Re: [PATCH tip/core/rcu 0/52] Remove rcu_state pointers for v4.20/v5.0

From: Paul E. McKenney
Date: Wed Aug 29 2018 - 23:22:26 EST


On Wed, Aug 29, 2018 at 10:00:26PM -0400, Steven Rostedt wrote:
> On Wed, 29 Aug 2018 15:38:30 -0700
> "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
>
> > Hello!
> >
> > This commit does RCU-consolidation cleanups that get rid of pointers to
> > the sole remaining rcu_state structure:
> >
> > 1-40: Remove the "rsp" parameter from numerous functions, given that
> > the corresponding argument will always be &rcu_state.
>
> Hmm, couldn't 1-40 have been made into a single patch?

They could. I separated them to make finding the inevitable typos easier.
But at this point, it is easy enough to squash them together, though.

Thanx, Paul

> -- Steve
>
> >
> > 41. Remove rcu_data structure's ->rsp field, now that it always
> > contains a pointer to rcu_state.
> >
> > 42. Remove non-flavor-traversal rsp local variable from tree_plugin.h.
> >
> > 43. Remove the for_each_rcu_flavor() flavor-traversal macro, given
> > that there is now only ever one flavor to traverse.
> >
> > 44. Simplify rcutorture_get_gp_data() based on there now being only
> > one rcu_state structure.
> >
> > 45. Restructure rcu_check_gp_kthread_starvation() based on there
> > now being only one rcu_state structure.
> >
> > 46. Restructure RCU CPU stall warnings based on there now being only
> > one rcu_state structure.
> >
> > 47. Restructure grace-period management code based on there now being
> > only one rcu_state structure.
> >
> > 48. Restructure callback registration/invocation code based on there
> > now being only one rcu_state structure.
> >
> > 49. Restructure quiescent-state and grace-period-nonstart code based
> > on there now being only one rcu_state structure.
> >
> > 50. Restructure rcu_barrier() based on there now being only one
> > rcu_state structure.
> >
> > 51. Restructure initialization code based on there now being only
> > one rcu_state structure.
> >
> > 52. Fix typo in force_qs_rnp()'s parameter's parameter, which was
> > located by searching for "rsp".
> >
> > Thanx, Paul
> >
> > ------------------------------------------------------------------------
> >
> > Documentation/RCU/Design/Data-Structures/Data-Structures.html | 23
> > kernel/rcu/rcu.h | 28
> > kernel/rcu/srcutree.c | 4
> > kernel/rcu/tree.c | 1261 ++++------
> > kernel/rcu/tree.h | 29
> > kernel/rcu/tree_exp.h | 209 -
> > kernel/rcu/tree_plugin.h | 203 -
> > 7 files changed, 784 insertions(+), 973 deletions(-)
>