Commit 51823ca6 authored by Paul E. McKenney's avatar Paul E. McKenney
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doc: Get rcutree module parameters back into alpha order



This commit puts the rcutree module parameters back into proper
alphabetical order.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent ac9a7868
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+60 −60
Original line number Diff line number Diff line
@@ -4736,43 +4736,6 @@
			the propagation of recent CPU-hotplug changes up
			the rcu_node combining tree.

	rcutree.use_softirq=	[KNL]
			If set to zero, move all RCU_SOFTIRQ processing to
			per-CPU rcuc kthreads.  Defaults to a non-zero
			value, meaning that RCU_SOFTIRQ is used by default.
			Specify rcutree.use_softirq=0 to use rcuc kthreads.

			But note that CONFIG_PREEMPT_RT=y kernels disable
			this kernel boot parameter, forcibly setting it
			to zero.

	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]
			Change the number of CPUs assigned to each
			leaf rcu_node structure.  Useful for very
			large systems, which will choose the value 64,
			and for NUMA systems with large remote-access
			latencies, which will choose a value aligned
			with the appropriate hardware boundaries.

	rcutree.rcu_min_cached_objs= [KNL]
			Minimum number of objects which are cached and
			maintained per one CPU. Object size is equal
			to PAGE_SIZE. The cache allows to reduce the
			pressure to page allocator, also it makes the
			whole algorithm to behave better in low memory
			condition.

	rcutree.rcu_delay_page_cache_fill_msec= [KNL]
			Set the page-cache refill delay (in milliseconds)
			in response to low-memory conditions.  The range
			of permitted values is in the range 0:100000.

	rcutree.jiffies_till_first_fqs= [KNL]
			Set delay from grace-period initialization to
			first attempt to force quiescent states.
@@ -4811,21 +4774,6 @@
			When RCU_NOCB_CPU is set, also adjust the
			priority of NOCB callback kthreads.

	rcutree.rcu_divisor= [KNL]
			Set the shift-right count to use to compute
			the callback-invocation batch limit bl from
			the number of callbacks queued on this CPU.
			The result will be bounded below by the value of
			the rcutree.blimit kernel parameter.  Every bl
			callbacks, the softirq handler will exit in
			order to allow the CPU to do other work.

			Please note that this callback-invocation batch
			limit applies only to non-offloaded callback
			invocation.  Offloaded callbacks are instead
			invoked in the context of an rcuoc kthread, which
			scheduler will preempt as it does any other task.

	rcutree.nocb_nobypass_lim_per_jiffy= [KNL]
			On callback-offloaded (rcu_nocbs) CPUs,
			RCU reduces the lock contention that would
@@ -4839,14 +4787,6 @@
			the ->nocb_bypass queue.  The definition of "too
			many" is supplied by this kernel boot parameter.

	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
			batch limiting is disabled.
@@ -4864,6 +4804,56 @@
			on rcutree.qhimark at boot time and to zero to
			disable more aggressive help enlistment.

	rcutree.rcu_delay_page_cache_fill_msec= [KNL]
			Set the page-cache refill delay (in milliseconds)
			in response to low-memory conditions.  The range
			of permitted values is in the range 0:100000.

	rcutree.rcu_divisor= [KNL]
			Set the shift-right count to use to compute
			the callback-invocation batch limit bl from
			the number of callbacks queued on this CPU.
			The result will be bounded below by the value of
			the rcutree.blimit kernel parameter.  Every bl
			callbacks, the softirq handler will exit in
			order to allow the CPU to do other work.

			Please note that this callback-invocation batch
			limit applies only to non-offloaded callback
			invocation.  Offloaded callbacks are instead
			invoked in the context of an rcuoc kthread, which
			scheduler will preempt as it does any other task.

	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]
			Change the number of CPUs assigned to each
			leaf rcu_node structure.  Useful for very
			large systems, which will choose the value 64,
			and for NUMA systems with large remote-access
			latencies, which will choose a value aligned
			with the appropriate hardware boundaries.

	rcutree.rcu_min_cached_objs= [KNL]
			Minimum number of objects which are cached and
			maintained per one CPU. Object size is equal
			to PAGE_SIZE. The cache allows to reduce the
			pressure to page allocator, also it makes the
			whole algorithm to behave better in low memory
			condition.

	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.rcu_kick_kthreads= [KNL]
			Cause the grace-period kthread to get an extra
			wake_up() if it sleeps three times longer than
@@ -4885,6 +4875,16 @@
			rcu_node tree with an eye towards determining
			why a new grace period has not yet started.

	rcutree.use_softirq=	[KNL]
			If set to zero, move all RCU_SOFTIRQ processing to
			per-CPU rcuc kthreads.  Defaults to a non-zero
			value, meaning that RCU_SOFTIRQ is used by default.
			Specify rcutree.use_softirq=0 to use rcuc kthreads.

			But note that CONFIG_PREEMPT_RT=y kernels disable
			this kernel boot parameter, forcibly setting it
			to zero.

	rcuscale.gp_async= [KNL]
			Measure performance of asynchronous
			grace-period primitives such as call_rcu().