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author | Paul E. McKenney <paulmck@kernel.org> | 2023-03-22 03:28:40 +0300 |
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committer | Paul E. McKenney <paulmck@kernel.org> | 2023-05-10 03:24:20 +0300 |
commit | 51823ca651364f68bd3ad33d848c1542fffdd627 (patch) | |
tree | 871bee438bfb783e6cbbd882618d60d11eb97f81 /Documentation/admin-guide | |
parent | ac9a78681b921877518763ba0e89202254349d1b (diff) | |
download | linux-51823ca651364f68bd3ad33d848c1542fffdd627.tar.xz |
doc: Get rcutree module parameters back into alpha order
This commit puts the rcutree module parameters back into proper
alphabetical order.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'Documentation/admin-guide')
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 120 |
1 files changed, 60 insertions, 60 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e5bab29685f..8a094e2fc381 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -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(). |