Re: [PATCH v4 25/36] sparc64: Implement the new page table range API

From: Mike Rapoport
Date: Wed Mar 15 2023 - 06:12:53 EST


On Wed, Mar 15, 2023 at 05:14:33AM +0000, Matthew Wilcox (Oracle) wrote:
> Add set_ptes(), update_mmu_cache_range(), flush_dcache_folio() and
> flush_icache_pages(). Convert the PG_dcache_dirty flag from being
> per-page to per-folio.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: sparclinux@xxxxxxxxxxxxxxx

Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>

> ---
> arch/sparc/include/asm/cacheflush_64.h | 18 ++++--
> arch/sparc/include/asm/pgtable_64.h | 24 ++++++--
> arch/sparc/kernel/smp_64.c | 56 +++++++++++-------
> arch/sparc/mm/init_64.c | 78 +++++++++++++++-----------
> arch/sparc/mm/tlb.c | 5 +-
> 5 files changed, 116 insertions(+), 65 deletions(-)
>
> diff --git a/arch/sparc/include/asm/cacheflush_64.h b/arch/sparc/include/asm/cacheflush_64.h
> index b9341836597e..a9a719f04d06 100644
> --- a/arch/sparc/include/asm/cacheflush_64.h
> +++ b/arch/sparc/include/asm/cacheflush_64.h
> @@ -35,20 +35,26 @@ void flush_icache_range(unsigned long start, unsigned long end);
> void __flush_icache_page(unsigned long);
>
> void __flush_dcache_page(void *addr, int flush_icache);
> -void flush_dcache_page_impl(struct page *page);
> +void flush_dcache_folio_impl(struct folio *folio);
> #ifdef CONFIG_SMP
> -void smp_flush_dcache_page_impl(struct page *page, int cpu);
> -void flush_dcache_page_all(struct mm_struct *mm, struct page *page);
> +void smp_flush_dcache_folio_impl(struct folio *folio, int cpu);
> +void flush_dcache_folio_all(struct mm_struct *mm, struct folio *folio);
> #else
> -#define smp_flush_dcache_page_impl(page,cpu) flush_dcache_page_impl(page)
> -#define flush_dcache_page_all(mm,page) flush_dcache_page_impl(page)
> +#define smp_flush_dcache_folio_impl(folio, cpu) flush_dcache_folio_impl(folio)
> +#define flush_dcache_folio_all(mm, folio) flush_dcache_folio_impl(folio)
> #endif
>
> void __flush_dcache_range(unsigned long start, unsigned long end);
> #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
> -void flush_dcache_page(struct page *page);
> +void flush_dcache_folio(struct folio *folio);
> +#define flush_dcache_folio flush_dcache_folio
> +static inline void flush_dcache_page(struct page *page)
> +{
> + flush_dcache_folio(page_folio(page));
> +}
>
> #define flush_icache_page(vma, pg) do { } while(0)
> +#define flush_icache_pages(vma, pg, nr) do { } while(0)
>
> void flush_ptrace_access(struct vm_area_struct *, struct page *,
> unsigned long uaddr, void *kaddr,
> diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
> index 2dc8d4641734..49c37000e1b1 100644
> --- a/arch/sparc/include/asm/pgtable_64.h
> +++ b/arch/sparc/include/asm/pgtable_64.h
> @@ -911,8 +911,19 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
> maybe_tlb_batch_add(mm, addr, ptep, orig, fullmm, PAGE_SHIFT);
> }
>
> -#define set_pte_at(mm,addr,ptep,pte) \
> - __set_pte_at((mm), (addr), (ptep), (pte), 0)
> +static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
> + pte_t *ptep, pte_t pte, unsigned int nr)
> +{
> + for (;;) {
> + __set_pte_at(mm, addr, ptep, pte, 0);
> + if (--nr == 0)
> + break;
> + ptep++;
> + pte_val(pte) += PAGE_SIZE;
> + addr += PAGE_SIZE;
> + }
> +}
> +#define set_ptes set_ptes
>
> #define pte_clear(mm,addr,ptep) \
> set_pte_at((mm), (addr), (ptep), __pte(0UL))
> @@ -931,8 +942,8 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
> \
> if (pfn_valid(this_pfn) && \
> (((old_addr) ^ (new_addr)) & (1 << 13))) \
> - flush_dcache_page_all(current->mm, \
> - pfn_to_page(this_pfn)); \
> + flush_dcache_folio_all(current->mm, \
> + page_folio(pfn_to_page(this_pfn))); \
> } \
> newpte; \
> })
> @@ -947,7 +958,10 @@ struct seq_file;
> void mmu_info(struct seq_file *);
>
> struct vm_area_struct;
> -void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
> +void update_mmu_cache_range(struct vm_area_struct *, unsigned long addr,
> + pte_t *ptep, unsigned int nr);
> +#define update_mmu_cache(vma, addr, ptep) \
> + update_mmu_cache_range(vma, addr, ptep, 1)
> #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> void update_mmu_cache_pmd(struct vm_area_struct *vma, unsigned long addr,
> pmd_t *pmd);
> diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
> index a55295d1b924..90ef8677ac89 100644
> --- a/arch/sparc/kernel/smp_64.c
> +++ b/arch/sparc/kernel/smp_64.c
> @@ -921,20 +921,26 @@ extern unsigned long xcall_flush_dcache_page_cheetah;
> #endif
> extern unsigned long xcall_flush_dcache_page_spitfire;
>
> -static inline void __local_flush_dcache_page(struct page *page)
> +static inline void __local_flush_dcache_folio(struct folio *folio)
> {
> + unsigned int i, nr = folio_nr_pages(folio);
> +
> #ifdef DCACHE_ALIASING_POSSIBLE
> - __flush_dcache_page(page_address(page),
> + for (i = 0; i < nr; i++)
> + __flush_dcache_page(folio_address(folio) + i * PAGE_SIZE,
> ((tlb_type == spitfire) &&
> - page_mapping_file(page) != NULL));
> + folio_flush_mapping(folio) != NULL));
> #else
> - if (page_mapping_file(page) != NULL &&
> - tlb_type == spitfire)
> - __flush_icache_page(__pa(page_address(page)));
> + if (folio_flush_mapping(folio) != NULL &&
> + tlb_type == spitfire) {
> + unsigned long pfn = folio_pfn(folio)
> + for (i = 0; i < nr; i++)
> + __flush_icache_page((pfn + i) * PAGE_SIZE);
> + }
> #endif
> }
>
> -void smp_flush_dcache_page_impl(struct page *page, int cpu)
> +void smp_flush_dcache_folio_impl(struct folio *folio, int cpu)
> {
> int this_cpu;
>
> @@ -948,14 +954,14 @@ void smp_flush_dcache_page_impl(struct page *page, int cpu)
> this_cpu = get_cpu();
>
> if (cpu == this_cpu) {
> - __local_flush_dcache_page(page);
> + __local_flush_dcache_folio(folio);
> } else if (cpu_online(cpu)) {
> - void *pg_addr = page_address(page);
> + void *pg_addr = folio_address(folio);
> u64 data0 = 0;
>
> if (tlb_type == spitfire) {
> data0 = ((u64)&xcall_flush_dcache_page_spitfire);
> - if (page_mapping_file(page) != NULL)
> + if (folio_flush_mapping(folio) != NULL)
> data0 |= ((u64)1 << 32);
> } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
> #ifdef DCACHE_ALIASING_POSSIBLE
> @@ -963,18 +969,23 @@ void smp_flush_dcache_page_impl(struct page *page, int cpu)
> #endif
> }
> if (data0) {
> - xcall_deliver(data0, __pa(pg_addr),
> - (u64) pg_addr, cpumask_of(cpu));
> + unsigned int i, nr = folio_nr_pages(folio);
> +
> + for (i = 0; i < nr; i++) {
> + xcall_deliver(data0, __pa(pg_addr),
> + (u64) pg_addr, cpumask_of(cpu));
> #ifdef CONFIG_DEBUG_DCFLUSH
> - atomic_inc(&dcpage_flushes_xcall);
> + atomic_inc(&dcpage_flushes_xcall);
> #endif
> + pg_addr += PAGE_SIZE;
> + }
> }
> }
>
> put_cpu();
> }
>
> -void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
> +void flush_dcache_folio_all(struct mm_struct *mm, struct folio *folio)
> {
> void *pg_addr;
> u64 data0;
> @@ -988,10 +999,10 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
> atomic_inc(&dcpage_flushes);
> #endif
> data0 = 0;
> - pg_addr = page_address(page);
> + pg_addr = folio_address(folio);
> if (tlb_type == spitfire) {
> data0 = ((u64)&xcall_flush_dcache_page_spitfire);
> - if (page_mapping_file(page) != NULL)
> + if (folio_flush_mapping(folio) != NULL)
> data0 |= ((u64)1 << 32);
> } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
> #ifdef DCACHE_ALIASING_POSSIBLE
> @@ -999,13 +1010,18 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
> #endif
> }
> if (data0) {
> - xcall_deliver(data0, __pa(pg_addr),
> - (u64) pg_addr, cpu_online_mask);
> + unsigned int i, nr = folio_nr_pages(folio);
> +
> + for (i = 0; i < nr; i++) {
> + xcall_deliver(data0, __pa(pg_addr),
> + (u64) pg_addr, cpu_online_mask);
> #ifdef CONFIG_DEBUG_DCFLUSH
> - atomic_inc(&dcpage_flushes_xcall);
> + atomic_inc(&dcpage_flushes_xcall);
> #endif
> + pg_addr += PAGE_SIZE;
> + }
> }
> - __local_flush_dcache_page(page);
> + __local_flush_dcache_folio(folio);
>
> preempt_enable();
> }
> diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
> index 04f9db0c3111..ab9aacbaf43c 100644
> --- a/arch/sparc/mm/init_64.c
> +++ b/arch/sparc/mm/init_64.c
> @@ -195,21 +195,26 @@ atomic_t dcpage_flushes_xcall = ATOMIC_INIT(0);
> #endif
> #endif
>
> -inline void flush_dcache_page_impl(struct page *page)
> +inline void flush_dcache_folio_impl(struct folio *folio)
> {
> + unsigned int i, nr = folio_nr_pages(folio);
> +
> BUG_ON(tlb_type == hypervisor);
> #ifdef CONFIG_DEBUG_DCFLUSH
> atomic_inc(&dcpage_flushes);
> #endif
>
> #ifdef DCACHE_ALIASING_POSSIBLE
> - __flush_dcache_page(page_address(page),
> - ((tlb_type == spitfire) &&
> - page_mapping_file(page) != NULL));
> + for (i = 0; i < nr; i++)
> + __flush_dcache_page(folio_address(folio) + i * PAGE_SIZE,
> + ((tlb_type == spitfire) &&
> + folio_flush_mapping(folio) != NULL));
> #else
> - if (page_mapping_file(page) != NULL &&
> - tlb_type == spitfire)
> - __flush_icache_page(__pa(page_address(page)));
> + if (folio_flush_mapping(folio) != NULL &&
> + tlb_type == spitfire) {
> + for (i = 0; i < nr; i++)
> + __flush_icache_page((pfn + i) * PAGE_SIZE);
> + }
> #endif
> }
>
> @@ -218,10 +223,10 @@ inline void flush_dcache_page_impl(struct page *page)
> #define PG_dcache_cpu_mask \
> ((1UL<<ilog2(roundup_pow_of_two(NR_CPUS)))-1UL)
>
> -#define dcache_dirty_cpu(page) \
> - (((page)->flags >> PG_dcache_cpu_shift) & PG_dcache_cpu_mask)
> +#define dcache_dirty_cpu(folio) \
> + (((folio)->flags >> PG_dcache_cpu_shift) & PG_dcache_cpu_mask)
>
> -static inline void set_dcache_dirty(struct page *page, int this_cpu)
> +static inline void set_dcache_dirty(struct folio *folio, int this_cpu)
> {
> unsigned long mask = this_cpu;
> unsigned long non_cpu_bits;
> @@ -238,11 +243,11 @@ static inline void set_dcache_dirty(struct page *page, int this_cpu)
> "bne,pn %%xcc, 1b\n\t"
> " nop"
> : /* no outputs */
> - : "r" (mask), "r" (non_cpu_bits), "r" (&page->flags)
> + : "r" (mask), "r" (non_cpu_bits), "r" (&folio->flags)
> : "g1", "g7");
> }
>
> -static inline void clear_dcache_dirty_cpu(struct page *page, unsigned long cpu)
> +static inline void clear_dcache_dirty_cpu(struct folio *folio, unsigned long cpu)
> {
> unsigned long mask = (1UL << PG_dcache_dirty);
>
> @@ -260,7 +265,7 @@ static inline void clear_dcache_dirty_cpu(struct page *page, unsigned long cpu)
> " nop\n"
> "2:"
> : /* no outputs */
> - : "r" (cpu), "r" (mask), "r" (&page->flags),
> + : "r" (cpu), "r" (mask), "r" (&folio->flags),
> "i" (PG_dcache_cpu_mask),
> "i" (PG_dcache_cpu_shift)
> : "g1", "g7");
> @@ -284,9 +289,10 @@ static void flush_dcache(unsigned long pfn)
>
> page = pfn_to_page(pfn);
> if (page) {
> + struct folio *folio = page_folio(page);
> unsigned long pg_flags;
>
> - pg_flags = page->flags;
> + pg_flags = folio->flags;
> if (pg_flags & (1UL << PG_dcache_dirty)) {
> int cpu = ((pg_flags >> PG_dcache_cpu_shift) &
> PG_dcache_cpu_mask);
> @@ -296,11 +302,11 @@ static void flush_dcache(unsigned long pfn)
> * in the SMP case.
> */
> if (cpu == this_cpu)
> - flush_dcache_page_impl(page);
> + flush_dcache_folio_impl(folio);
> else
> - smp_flush_dcache_page_impl(page, cpu);
> + smp_flush_dcache_folio_impl(folio, cpu);
>
> - clear_dcache_dirty_cpu(page, cpu);
> + clear_dcache_dirty_cpu(folio, cpu);
>
> put_cpu();
> }
> @@ -388,12 +394,14 @@ bool __init arch_hugetlb_valid_size(unsigned long size)
> }
> #endif /* CONFIG_HUGETLB_PAGE */
>
> -void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
> +void update_mmu_cache_range(struct vm_area_struct *vma, unsigned long address,
> + pte_t *ptep, unsigned int nr)
> {
> struct mm_struct *mm;
> unsigned long flags;
> bool is_huge_tsb;
> pte_t pte = *ptep;
> + unsigned int i;
>
> if (tlb_type != hypervisor) {
> unsigned long pfn = pte_pfn(pte);
> @@ -440,15 +448,21 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *
> }
> }
> #endif
> - if (!is_huge_tsb)
> - __update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT,
> - address, pte_val(pte));
> + if (!is_huge_tsb) {
> + for (i = 0; i < nr; i++) {
> + __update_mmu_tsb_insert(mm, MM_TSB_BASE, PAGE_SHIFT,
> + address, pte_val(pte));
> + address += PAGE_SIZE;
> + pte_val(pte) += PAGE_SIZE;
> + }
> + }
>
> spin_unlock_irqrestore(&mm->context.lock, flags);
> }
>
> -void flush_dcache_page(struct page *page)
> +void flush_dcache_folio(struct folio *folio)
> {
> + unsigned long pfn = folio_pfn(folio);
> struct address_space *mapping;
> int this_cpu;
>
> @@ -459,35 +473,35 @@ void flush_dcache_page(struct page *page)
> * is merely the zero page. The 'bigcore' testcase in GDB
> * causes this case to run millions of times.
> */
> - if (page == ZERO_PAGE(0))
> + if (is_zero_pfn(pfn))
> return;
>
> this_cpu = get_cpu();
>
> - mapping = page_mapping_file(page);
> + mapping = folio_flush_mapping(folio);
> if (mapping && !mapping_mapped(mapping)) {
> - int dirty = test_bit(PG_dcache_dirty, &page->flags);
> + bool dirty = test_bit(PG_dcache_dirty, &folio->flags);
> if (dirty) {
> - int dirty_cpu = dcache_dirty_cpu(page);
> + int dirty_cpu = dcache_dirty_cpu(folio);
>
> if (dirty_cpu == this_cpu)
> goto out;
> - smp_flush_dcache_page_impl(page, dirty_cpu);
> + smp_flush_dcache_folio_impl(folio, dirty_cpu);
> }
> - set_dcache_dirty(page, this_cpu);
> + set_dcache_dirty(folio, this_cpu);
> } else {
> /* We could delay the flush for the !page_mapping
> * case too. But that case is for exec env/arg
> * pages and those are %99 certainly going to get
> * faulted into the tlb (and thus flushed) anyways.
> */
> - flush_dcache_page_impl(page);
> + flush_dcache_folio_impl(folio);
> }
>
> out:
> put_cpu();
> }
> -EXPORT_SYMBOL(flush_dcache_page);
> +EXPORT_SYMBOL(flush_dcache_folio);
>
> void __kprobes flush_icache_range(unsigned long start, unsigned long end)
> {
> @@ -2280,10 +2294,10 @@ void __init paging_init(void)
> setup_page_offset();
>
> /* These build time checkes make sure that the dcache_dirty_cpu()
> - * page->flags usage will work.
> + * folio->flags usage will work.
> *
> * When a page gets marked as dcache-dirty, we store the
> - * cpu number starting at bit 32 in the page->flags. Also,
> + * cpu number starting at bit 32 in the folio->flags. Also,
> * functions like clear_dcache_dirty_cpu use the cpu mask
> * in 13-bit signed-immediate instruction fields.
> */
> diff --git a/arch/sparc/mm/tlb.c b/arch/sparc/mm/tlb.c
> index 9a725547578e..3fa6a070912d 100644
> --- a/arch/sparc/mm/tlb.c
> +++ b/arch/sparc/mm/tlb.c
> @@ -118,6 +118,7 @@ void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
> unsigned long paddr, pfn = pte_pfn(orig);
> struct address_space *mapping;
> struct page *page;
> + struct folio *folio;
>
> if (!pfn_valid(pfn))
> goto no_cache_flush;
> @@ -127,13 +128,13 @@ void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
> goto no_cache_flush;
>
> /* A real file page? */
> - mapping = page_mapping_file(page);
> + mapping = folio_flush_mapping(folio);
> if (!mapping)
> goto no_cache_flush;
>
> paddr = (unsigned long) page_address(page);
> if ((paddr ^ vaddr) & (1 << 13))
> - flush_dcache_page_all(mm, page);
> + flush_dcache_folio_all(mm, folio);
> }
>
> no_cache_flush:
> --
> 2.39.2
>
>

--
Sincerely yours,
Mike.