Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Mon, Jan 23, 2017 at 07:12:03PM +1100, Michael Ellerman wrote: > "Paul E. McKenney" writes: > > > On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: > >> On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > >> > * Paul E. McKenney

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Mon, Jan 23, 2017 at 07:12:03PM +1100, Michael Ellerman wrote: > "Paul E. McKenney" writes: > > > On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: > >> On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > >> > * Paul E. McKenney wrote: > > > > [ . . . ] > > > >> >

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

"Paul E. McKenney" writes: > On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: >> On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: >> > * Paul E. McKenney wrote: > > [ . . . ] > >> > > + */ >> > > +#ifdef

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

"Paul E. McKenney" writes: > On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: >> On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: >> > * Paul E. McKenney wrote: > > [ . . . ] > >> > > + */ >> > > +#ifdef CONFIG_PPC >> > > +#define smp_mb__after_unlock_lock()

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > On Sun, Jan 15, 2017 at 10:40:58AM +0100, Ingo Molnar wrote: > > > > * Paul E. McKenney wrote: > > > > > > [sounds of rummaging around in the Git tree] > > > > > > > > I found this commit of yours from

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > On Sun, Jan 15, 2017 at 10:40:58AM +0100, Ingo Molnar wrote: > > > > * Paul E. McKenney wrote: > > > > > > [sounds of rummaging around in the Git tree] > > > > > > > > I found this commit of yours from ancient history (more than a year > > > > ago!): > > > > >

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 10:40:58AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > > [sounds of rummaging around in the Git tree] > > > > > > I found this commit of yours from ancient history (more than a year ago!): > > > > > > commit

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 10:40:58AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > > [sounds of rummaging around in the Git tree] > > > > > > I found this commit of yours from ancient history (more than a year ago!): > > > > > > commit 12d560f4ea87030667438a169912380be00cea4b

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > > [sounds of rummaging around in the Git tree] > > > > I found this commit of yours from ancient history (more than a year ago!): > > > > commit 12d560f4ea87030667438a169912380be00cea4b > > Author: Paul E. McKenney

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > > [sounds of rummaging around in the Git tree] > > > > I found this commit of yours from ancient history (more than a year ago!): > > > > commit 12d560f4ea87030667438a169912380be00cea4b > > Author: Paul E. McKenney > > Date: Tue Jul 14 18:35:23 2015 -0700

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 08:57:11AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > > > > > * Paul E. McKenney wrote: > > > > > > > diff --git

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 08:57:11AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > > > > > * Paul E. McKenney wrote: > > > > > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > > > index

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > > > * Paul E. McKenney wrote: > > > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > > index 357b32aaea48..5fdfe874229e

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > > > * Paul E. McKenney wrote: > > > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > > index 357b32aaea48..5fdfe874229e 100644 > > > --- a/include/linux/rcupdate.h > > > +++

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > index 357b32aaea48..5fdfe874229e 100644 > > --- a/include/linux/rcupdate.h > > +++

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sun, Jan 15, 2017 at 08:11:23AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > > index 357b32aaea48..5fdfe874229e 100644 > > --- a/include/linux/rcupdate.h > > +++ b/include/linux/rcupdate.h > > @@ -1175,11

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > index 357b32aaea48..5fdfe874229e 100644 > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -1175,11 +1175,11 @@ do { \ > * if the UNLOCK and LOCK are

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > index 357b32aaea48..5fdfe874229e 100644 > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -1175,11 +1175,11 @@ do { \ > * if the UNLOCK and LOCK are executed by the same CPU or

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > > > + */ > > > +#ifdef CONFIG_PPC > > > +#define smp_mb__after_unlock_lock() smp_mb() /* Full ordering for > > > lock. */ > > > +#else /* #ifdef CONFIG_PPC */ > > > +#define smp_mb__after_unlock_lock() do { } while (0) > > >

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > > > + */ > > > +#ifdef CONFIG_PPC > > > +#define smp_mb__after_unlock_lock() smp_mb() /* Full ordering for > > > lock. */ > > > +#else /* #ifdef CONFIG_PPC */ > > > +#define smp_mb__after_unlock_lock() do { } while (0) > > > +#endif /* #else #ifdef

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > If a process invokes synchronize_srcu(), is delayed just the right amount > > of time, and thus does not sleep when waiting for the grace period to > > complete, there is

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: > > > If a process invokes synchronize_srcu(), is delayed just the right amount > > of time, and thus does not sleep when waiting for the grace period to > > complete, there is no ordering between the end

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: > On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: [ . . . ] > > > + */ > > > +#ifdef CONFIG_PPC > > > +#define smp_mb__after_unlock_lock() smp_mb() /*

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

On Sat, Jan 14, 2017 at 11:54:17AM -0800, Paul E. McKenney wrote: > On Sat, Jan 14, 2017 at 10:35:50AM +0100, Ingo Molnar wrote: > > * Paul E. McKenney wrote: [ . . . ] > > > + */ > > > +#ifdef CONFIG_PPC > > > +#define smp_mb__after_unlock_lock() smp_mb() /* Full ordering for > > >

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > If a process invokes synchronize_srcu(), is delayed just the right amount > of time, and thus does not sleep when waiting for the grace period to > complete, there is no ordering between the end of the grace period and > the code following

Re: [PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

* Paul E. McKenney wrote: > If a process invokes synchronize_srcu(), is delayed just the right amount > of time, and thus does not sleep when waiting for the grace period to > complete, there is no ordering between the end of the grace period and > the code following the synchronize_srcu().

[PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

If a process invokes synchronize_srcu(), is delayed just the right amount of time, and thus does not sleep when waiting for the grace period to complete, there is no ordering between the end of the grace period and the code following the synchronize_srcu(). Similarly, there can be a lack of

[PATCH tip/core/rcu 2/3] srcu: Force full grace-period ordering

If a process invokes synchronize_srcu(), is delayed just the right amount of time, and thus does not sleep when waiting for the grace period to complete, there is no ordering between the end of the grace period and the code following the synchronize_srcu(). Similarly, there can be a lack of