linux-stable.git/kernel/rcu/tree_plugin.h, branch v4.12.2

rcu: Open-code the rcu_cblist_n_lazy_cbs() function

2017-05-02T16:22:48+00:00

Because the rcu_cblist_n_lazy_cbs() just samples the ->len_lazy counter,
and because the rcu_cblist structure is quite straightforward, it makes
sense to open-code rcu_cblist_n_lazy_cbs(p) as p->len_lazy, cutting out
a level of indirection.  This commit makes this change.

Reported-by: Ingo Molnar 
Signed-off-by: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Linus Torvalds

rcu: Open-code the rcu_cblist_n_cbs() function

2017-05-02T16:21:59+00:00

Because the rcu_cblist_n_cbs() just samples the ->len counter, and
because the rcu_cblist structure is quite straightforward, it makes
sense to open-code rcu_cblist_n_cbs(p) as p->len, cutting out a level
of indirection.  This commit makes this change.

Reported-by: Ingo Molnar 
Signed-off-by: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Linus Torvalds

rcu: Open-code the rcu_cblist_empty() function

2017-05-02T15:18:40+00:00

Because the rcu_cblist_empty() just samples the ->head pointer, and
because the rcu_cblist structure is quite straightforward, it makes
sense to open-code rcu_cblist_empty(p) as !p->head, cutting out a
level of indirection.  This commit makes this change.

Reported-by: Ingo Molnar 
Signed-off-by: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Linus Torvalds

Merge branches 'doc.2017.04.12a', 'fixes.2017.04.19a' and 'srcu.2017.04.21a' into HEAD

2017-04-21T13:00:13+00:00

doc.2017.04.12a: Documentation updates
fixes.2017.04.19a: Miscellaneous fixes
srcu.2017.04.21a: Parallelize SRCU callback handling

rcu: Use true/false in assignment to bool

2017-04-19T16:29:20+00:00

This commit makes the parse_rcu_nocb_poll() function assign true
(rather than the constant 1) to the bool variable rcu_nocb_poll.

Signed-off-by: Nicholas Mc Guire 
Signed-off-by: Paul E. McKenney

srcu: Abstract multi-tail callback list handling

2017-04-18T18:38:18+00:00

RCU has only one multi-tail callback list, which is implemented via
the nxtlist, nxttail, nxtcompleted, qlen_lazy, and qlen fields in the
rcu_data structure, and whose operations are open-code throughout the
Tree RCU implementation.  This has been more or less OK in the past,
but upcoming callback-list optimizations in SRCU could really use
a multi-tail callback list there as well.

This commit therefore abstracts the multi-tail callback list handling
into a new kernel/rcu/rcu_segcblist.h file, and uses this new API.
The simple head-and-tail pointer callback list is also abstracted and
applied everywhere except for the NOCB callback-offload lists.  (Yes,
the plan is to apply them there as well, but this commit is already
bigger than would be good.)

Signed-off-by: Paul E. McKenney

rcu: Place guard on rcu_all_qs() and rcu_note_context_switch() actions

2017-04-18T18:38:18+00:00

The rcu_all_qs() and rcu_note_context_switch() do a series of checks,
taking various actions to supply RCU with quiescent states, depending
on the outcomes of the various checks.  This is a bit much for scheduling
fastpaths, so this commit creates a separate ->rcu_urgent_qs field in
the rcu_dynticks structure that acts as a global guard for these checks.
Thus, in the common case, rcu_all_qs() and rcu_note_context_switch()
check the ->rcu_urgent_qs field, find it false, and simply return.

Signed-off-by: Paul E. McKenney 
Cc: Peter Zijlstra

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:34+00:00

We are going to split  out of , which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder  file that just
maps to  to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:27+00:00

We are going to move scheduler ABI details to ,
which will be used from a number of .c files.

Create empty placeholder header that maps to .

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

Merge branches 'doc.2017.01.15b', 'dyntick.2017.01.23a', 'fixes.2017.01.23a', 'srcu.2017.01.25a' and 'torture.2017.01.15b' into HEAD

2017-01-25T20:56:05+00:00

doc.2017.01.15b: Documentation updates
dyntick.2017.01.23a: Dyntick tracking consolidation
fixes.2017.01.23a: Miscellaneous fixes
srcu.2017.01.25a: SRCU rewrite, fixes, and verification
torture.2017.01.15b: Torture-test updates