aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/admin-guide
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-16 16:28:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-16 16:28:19 -0700
commit94d18ee9340e00ee3455bb45661484093e3b2674 (patch)
tree6274a11e0b1201e0f1b7181649af922972d46f94 /Documentation/admin-guide
parentMerge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (diff)
parentMerge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu (diff)
downloadlinux-dev-94d18ee9340e00ee3455bb45661484093e3b2674.tar.xz
linux-dev-94d18ee9340e00ee3455bb45661484093e3b2674.zip
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar: "This cycle's RCU changes were: - A few more RCU flavor consolidation cleanups. - Updates to RCU's list-traversal macros improving lockdep usability. - Forward-progress improvements for no-CBs CPUs: Avoid ignoring incoming callbacks during grace-period waits. - Forward-progress improvements for no-CBs CPUs: Use ->cblist structure to take advantage of others' grace periods. - Also added a small commit that avoids needlessly inflicting scheduler-clock ticks on callback-offloaded CPUs. - Forward-progress improvements for no-CBs CPUs: Reduce contention on ->nocb_lock guarding ->cblist. - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass list to further reduce contention on ->nocb_lock guarding ->cblist. - Miscellaneous fixes. - Torture-test updates. - minor LKMM updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits) MAINTAINERS: Update from paulmck@linux.ibm.com to paulmck@kernel.org rcu: Don't include <linux/ktime.h> in rcutiny.h rcu: Allow rcu_do_batch() to dynamically adjust batch sizes rcu/nocb: Don't wake no-CBs GP kthread if timer posted under overload rcu/nocb: Reduce __call_rcu_nocb_wake() leaf rcu_node ->lock contention rcu/nocb: Reduce nocb_cb_wait() leaf rcu_node ->lock contention rcu/nocb: Advance CBs after merge in rcutree_migrate_callbacks() rcu/nocb: Avoid synchronous wakeup in __call_rcu_nocb_wake() rcu/nocb: Print no-CBs diagnostics when rcutorture writer unduly delayed rcu/nocb: EXP Check use and usefulness of ->nocb_lock_contended rcu/nocb: Add bypass callback queueing rcu/nocb: Atomic ->len field in rcu_segcblist structure rcu/nocb: Unconditionally advance and wake for excessive CBs rcu/nocb: Reduce ->nocb_lock contention with separate ->nocb_gp_lock rcu/nocb: Reduce contention at no-CBs invocation-done time rcu/nocb: Reduce contention at no-CBs registry-time CB advancement rcu/nocb: Round down for number of no-CBs grace-period kthreads rcu/nocb: Avoid ->nocb_lock capture by corresponding CPU rcu/nocb: Avoid needless wakeups of no-CBs grace-period kthread rcu/nocb: Make __call_rcu_nocb_wake() safe for many callbacks ...
Diffstat (limited to 'Documentation/admin-guide')
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt17
1 files changed, 11 insertions, 6 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 0d2a67e792ed..520dedae7150 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3842,12 +3842,13 @@
RCU_BOOST is not set, valid values are 0-99 and
the default is zero (non-realtime operation).
- rcutree.rcu_nocb_leader_stride= [KNL]
- Set the number of NOCB kthread groups, which
- defaults to the square root of the number of
- CPUs. Larger numbers reduces the wakeup overhead
- on the per-CPU grace-period kthreads, but increases
- that same overhead on each group's leader.
+ rcutree.rcu_nocb_gp_stride= [KNL]
+ Set the number of NOCB callback kthreads in
+ each group, which defaults to the square root
+ of the number of CPUs. Larger numbers reduce
+ the wakeup overhead on the global grace-period
+ kthread, but increases that same overhead on
+ each group's NOCB grace-period kthread.
rcutree.qhimark= [KNL]
Set threshold of queued RCU callbacks beyond which
@@ -4052,6 +4053,10 @@
rcutorture.verbose= [KNL]
Enable additional printk() statements.
+ rcupdate.rcu_cpu_stall_ftrace_dump= [KNL]
+ Dump ftrace buffer after reporting RCU CPU
+ stall warning.
+
rcupdate.rcu_cpu_stall_suppress= [KNL]
Suppress RCU CPU stall warning messages.