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| author | Michael Ellerman <mpe@ellerman.id.au> | 2014-05-23 12:15:29 +0400 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2014-05-28 07:35:37 +0400 |
| commit | 3102f7843c75014fa15d3e6fda3b49f61bc467b4 (patch) | |
| tree | 16ab9545e46162b3c6735d13be0b8a04292b7098 /arch/powerpc/kvm/powerpc.c | |
| parent | 6f5e40a3001d2497a134386a173e3ec3fdf2ad0b (diff) | |
| download | linux-3102f7843c75014fa15d3e6fda3b49f61bc467b4.tar.xz | |
powerpc/kvm/book3s_hv: Use threads_per_subcore in KVM
To support split core on POWER8 we need to modify various parts of the
KVM code to use threads_per_subcore instead of threads_per_core. On
systems that do not support split core threads_per_subcore ==
threads_per_core and these changes are a nop.
We use threads_per_subcore as the value reported by KVM_CAP_PPC_SMT.
This communicates to userspace that guests can only be created with
a value of threads_per_core that is less than or equal to the current
threads_per_subcore. This ensures that guests can only be created with a
thread configuration that we are able to run given the current split
core mode.
Although threads_per_subcore can change during the life of the system,
the commit that enables that will ensure that threads_per_subcore does
not change during the life of a KVM VM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Alexander Graf <agraf@suse.de>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kvm/powerpc.c')
| -rw-r--r-- | arch/powerpc/kvm/powerpc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 3cf541a53e2a..27919a8715cf 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -384,7 +384,7 @@ int kvm_dev_ioctl_check_extension(long ext) #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE case KVM_CAP_PPC_SMT: if (hv_enabled) - r = threads_per_core; + r = threads_per_subcore; else r = 0; break; |