The current number of KVM_IRQCHIP_NUM_PINS results in an order 3

allocation (32kb) for each guest start/restart which can result in OOM
 killer activity when kernel memory is fragmented enough.
 
 This fix reduces the number of iopins as s390 doesn't use them, hence
 reducing the memory footprint.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEwGNS88vfc9+v45Yq41TmuOI4ufgFAl7xxoUACgkQ41TmuOI4
 ufg5Lg//QFzh7hEchnMBJeA+RSXnZtzsOzhOn0QYrKQM9a++CLJJU0FL+6gXL8vv
 BPBK5E44K8sv0imDCXYgocZoxn4xcAvdwXbfp9lncaiYse54hY31y3YLbCULPTHy
 DDA6vuetoEeLO1djVtu0Ot0gkAjAPPnEdbhkaN7i378oe2HlXD9ALd53uhCAL0J3
 KyKvrlbOoOz60uLF5E+INZ01GxXHxhpb55UKR+9YhtukOC6TPyfl+T7ifneBh8fl
 U1ZtAAOa6kxl6amDdWBnnbmV0SxQDlWMouueqZvN1Wy0E59eX20v6zKmn+nXkSYZ
 IJfX/QZw0swOnmt4vj+6y84zw52VtA43hNCdXsHd4I63uWV1SIufwDZDLlWHePPF
 nWNZ7zQhV7Qt4K/fCWW2zCS1Jf8FNlgeXpouZaKdUsYoA5XKm6CZqb4nwkOGI/pk
 G++E/gsomk+lvsAmyEi/Wj7nCPl4kJdsOUn6QRu5jDPNgydkkTMccHWqTHEg7Fjt
 tGPiGOpH19pHg24gP5QBjJtyfFmGhV2i8f6h5h3m9JWyTmNm8389DU9OBFigbOGf
 lyxODwgnCiCp+TDIiHvsJeG2Lz7z8kAisewDyMOrqpttmkEhi/4QhXhdWlcIqh3h
 9KJ08A7lj3FOw4z5PV0zfeETms99kCxjCXTKL+79yS7F2w6xADY=
 =s85F
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-master-5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-master

The current number of KVM_IRQCHIP_NUM_PINS results in an order 3
allocation (32kb) for each guest start/restart which can result in OOM
killer activity when kernel memory is fragmented enough.

This fix reduces the number of iopins as s390 doesn't use them, hence
reducing the memory footprint.
This commit is contained in:
Paolo Bonzini 2020-06-24 02:44:27 -04:00
commit 0a1ef9c81e

View File

@ -31,12 +31,12 @@
#define KVM_USER_MEM_SLOTS 32
/*
* These seem to be used for allocating ->chip in the routing table,
* which we don't use. 4096 is an out-of-thin-air value. If we need
* to look at ->chip later on, we'll need to revisit this.
* These seem to be used for allocating ->chip in the routing table, which we
* don't use. 1 is as small as we can get to reduce the needed memory. If we
* need to look at ->chip later on, we'll need to revisit this.
*/
#define KVM_NR_IRQCHIPS 1
#define KVM_IRQCHIP_NUM_PINS 4096
#define KVM_IRQCHIP_NUM_PINS 1
#define KVM_HALT_POLL_NS_DEFAULT 50000
/* s390-specific vcpu->requests bit members */