| Message ID | 20211119235759.1304274-12-dmatlack@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86/mmu: Eager Page Splitting for the TDP MMU | expand |
On Fri, Nov 19, 2021 at 3:58 PM David Matlack <dmatlack@google.com> wrote: > > Instead of passing a pointer to the root page table and the root level > seperately, pass in a pointer to the kvm_mmu_page that backs the root. > This reduces the number of arguments by 1, cutting down on line lengths. > > No functional change intended. > > Signed-off-by: David Matlack <dmatlack@google.com> Reviewed-by: Ben Gardon <bgardon@google.com> > --- > arch/x86/kvm/mmu/tdp_iter.c | 5 ++++- > arch/x86/kvm/mmu/tdp_iter.h | 10 +++++----- > arch/x86/kvm/mmu/tdp_mmu.c | 14 +++++--------- > 3 files changed, 14 insertions(+), 15 deletions(-) > > diff --git a/arch/x86/kvm/mmu/tdp_iter.c b/arch/x86/kvm/mmu/tdp_iter.c > index b3ed302c1a35..92b3a075525a 100644 > --- a/arch/x86/kvm/mmu/tdp_iter.c > +++ b/arch/x86/kvm/mmu/tdp_iter.c > @@ -39,9 +39,12 @@ void tdp_iter_restart(struct tdp_iter *iter) > * Sets a TDP iterator to walk a pre-order traversal of the paging structure > * rooted at root_pt, starting with the walk to translate next_last_level_gfn. > */ > -void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, > +void tdp_iter_start(struct tdp_iter *iter, struct kvm_mmu_page *root, I think this is an artifact of the days when I thought we could avoid allocating struct kvm_mmu_pages for the TDP MMU. Trying to do that turned out to be a huge pain though and the memory savings weren't great. Happy to see this cleaned up. > int min_level, gfn_t next_last_level_gfn) > { > + u64 *root_pt = root->spt; > + int root_level = root->role.level; > + > WARN_ON(root_level < 1); > WARN_ON(root_level > PT64_ROOT_MAX_LEVEL); > > diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h > index b1748b988d3a..ec1f58013428 100644 > --- a/arch/x86/kvm/mmu/tdp_iter.h > +++ b/arch/x86/kvm/mmu/tdp_iter.h > @@ -51,17 +51,17 @@ struct tdp_iter { > * Iterates over every SPTE mapping the GFN range [start, end) in a > * preorder traversal. > */ > -#define for_each_tdp_pte_min_level(iter, root, root_level, min_level, start, end) \ > - for (tdp_iter_start(&iter, root, root_level, min_level, start); \ > +#define for_each_tdp_pte_min_level(iter, root, min_level, start, end) \ > + for (tdp_iter_start(&iter, root, min_level, start); \ > iter.valid && iter.gfn < end; \ > tdp_iter_next(&iter)) > > -#define for_each_tdp_pte(iter, root, root_level, start, end) \ > - for_each_tdp_pte_min_level(iter, root, root_level, PG_LEVEL_4K, start, end) > +#define for_each_tdp_pte(iter, root, start, end) \ > + for_each_tdp_pte_min_level(iter, root, PG_LEVEL_4K, start, end) > > tdp_ptep_t spte_to_child_pt(u64 pte, int level); > > -void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, > +void tdp_iter_start(struct tdp_iter *iter, struct kvm_mmu_page *root, > int min_level, gfn_t next_last_level_gfn); > void tdp_iter_next(struct tdp_iter *iter); > void tdp_iter_restart(struct tdp_iter *iter); > diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c > index 2221e074d8ea..5ca0fa659245 100644 > --- a/arch/x86/kvm/mmu/tdp_mmu.c > +++ b/arch/x86/kvm/mmu/tdp_mmu.c > @@ -632,7 +632,7 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm, > } > > #define tdp_root_for_each_pte(_iter, _root, _start, _end) \ > - for_each_tdp_pte(_iter, _root->spt, _root->role.level, _start, _end) > + for_each_tdp_pte(_iter, _root, _start, _end) > > #define tdp_root_for_each_leaf_pte(_iter, _root, _start, _end) \ > tdp_root_for_each_pte(_iter, _root, _start, _end) \ > @@ -642,8 +642,7 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm, > else > > #define tdp_mmu_for_each_pte(_iter, _mmu, _start, _end) \ > - for_each_tdp_pte(_iter, __va(_mmu->root_hpa), \ > - _mmu->shadow_root_level, _start, _end) > + for_each_tdp_pte(_iter, to_shadow_page(_mmu->root_hpa), _start, _end) > > static inline bool tdp_mmu_iter_need_resched(struct kvm *kvm, struct tdp_iter *iter) > { > @@ -738,8 +737,7 @@ static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, > > rcu_read_lock(); > > - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, > - min_level, start, end) { > + for_each_tdp_pte_min_level(iter, root, min_level, start, end) { > retry: > if (can_yield && > tdp_mmu_iter_cond_resched(kvm, &iter, flush, shared)) { > @@ -1201,8 +1199,7 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, > > BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL); > > - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, > - min_level, start, end) { > + for_each_tdp_pte_min_level(iter, root, min_level, start, end) { > retry: > if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true)) > continue; > @@ -1450,8 +1447,7 @@ static bool write_protect_gfn(struct kvm *kvm, struct kvm_mmu_page *root, > > rcu_read_lock(); > > - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, > - min_level, gfn, gfn + 1) { > + for_each_tdp_pte_min_level(iter, root, min_level, gfn, gfn + 1) { > if (!is_shadow_present_pte(iter.old_spte) || > !is_last_spte(iter.old_spte, iter.level)) > continue; > -- > 2.34.0.rc2.393.gf8c9666880-goog >
diff --git a/arch/x86/kvm/mmu/tdp_iter.c b/arch/x86/kvm/mmu/tdp_iter.c index b3ed302c1a35..92b3a075525a 100644 --- a/arch/x86/kvm/mmu/tdp_iter.c +++ b/arch/x86/kvm/mmu/tdp_iter.c @@ -39,9 +39,12 @@ void tdp_iter_restart(struct tdp_iter *iter) * Sets a TDP iterator to walk a pre-order traversal of the paging structure * rooted at root_pt, starting with the walk to translate next_last_level_gfn. */ -void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, +void tdp_iter_start(struct tdp_iter *iter, struct kvm_mmu_page *root, int min_level, gfn_t next_last_level_gfn) { + u64 *root_pt = root->spt; + int root_level = root->role.level; + WARN_ON(root_level < 1); WARN_ON(root_level > PT64_ROOT_MAX_LEVEL); diff --git a/arch/x86/kvm/mmu/tdp_iter.h b/arch/x86/kvm/mmu/tdp_iter.h index b1748b988d3a..ec1f58013428 100644 --- a/arch/x86/kvm/mmu/tdp_iter.h +++ b/arch/x86/kvm/mmu/tdp_iter.h @@ -51,17 +51,17 @@ struct tdp_iter { * Iterates over every SPTE mapping the GFN range [start, end) in a * preorder traversal. */ -#define for_each_tdp_pte_min_level(iter, root, root_level, min_level, start, end) \ - for (tdp_iter_start(&iter, root, root_level, min_level, start); \ +#define for_each_tdp_pte_min_level(iter, root, min_level, start, end) \ + for (tdp_iter_start(&iter, root, min_level, start); \ iter.valid && iter.gfn < end; \ tdp_iter_next(&iter)) -#define for_each_tdp_pte(iter, root, root_level, start, end) \ - for_each_tdp_pte_min_level(iter, root, root_level, PG_LEVEL_4K, start, end) +#define for_each_tdp_pte(iter, root, start, end) \ + for_each_tdp_pte_min_level(iter, root, PG_LEVEL_4K, start, end) tdp_ptep_t spte_to_child_pt(u64 pte, int level); -void tdp_iter_start(struct tdp_iter *iter, u64 *root_pt, int root_level, +void tdp_iter_start(struct tdp_iter *iter, struct kvm_mmu_page *root, int min_level, gfn_t next_last_level_gfn); void tdp_iter_next(struct tdp_iter *iter); void tdp_iter_restart(struct tdp_iter *iter); diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index 2221e074d8ea..5ca0fa659245 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -632,7 +632,7 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm, } #define tdp_root_for_each_pte(_iter, _root, _start, _end) \ - for_each_tdp_pte(_iter, _root->spt, _root->role.level, _start, _end) + for_each_tdp_pte(_iter, _root, _start, _end) #define tdp_root_for_each_leaf_pte(_iter, _root, _start, _end) \ tdp_root_for_each_pte(_iter, _root, _start, _end) \ @@ -642,8 +642,7 @@ static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm, else #define tdp_mmu_for_each_pte(_iter, _mmu, _start, _end) \ - for_each_tdp_pte(_iter, __va(_mmu->root_hpa), \ - _mmu->shadow_root_level, _start, _end) + for_each_tdp_pte(_iter, to_shadow_page(_mmu->root_hpa), _start, _end) static inline bool tdp_mmu_iter_need_resched(struct kvm *kvm, struct tdp_iter *iter) { @@ -738,8 +737,7 @@ static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, rcu_read_lock(); - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, - min_level, start, end) { + for_each_tdp_pte_min_level(iter, root, min_level, start, end) { retry: if (can_yield && tdp_mmu_iter_cond_resched(kvm, &iter, flush, shared)) { @@ -1201,8 +1199,7 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, BUG_ON(min_level > KVM_MAX_HUGEPAGE_LEVEL); - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, - min_level, start, end) { + for_each_tdp_pte_min_level(iter, root, min_level, start, end) { retry: if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true)) continue; @@ -1450,8 +1447,7 @@ static bool write_protect_gfn(struct kvm *kvm, struct kvm_mmu_page *root, rcu_read_lock(); - for_each_tdp_pte_min_level(iter, root->spt, root->role.level, - min_level, gfn, gfn + 1) { + for_each_tdp_pte_min_level(iter, root, min_level, gfn, gfn + 1) { if (!is_shadow_present_pte(iter.old_spte) || !is_last_spte(iter.old_spte, iter.level)) continue;
Instead of passing a pointer to the root page table and the root level seperately, pass in a pointer to the kvm_mmu_page that backs the root. This reduces the number of arguments by 1, cutting down on line lengths. No functional change intended. Signed-off-by: David Matlack <dmatlack@google.com> --- arch/x86/kvm/mmu/tdp_iter.c | 5 ++++- arch/x86/kvm/mmu/tdp_iter.h | 10 +++++----- arch/x86/kvm/mmu/tdp_mmu.c | 14 +++++--------- 3 files changed, 14 insertions(+), 15 deletions(-)