linux/arch
Nicholas Piggin 107c55005f powerpc/pseries: Add KVM guest doorbell restrictions
KVM guests have certain restrictions and performance quirks when using
doorbells. This patch moves the EPAPR KVM guest test so it can be shared
with PSERIES, and uses that in doorbell setup code to apply the KVM
guest quirks and  improves IPI performance for two cases:

 - PowerVM guests may now use doorbells even if they are secure.

 - KVM guests no longer use doorbells if XIVE is available.

There is a valid complaint that "KVM guest" is not a very reasonable
thing to test for, it's preferable for the hypervisor to advertise
particular behaviours to the guest so they could change if the
hypervisor implementation or configuration changes. However in this case
we were already assuming a KVM guest worst case, so this patch is about
containing those quirks. If KVM later advertises fast doorbells, we
should test for that and override the quirks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200726035155.1424103-4-npiggin@gmail.com
2020-07-29 21:02:10 +10:00
..
alpha Kbuild updates for v5.8 (2nd) 2020-06-13 13:29:16 -07:00
arc treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
arm maccess: make get_kernel_nofault() check for minimal type compatibility 2020-06-18 12:10:37 -07:00
arm64 Kbuild fixes for v5.8 2020-06-21 12:44:52 -07:00
c6x This time around we have 4 lines of diff in the core framework, removing a 2020-06-10 11:42:19 -07:00
csky maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
h8300 This time around we have 4 lines of diff in the core framework, removing a 2020-06-10 11:42:19 -07:00
hexagon treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
ia64 Merge branch 'hch' (maccess patches from Christoph Hellwig) 2020-06-18 12:35:51 -07:00
m68k macintosh/adb-iop: Implement SRQ autopolling 2020-07-26 23:34:24 +10:00
microblaze mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mips maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
nds32 maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
nios2 nios2 update for v5.8-rc1 2020-06-12 11:55:11 -07:00
openrisc OpenRISC updates for 5.8 2020-06-13 10:54:09 -07:00
parisc maccess: make get_kernel_nofault() check for minimal type compatibility 2020-06-18 12:10:37 -07:00
powerpc powerpc/pseries: Add KVM guest doorbell restrictions 2020-07-29 21:02:10 +10:00
riscv RISC-V Fixes for 5.8-rc2 2020-06-20 12:14:29 -07:00
s390 s390 fixes for 5.8-rc2 2020-06-20 12:31:08 -07:00
sh maccess: rename probe_kernel_address to get_kernel_nofault 2020-06-18 11:14:40 -07:00
sparc treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
um maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
unicore32 This time around we have 4 lines of diff in the core framework, removing a 2020-06-10 11:42:19 -07:00
x86 Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2020-06-20 19:18:27 -07:00
xtensa mmap locking API: convert mmap_sem API comments 2020-06-09 09:39:14 -07:00
.gitignore
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00