linux-stable.git/kernel/rcu/tree.h, branch v5.0

rcutorture: Print time since GP end upon forward-progress failure

2018-12-01T20:45:40+00:00

If rcutorture's forward-progress tests fail while a grace period is not
in progress, it is useful to print the time since the last grace period
ended as a way to detect failure to launch a new grace period.  This
commit therefore makes this change.

Signed-off-by: Paul E. McKenney

rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings

2018-12-01T20:45:37+00:00

The RCU CPU stall warnings print an estimate of the total number of
RCU callbacks queued in the system, but this estimate leaves out
the callbacks queued for nocbs CPUs.  This commit therefore introduces
rcu_get_n_cbs_cpu(), which gives an accurate callback estimate for
both nocbs and normal CPUs, and uses this new function as needed.

This commit also introduces a rcu_get_n_cbs_nocb_cpu() helper function
that returns the number of callbacks for nocbs CPUs or zero otherwise,
and also uses this function in place of direct access to ->nocb_q_count
while in the area (fewer characters, you see).

Signed-off-by: Paul E. McKenney

rcu: Fix rcu_{node,data} comments about gp_seq_needed

2018-11-09T05:43:20+00:00

Recent changes have removed the old ->gp_seq_needed field from the
rcu_state structure, which in turn obsoleted a couple of comments in
the rcu_node and rcu_data structures.  This commit therefore updates
these comments accordingly.

Signed-off-by: Joel Fernandes (Google) 
Cc: 
Signed-off-by: Paul E. McKenney

rcu: Remove unused rcu_state externs

2018-11-09T05:43:20+00:00

The rcu_bh_state and rcu_sched_state variables were removed during the
RCU flavor consolidations, but external declarations remain in tree.h.
This commit therefore removes these obsolete declarations.

Signed-off-by: Joel Fernandes (Google) 
Cc: 
Signed-off-by: Paul E. McKenney

rcu: Convert rcu_state.ofl_lock to raw_spinlock_t

2018-08-30T23:03:54+00:00

1e64b15a4b10 ("rcu: Fix grace-period hangs due to race with CPU offline")
added spinlock_t ofl_lock to the rcu_state structure, then takes it with
preemption disabled during CPU offline, which gives the -rt patchset's
sleeping spinlock heartburn.

This commit therefore converts ->ofl_lock to raw_spinlock_t.

Signed-off-by: Mike Galbraith 
Signed-off-by: Paul E. McKenney 
Cc: Sebastian Andrzej Siewior

rcu: Remove obsolete ->dynticks_fqs and ->cond_resched_completed

2018-08-30T23:03:53+00:00

The rcu_data structure's ->dynticks_fqs is incremented but never
accesses.  Its ->cond_resched_completed field isn't used at all.
This commit therefore removes both fields.

Signed-off-by: Paul E. McKenney

rcu: Switch ->dynticks to rcu_data structure, remove rcu_dynticks

2018-08-30T23:03:52+00:00

This commit move ->dynticks from the rcu_dynticks structure to the
rcu_data structure, replacing the field of the same name.  It also updates
the code to access ->dynticks from the rcu_data structure and to use the
rcu_data structure rather than following to now-gone ->dynticks field
to the now-gone rcu_dynticks structure.  While in the area, this commit
also fixes up comments.

Signed-off-by: Paul E. McKenney

rcu: Switch dyntick nesting counters to rcu_data structure

2018-08-30T23:03:51+00:00

This commit removes ->dynticks_nesting and ->dynticks_nmi_nesting from
the rcu_dynticks structure and updates the code to access them from the
rcu_data structure.

Signed-off-by: Paul E. McKenney

rcu: Switch urgent quiescent-state requests to rcu_data structure

2018-08-30T23:03:50+00:00

This commit removes ->rcu_need_heavy_qs and ->rcu_urgent_qs from the
rcu_dynticks structure and updates the code to access them from the
rcu_data structure.

Signed-off-by: Paul E. McKenney

rcu: Switch lazy counts to rcu_data structure

2018-08-30T23:03:49+00:00

This commit removes ->all_lazy, ->nonlazy_posted and ->nonlazy_posted_snap
from the rcu_dynticks structure and updates the code to access them from
the rcu_data structure.

Signed-off-by: Paul E. McKenney