diff options
author | David S. Miller <davem@davemloft.net> | 2018-01-17 00:00:25 -0500 |
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committer | David S. Miller <davem@davemloft.net> | 2018-01-17 00:10:42 -0500 |
commit | c02b3741eb99a1ec733e6134c53ba59e43e19e97 (patch) | |
tree | ff7dd96c32dec2abe530e7101378443dabcb8962 /arch/powerpc/kvm/book3s_64_mmu_hv.c | |
parent | 7018d1b3f20fb4308ed9bc577160cb8ffb79b62a (diff) | |
parent | 8cbab92dff778e516064c13113ca15d4869ec883 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes all over.
The mini-qdisc bits were a little bit tricky, however.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_hv.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_hv.c | 90 |
1 files changed, 61 insertions, 29 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 966097232d21..b73dbc9e797d 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -65,11 +65,17 @@ struct kvm_resize_hpt { u32 order; /* These fields protected by kvm->lock */ + + /* Possible values and their usage: + * <0 an error occurred during allocation, + * -EBUSY allocation is in the progress, + * 0 allocation made successfuly. + */ int error; - bool prepare_done; - /* Private to the work thread, until prepare_done is true, - * then protected by kvm->resize_hpt_sem */ + /* Private to the work thread, until error != -EBUSY, + * then protected by kvm->lock. + */ struct kvm_hpt_info hpt; }; @@ -159,8 +165,6 @@ long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order) * Reset all the reverse-mapping chains for all memslots */ kvmppc_rmap_reset(kvm); - /* Ensure that each vcpu will flush its TLB on next entry. */ - cpumask_setall(&kvm->arch.need_tlb_flush); err = 0; goto out; } @@ -176,6 +180,10 @@ long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order) kvmppc_set_hpt(kvm, &info); out: + if (err == 0) + /* Ensure that each vcpu will flush its TLB on next entry. */ + cpumask_setall(&kvm->arch.need_tlb_flush); + mutex_unlock(&kvm->lock); return err; } @@ -1413,16 +1421,20 @@ static void resize_hpt_pivot(struct kvm_resize_hpt *resize) static void resize_hpt_release(struct kvm *kvm, struct kvm_resize_hpt *resize) { - BUG_ON(kvm->arch.resize_hpt != resize); + if (WARN_ON(!mutex_is_locked(&kvm->lock))) + return; if (!resize) return; - if (resize->hpt.virt) - kvmppc_free_hpt(&resize->hpt); + if (resize->error != -EBUSY) { + if (resize->hpt.virt) + kvmppc_free_hpt(&resize->hpt); + kfree(resize); + } - kvm->arch.resize_hpt = NULL; - kfree(resize); + if (kvm->arch.resize_hpt == resize) + kvm->arch.resize_hpt = NULL; } static void resize_hpt_prepare_work(struct work_struct *work) @@ -1431,17 +1443,41 @@ static void resize_hpt_prepare_work(struct work_struct *work) struct kvm_resize_hpt, work); struct kvm *kvm = resize->kvm; - int err; + int err = 0; - resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n", - resize->order); - - err = resize_hpt_allocate(resize); + if (WARN_ON(resize->error != -EBUSY)) + return; mutex_lock(&kvm->lock); + /* Request is still current? */ + if (kvm->arch.resize_hpt == resize) { + /* We may request large allocations here: + * do not sleep with kvm->lock held for a while. + */ + mutex_unlock(&kvm->lock); + + resize_hpt_debug(resize, "resize_hpt_prepare_work(): order = %d\n", + resize->order); + + err = resize_hpt_allocate(resize); + + /* We have strict assumption about -EBUSY + * when preparing for HPT resize. + */ + if (WARN_ON(err == -EBUSY)) + err = -EINPROGRESS; + + mutex_lock(&kvm->lock); + /* It is possible that kvm->arch.resize_hpt != resize + * after we grab kvm->lock again. + */ + } + resize->error = err; - resize->prepare_done = true; + + if (kvm->arch.resize_hpt != resize) + resize_hpt_release(kvm, resize); mutex_unlock(&kvm->lock); } @@ -1466,14 +1502,12 @@ long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm, if (resize) { if (resize->order == shift) { - /* Suitable resize in progress */ - if (resize->prepare_done) { - ret = resize->error; - if (ret != 0) - resize_hpt_release(kvm, resize); - } else { + /* Suitable resize in progress? */ + ret = resize->error; + if (ret == -EBUSY) ret = 100; /* estimated time in ms */ - } + else if (ret) + resize_hpt_release(kvm, resize); goto out; } @@ -1493,6 +1527,8 @@ long kvm_vm_ioctl_resize_hpt_prepare(struct kvm *kvm, ret = -ENOMEM; goto out; } + + resize->error = -EBUSY; resize->order = shift; resize->kvm = kvm; INIT_WORK(&resize->work, resize_hpt_prepare_work); @@ -1547,16 +1583,12 @@ long kvm_vm_ioctl_resize_hpt_commit(struct kvm *kvm, if (!resize || (resize->order != shift)) goto out; - ret = -EBUSY; - if (!resize->prepare_done) - goto out; - ret = resize->error; - if (ret != 0) + if (ret) goto out; ret = resize_hpt_rehash(resize); - if (ret != 0) + if (ret) goto out; resize_hpt_pivot(resize); |