kernel/git/stable/linux.git/Documentation/RCU/stallwarn.txt, branch master

docs: RCU: Convert stallwarn.txt to ReST

2020-06-29T18:58:11+00:00

- Add a SPDX header; - Adjust document and section titles; - Fix list markups; - Some whitespace fixes and new line breaks; - Mark literal blocks as such; - Add it to RCU/index.rst. Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Paul E. McKenney

rcu: Remove kfree_rcu() special casing and lazy-callback handling

2020-01-24T18:24:31+00:00

This commit removes kfree_rcu() special-casing and the lazy-callback handling from Tree RCU. It moves some of this special casing to Tiny RCU, the removal of which will be the subject of later commits. This results in a nice negative delta. Suggested-by: Paul E. McKenney Signed-off-by: Joel Fernandes (Google) [ paulmck: Add slab.h #include, thanks to kbuild test robot . ] Signed-off-by: Paul E. McKenney

doc: Add rcutree.kthread_prio pointer to stallwarn.txt

2019-08-01T21:07:41+00:00

This commit adds mention of the rcutree.kthread_prio kernel boot parameter to the discussion of how high-priority real-time tasks can result in RCU CPU stall warnings. (However, this does not necessarily help when the high-priority real-time tasks are using dubious deadlines.) Signed-off-by: Paul E. McKenney

doc: Fixup definition of rcupdate.rcu_task_stall_timeout

2019-05-28T16:02:16+00:00

A positive value of rcupdate.rcu_task_stall_timeout is an interval in seconds rather than jiffies. Signed-off-by: Zhenzhong Duan Signed-off-by: Paul E. McKenney

rcu: Discard separate per-CPU callback counts

2019-01-25T23:28:30+00:00

Back when there were multiple flavors of RCU, it was necessary to separately count lazy and non-lazy callbacks for each CPU. These counts were used in CONFIG_RCU_FAST_NO_HZ kernels to determine how long a newly idle CPU should be allowed to sleep before handling its RCU callbacks. But now that there is only one flavor, the callback counts for a given CPU's sole rcu_data structure are the counts for that CPU. This commit therefore removes the rcu_data structure's ->nonlazy_posted and ->nonlazy_posted_snap fields, the rcu_idle_count_callbacks_posted() and rcu_cpu_has_callbacks() functions, repurposes the rcu_data structure's ->all_lazy field to record the laziness state at the beginning of the latest idle sojourn, and modifies CONFIG_RCU_FAST_NO_HZ RCU CPU stall warnings accordingly. Signed-off-by: Paul E. McKenney

doc: Correct parameter in stallwarn

2018-11-12T16:56:25+00:00

The stallwarn document incorrectly mentions 'fps=' instead of 'fqs='. This commit orrects that. Signed-off-by: Joel Fernandes (Google) Signed-off-by: Paul E. McKenney

doc: Remove rcu_preempt_state reference in stallwarn

2018-11-09T05:44:41+00:00

Consolidation of RCU-bh, RCU-preempt, and RCU-sched into one RCU flavor to rule them all resulted in the removal of rcu_preempt_state. However, stallwarn.txt still mentions rcu_preempt_state. This commit therefore Updates stallwarn documentation accordingly. Signed-off-by: Joel Fernandes (Google) Cc: Signed-off-by: Paul E. McKenney

doc: Update removal of RCU-bh/sched update machinery

2018-08-30T17:59:48+00:00

The RCU-bh update API is now defined in terms of that of RCU-bh and RCU-sched, so this commit updates the documentation accordingly. In addition, although RCU-sched persists in !PREEMPT kernels, in the PREEMPT case its update API is now defined in terms of that of RCU-preempt, so this commit also updates the documentation accordingly. While in the area, this commit removes the documentation for the now-obsolete synchronize_rcu_mult() and clarifies the Tasks RCU documentation. Signed-off-by: Paul E. McKenney

doc: Update RCU CPU stall-warning documentation

2018-07-12T22:38:51+00:00

Signed-off-by: Paul E. McKenney

doc: Eliminate cond_resched_rcu_qs() in favor of cond_resched()

2017-12-04T18:28:59+00:00

Now that cond_resched() also provides RCU quiescent states when needed, it can be used in place of cond_resched_rcu_qs(). This commit therefore documents this change. Signed-off-by: Paul E. McKenney