> On Sep 15, 2020, at 3:24 PM, Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > > Hi, > > Entries in the kernel-parameters.txt file should be kept in alphabetical order > mostly (there are a few exceptions where related options are kept together). > > > > On 9/15/20 11:05 AM, Alex Kogan wrote: >> Keep track of the time the thread at the head of the secondary queue >> has been waiting, and force inter-node handoff once this time passes >> a preset threshold. The default value for the threshold (10ms) can be >> overridden with the new kernel boot command-line option >> "numa_spinlock_threshold". The ms value is translated internally to the >> nearest rounded-up jiffies. >> >> Signed-off-by: Alex Kogan <alex.kogan@xxxxxxxxxx> >> Reviewed-by: Steve Sistare <steven.sistare@xxxxxxxxxx> >> Reviewed-by: Waiman Long <longman@xxxxxxxxxx> >> --- >> .../admin-guide/kernel-parameters.txt | 9 ++ >> kernel/locking/qspinlock_cna.h | 95 ++++++++++++++++--- >> 2 files changed, 92 insertions(+), 12 deletions(-) >> >> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt >> index 51ce050f8701..73ab23a47b97 100644 >> --- a/Documentation/admin-guide/kernel-parameters.txt >> +++ b/Documentation/admin-guide/kernel-parameters.txt >> @@ -3363,6 +3363,15 @@ >> Not specifying this option is equivalent to >> numa_spinlock=auto. >> >> + numa_spinlock_threshold= [NUMA, PV_OPS] >> + Set the time threshold in milliseconds for the >> + number of intra-node lock hand-offs before the >> + NUMA-aware spinlock is forced to be passed to >> + a thread on another NUMA node. Valid values >> + are in the [1..100] range. Smaller values result >> + in a more fair, but less performant spinlock, >> + and vice versa. The default value is 10. >> + >> cpu0_hotplug [X86] Turn on CPU0 hotplug feature when >> CONFIG_BOOTPARAM_HOTPLUG_CPU0 is off. >> Some features depend on CPU0. Known dependencies are: > > > This new entry and numa_spinlock from patch 3/5 should go between these other 2 NUMA entries: > > numa_balancing= [KNL,X86] Enable or disable automatic NUMA balancing. > Allowed values are enable and disable > > numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA. > 'node', 'default' can be specified > This can be set from sysctl after boot. > See Documentation/admin-guide/sysctl/vm.rst for details. Will fix that, thanks. > > > Oooh, that cpu0_hotplug entry is way out of place. I'll send a patch for that. Sounds good. — Alex
