mm/vmscan.c: remove cpu online notification for now
authorWei Yang <richardw.yang@linux.intel.com>
Thu, 2 Apr 2020 04:10:09 +0000 (21:10 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 2 Apr 2020 16:35:31 +0000 (09:35 -0700)
commit6b700b5b3c595594c7c0c608cfe903c4e3a0af2d
treebedec11321b9c3a8da95562cc40b1dd56fd28a04
parentf661d007f40dffc719c1b2b1a636b759f87c4e78
mm/vmscan.c: remove cpu online notification for now

kswapd kernel thread starts either with a CPU affinity set to the full cpu
mask of its target node or without any affinity at all if the node is
CPUless.  There is a cpu hotplug callback (kswapd_cpu_online) that
implements an elaborate way to update this mask when a cpu is onlined.

It is not really clear whether there is any actual benefit from this
scheme. Completely CPU-less NUMA nodes rarely gain a new CPU during
runtime. Drop the code for that reason. If there is a real usecase then
we can resurrect and simplify the code.

[mhocko@suse.com rewrite changelog]

Suggested-by: Michal Hocko <mhocko@suse.org>
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/20200218224422.3407-1-richardw.yang@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/vmscan.c