > +       do_nocb_deferred_wakeup_common(x);
> >  }
> >
> >  /*
> > @@ -2331,8 +2333,7 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)
> >         init_swait_queue_head(&rdp->nocb_wq);
> >         rdp->nocb_follower_tail = &rdp->nocb_follower_head;
> >         raw_spin_lock_init(&rdp->nocb_lock);
> > -       setup_timer(&rdp->nocb_timer, do_nocb_deferred_wakeup_timer,
> > -                   (unsigned long)rdp);
> > +       timer_setup(&rdp->nocb_timer, do_nocb_deferred_wakeup_timer, 0);
> >  }
> >
> >  /*
> > --
> > 2.7.4
> >
> >
> > --
> > Kees Cook
> > Pixel Security
> 
> 
> 
> -- 
> Kees Cook
> Pixel Security
>