Improve make_secure_pte to avoid stalls when the system is heavily overcommitted. This was especially problematic in kvm_s390_pv_unpack, because of the loop over all pages that needed unpacking. Also fix kvm_s390_pv_init_vm to avoid stalls when the system is heavily overcommitted. Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> --- arch/s390/kernel/uv.c | 11 ++++++++--- arch/s390/kvm/pv.c | 2 +- 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c index aeb0a15bcbb7..fd0faa51c1bb 100644 --- a/arch/s390/kernel/uv.c +++ b/arch/s390/kernel/uv.c @@ -196,11 +196,16 @@ static int make_secure_pte(pte_t *ptep, unsigned long addr, if (!page_ref_freeze(page, expected)) return -EBUSY; set_bit(PG_arch_1, &page->flags); - rc = uv_call(0, (u64)uvcb); + rc = __uv_call(0, (u64)uvcb); page_ref_unfreeze(page, expected); - /* Return -ENXIO if the page was not mapped, -EINVAL otherwise */ - if (rc) + /* + * Return -ENXIO if the page was not mapped, -EINVAL for other errors. + * If busy or partially completed, return -EAGAIN. + */ + if (rc == 1) rc = uvcb->rc == 0x10a ? -ENXIO : -EINVAL; + else if (rc > 1) + rc = -EAGAIN; return rc; } diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c index c8841f476e91..e007df11a2fe 100644 --- a/arch/s390/kvm/pv.c +++ b/arch/s390/kvm/pv.c @@ -196,7 +196,7 @@ int kvm_s390_pv_init_vm(struct kvm *kvm, u16 *rc, u16 *rrc) uvcb.conf_base_stor_origin = (u64)kvm->arch.pv.stor_base; uvcb.conf_virt_stor_origin = (u64)kvm->arch.pv.stor_var; - cc = uv_call(0, (u64)&uvcb); + cc = uv_call_sched(0, (u64)&uvcb); *rc = uvcb.header.rc; *rrc = uvcb.header.rrc; KVM_UV_EVENT(kvm, 3, "PROTVIRT CREATE VM: handle %llx len %llx rc %x rrc %x", -- 2.31.1
