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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 00:01:01 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-23 00:01:01 +0300
commitfc934d40178ad4e551a17e2733241d9f29fddd70 (patch)
tree43e3f3c9019915cc41befec4dad5d1328a4cae63 /Documentation/kernel-parameters.txt
parent052b398a43a7de8c68c13e7fa05d6b3d16ce6801 (diff)
parent085c789783f5f95c253740d3d0a1659ec5ff32a8 (diff)
downloadlinux-fc934d40178ad4e551a17e2733241d9f29fddd70.tar.xz
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar: - Continued initialization/Kconfig updates: hide most Kconfig options from unsuspecting users. There's now a single high level configuration option: * * RCU Subsystem * Make expert-level adjustments to RCU configuration (RCU_EXPERT) [N/y/?] (NEW) Which if answered in the negative, leaves us with a single interactive configuration option: Offload RCU callback processing from boot-selected CPUs (RCU_NOCB_CPU) [N/y/?] (NEW) All the rest of the RCU options are configured automatically. Later on we'll remove this single leftover configuration option as well. - Remove all uses of RCU-protected array indexes: replace the rcu_[access|dereference]_index_check() APIs with READ_ONCE() and rcu_lockdep_assert() - RCU CPU-hotplug cleanups - Updates to Tiny RCU: a race fix and further code shrinkage. - RCU torture-testing updates: fixes, speedups, cleanups and documentation updates. - Miscellaneous fixes - Documentation updates * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) rcutorture: Allow repetition factors in Kconfig-fragment lists rcutorture: Display "make oldconfig" errors rcutorture: Update TREE_RCU-kconfig.txt rcutorture: Make rcutorture scripts force RCU_EXPERT rcutorture: Update configuration fragments for rcutree.rcu_fanout_exact rcutorture: TASKS_RCU set directly, so don't explicitly set it rcutorture: Test SRCU cleanup code path rcutorture: Replace barriers with smp_store_release() and smp_load_acquire() locktorture: Change longdelay_us to longdelay_ms rcutorture: Allow negative values of nreaders to oversubscribe rcutorture: Exchange TREE03 and TREE08 NR_CPUS, speed up CPU hotplug rcutorture: Exchange TREE03 and TREE04 geometries locktorture: fix deadlock in 'rw_lock_irq' type rcu: Correctly handle non-empty Tiny RCU callback list with none ready rcutorture: Test both RCU-sched and RCU-bh for Tiny RCU rcu: Further shrink Tiny RCU by making empty functions static inlines rcu: Conditionally compile RCU's eqs warnings rcu: Remove prompt for RCU implementation rcu: Make RCU able to tolerate undefined CONFIG_RCU_KTHREAD_PRIO rcu: Make RCU able to tolerate undefined CONFIG_RCU_FANOUT_LEAF ...
Diffstat (limited to 'Documentation/kernel-parameters.txt')
-rw-r--r--Documentation/kernel-parameters.txt33
1 files changed, 30 insertions, 3 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 6726139bd289..60c9d6d0fd96 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2998,11 +2998,34 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Set maximum number of finished RCU callbacks to
process in one batch.
+ rcutree.dump_tree= [KNL]
+ Dump the structure of the rcu_node combining tree
+ out at early boot. This is used for diagnostic
+ purposes, to verify correct tree setup.
+
+ rcutree.gp_cleanup_delay= [KNL]
+ Set the number of jiffies to delay each step of
+ RCU grace-period cleanup. This only has effect
+ when CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP is set.
+
rcutree.gp_init_delay= [KNL]
Set the number of jiffies to delay each step of
RCU grace-period initialization. This only has
- effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT is
- set.
+ effect when CONFIG_RCU_TORTURE_TEST_SLOW_INIT
+ is set.
+
+ rcutree.gp_preinit_delay= [KNL]
+ Set the number of jiffies to delay each step of
+ RCU grace-period pre-initialization, that is,
+ the propagation of recent CPU-hotplug changes up
+ the rcu_node combining tree. This only has effect
+ when CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT is set.
+
+ rcutree.rcu_fanout_exact= [KNL]
+ Disable autobalancing of the rcu_node combining
+ tree. This is used by rcutorture, and might
+ possibly be useful for architectures having high
+ cache-to-cache transfer latencies.
rcutree.rcu_fanout_leaf= [KNL]
Increase the number of CPUs assigned to each
@@ -3107,7 +3130,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
test, hence the "fake".
rcutorture.nreaders= [KNL]
- Set number of RCU readers.
+ Set number of RCU readers. The value -1 selects
+ N-1, where N is the number of CPUs. A value
+ "n" less than -1 selects N-n-2, where N is again
+ the number of CPUs. For example, -2 selects N
+ (the number of CPUs), -3 selects N+1, and so on.
rcutorture.object_debug= [KNL]
Enable debug-object double-call_rcu() testing.