On Mon, Oct 14, 2013 at 05:06:42PM +0800, chai wen wrote: > Hi Gleb > Thanks for you comment. > this new patch is based on git://git.kernel.org/pub/scm/virt/kvm/kvm.git > queue branch. > Page pinning is not mandatory in kvm async_pf processing and probably should > be dropped later.And we don't mind whether the GUP is failed or not.What we > need to do is to wake up guests process that is waitting on a page. > So drop the FOLL_GET flag in GUP, and do some simplifying in async_pf > check/clear processing. > thanks. > Have you tested it? Compiled it?
> Suggested-by: Gleb Natapov <[email protected]> > Signed-off-by: Gu zheng <[email protected]> > Signed-off-by: chai wen <[email protected]> > --- > arch/x86/kvm/x86.c | 4 ++-- > include/linux/kvm_host.h | 2 +- > virt/kvm/async_pf.c | 15 ++++----------- > 3 files changed, 7 insertions(+), 14 deletions(-) > > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index c951c71..edf2a07 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -7298,7 +7298,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, > struct kvm_async_pf *work) > int r; > > if ((vcpu->arch.mmu.direct_map != work->arch.direct_map) || > - is_error_page(work->page)) > + work->wakeup_all) > return; > > r = kvm_mmu_reload(vcpu); > @@ -7408,7 +7408,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, > struct x86_exception fault; > > trace_kvm_async_pf_ready(work->arch.token, work->gva); > - if (is_error_page(work->page)) > + if (work->wakeup_all) > work->arch.token = ~0; /* broadcast wakeup */ > else > kvm_del_async_pf_gfn(vcpu, work->arch.gfn); > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 7c961e1..5841e14 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -189,7 +189,7 @@ struct kvm_async_pf { > gva_t gva; > unsigned long addr; > struct kvm_arch_async_pf arch; > - struct page *page; > + bool wakeup_all; > }; > > void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu); > diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c > index b197950..81a98a4 100644 > --- a/virt/kvm/async_pf.c > +++ b/virt/kvm/async_pf.c > @@ -56,7 +56,6 @@ void kvm_async_pf_vcpu_init(struct kvm_vcpu *vcpu) > > static void async_pf_execute(struct work_struct *work) > { > - struct page *page = NULL; > struct kvm_async_pf *apf = > container_of(work, struct kvm_async_pf, work); > struct mm_struct *mm = apf->mm; > @@ -68,13 +67,12 @@ static void async_pf_execute(struct work_struct *work) > > use_mm(mm); > down_read(&mm->mmap_sem); > - get_user_pages(current, mm, addr, 1, 1, 0, &page, NULL); > + get_user_pages(current, mm, addr, 1, 1, 0, NULL, NULL); > up_read(&mm->mmap_sem); > unuse_mm(mm); > > spin_lock(&vcpu->async_pf.lock); > list_add_tail(&apf->link, &vcpu->async_pf.done); > - apf->page = page; > spin_unlock(&vcpu->async_pf.lock); > > /* > @@ -112,8 +110,6 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu > *vcpu) > list_entry(vcpu->async_pf.done.next, > typeof(*work), link); > list_del(&work->link); > - if (!is_error_page(work->page)) > - kvm_release_page_clean(work->page); > kmem_cache_free(async_pf_cache, work); > } > spin_unlock(&vcpu->async_pf.lock); > @@ -133,14 +129,11 @@ void kvm_check_async_pf_completion(struct kvm_vcpu > *vcpu) > list_del(&work->link); > spin_unlock(&vcpu->async_pf.lock); > > - if (work->page) > - kvm_arch_async_page_ready(vcpu, work); > + kvm_arch_async_page_ready(vcpu, work); > kvm_arch_async_page_present(vcpu, work); > > list_del(&work->queue); > vcpu->async_pf.queued--; > - if (!is_error_page(work->page)) > - kvm_release_page_clean(work->page); > kmem_cache_free(async_pf_cache, work); > } > } > @@ -163,7 +156,7 @@ int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, > gfn_t gfn, > if (!work) > return 0; > > - work->page = NULL; > + work->wakeup_all = false; > work->vcpu = vcpu; > work->gva = gva; > work->addr = gfn_to_hva(vcpu->kvm, gfn); > @@ -203,7 +196,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu) > if (!work) > return -ENOMEM; > > - work->page = KVM_ERR_PTR_BAD_PAGE; > + work->wakeup_all = true; > INIT_LIST_HEAD(&work->queue); /* for list_del to work */ > > spin_lock(&vcpu->async_pf.lock); > -- > 1.7.1 -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
