diff options
| author | Suresh E. Warrier <warrier@linux.vnet.ibm.com> | 2015-12-21 23:33:57 +0100 |
|---|---|---|
| committer | Paul Mackerras <paulus@samba.org> | 2016-02-29 06:25:06 +0100 |
| commit | 520fe9c607d3acea96391aad27e17518bd7d39bd (patch) | |
| tree | ee3c420760c8d739bfe2cfa9d928c40622545c69 /arch/powerpc/kvm/book3s_hv.c | |
| parent | KVM: PPC: Book3S HV: Send IPI to host core to wake VCPU (diff) | |
| download | linux-520fe9c607d3acea96391aad27e17518bd7d39bd.tar.xz linux-520fe9c607d3acea96391aad27e17518bd7d39bd.zip | |
KVM: PPC: Book3S HV: Add tunable to control H_IPI redirection
Redirecting the wakeup of a VCPU from the H_IPI hypercall to
a core running in the host is usually a good idea, most workloads
seemed to benefit. However, in one heavily interrupt-driven SMT1
workload, some regression was observed. This patch adds a kvm_hv
module parameter called h_ipi_redirect to control this feature.
The default value for this tunable is 1 - that is enable the feature.
Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index c3c731085c1f..f47fffefadc1 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -81,6 +81,17 @@ static int target_smt_mode; module_param(target_smt_mode, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(target_smt_mode, "Target threads per core (0 = max)"); +#ifdef CONFIG_KVM_XICS +static struct kernel_param_ops module_param_ops = { + .set = param_set_int, + .get = param_get_int, +}; + +module_param_cb(h_ipi_redirect, &module_param_ops, &h_ipi_redirect, + S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(h_ipi_redirect, "Redirect H_IPI wakeup to a free host core"); +#endif + static void kvmppc_end_cede(struct kvm_vcpu *vcpu); static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu); |