[RFC][PATCH 02/11] asm-generic/tlb: Provide HAVE_MMU_GATHER_PAGE_SIZE

From: Peter Zijlstra
Date: Thu Sep 13 2018 - 05:29:31 EST


Move the mmu_gather::page_size things into the generic code instead of
powerpc specific bits.

Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/Kconfig | 3 +++
arch/arm/include/asm/tlb.h | 3 +--
arch/ia64/include/asm/tlb.h | 3 +--
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/tlb.h | 17 -----------------
arch/s390/include/asm/tlb.h | 4 +---
arch/sh/include/asm/tlb.h | 4 +---
arch/um/include/asm/tlb.h | 4 +---
include/asm-generic/tlb.h | 25 +++++++++++++------------
mm/huge_memory.c | 4 ++--
mm/hugetlb.c | 2 +-
mm/madvise.c | 2 +-
mm/memory.c | 4 ++--
mm/mmu_gather.c | 5 +++++
14 files changed, 33 insertions(+), 48 deletions(-)

--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -365,6 +365,9 @@ config HAVE_RCU_TABLE_FREE
config HAVE_RCU_TABLE_INVALIDATE
bool

+config HAVE_MMU_GATHER_PAGE_SIZE
+ bool
+
config ARCH_HAVE_NMI_SAFE_CMPXCHG
bool

--- a/arch/arm/include/asm/tlb.h
+++ b/arch/arm/include/asm/tlb.h
@@ -286,8 +286,7 @@ tlb_remove_pmd_tlb_entry(struct mmu_gath

#define tlb_migrate_finish(mm) do { } while (0)

-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
+static inline void tlb_change_page_size(struct mmu_gather *tlb,
unsigned int page_size)
{
}
--- a/arch/ia64/include/asm/tlb.h
+++ b/arch/ia64/include/asm/tlb.h
@@ -282,8 +282,7 @@ do { \
#define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \
tlb_remove_tlb_entry(tlb, ptep, address)

-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
+static inline void tlb_change_page_size(struct mmu_gather *tlb,
unsigned int page_size)
{
}
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -216,6 +216,7 @@ config PPC
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
select HAVE_RCU_TABLE_FREE if SMP
+ select HAVE_MMU_GATHER_PAGE_SIZE
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_RELIABLE_STACKTRACE if PPC64 && CPU_LITTLE_ENDIAN
select HAVE_SYSCALL_TRACEPOINTS
--- a/arch/powerpc/include/asm/tlb.h
+++ b/arch/powerpc/include/asm/tlb.h
@@ -27,7 +27,6 @@
#define tlb_start_vma(tlb, vma) do { } while (0)
#define tlb_end_vma(tlb, vma) do { } while (0)
#define __tlb_remove_tlb_entry __tlb_remove_tlb_entry
-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change

extern void tlb_flush(struct mmu_gather *tlb);

@@ -46,22 +45,6 @@ static inline void __tlb_remove_tlb_entr
#endif
}

-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
- unsigned int page_size)
-{
- if (!tlb->page_size)
- tlb->page_size = page_size;
- else if (tlb->page_size != page_size) {
- if (!tlb->fullmm)
- tlb_flush_mmu(tlb);
- /*
- * update the page size after flush for the new
- * mmu_gather.
- */
- tlb->page_size = page_size;
- }
-}
-
#ifdef CONFIG_SMP
static inline int mm_is_core_local(struct mm_struct *mm)
{
--- a/arch/s390/include/asm/tlb.h
+++ b/arch/s390/include/asm/tlb.h
@@ -180,9 +180,7 @@ static inline void pud_free_tlb(struct m
#define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \
tlb_remove_tlb_entry(tlb, ptep, address)

-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
- unsigned int page_size)
+static inline void tlb_change_page_size(struct mmu_gather *tlb, unsigned int page_size)
{
}

--- a/arch/sh/include/asm/tlb.h
+++ b/arch/sh/include/asm/tlb.h
@@ -127,9 +127,7 @@ static inline void tlb_remove_page_size(
return tlb_remove_page(tlb, page);
}

-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
- unsigned int page_size)
+static inline void tlb_change_page_size(struct mmu_gather *tlb, unsigned int page_size)
{
}

--- a/arch/um/include/asm/tlb.h
+++ b/arch/um/include/asm/tlb.h
@@ -146,9 +146,7 @@ static inline void tlb_remove_page_size(
#define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \
tlb_remove_tlb_entry(tlb, ptep, address)

-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
- unsigned int page_size)
+static inline void tlb_change_page_size(struct mmu_gather *tlb, unsigned int page_size)
{
}

--- a/include/asm-generic/tlb.h
+++ b/include/asm-generic/tlb.h
@@ -240,11 +240,15 @@ struct mmu_gather {
unsigned int cleared_puds : 1;
unsigned int cleared_p4ds : 1;

+ unsigned int batch_count;
+
struct mmu_gather_batch *active;
struct mmu_gather_batch local;
struct page *__pages[MMU_GATHER_BUNDLE];
- unsigned int batch_count;
- int page_size;
+
+#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
+ unsigned int page_size;
+#endif
};

void arch_tlb_gather_mmu(struct mmu_gather *tlb,
@@ -310,21 +314,18 @@ static inline void tlb_remove_page(struc
return tlb_remove_page_size(tlb, page, PAGE_SIZE);
}

-#ifndef tlb_remove_check_page_size_change
-#define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
-static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
+static inline void tlb_change_page_size(struct mmu_gather *tlb,
unsigned int page_size)
{
- /*
- * We don't care about page size change, just update
- * mmu_gather page size here so that debug checks
- * doesn't throw false warning.
- */
-#ifdef CONFIG_DEBUG_VM
+#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
+ if (tlb->page_size && tlb->page_size != page_size) {
+ if (!tlb->fullmm)
+ tlb_flush_mmu(tlb);
+ }
+
tlb->page_size = page_size;
#endif
}
-#endif

static inline unsigned long tlb_get_unmap_shift(struct mmu_gather *tlb)
{
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1617,7 +1617,7 @@ bool madvise_free_huge_pmd(struct mmu_ga
struct mm_struct *mm = tlb->mm;
bool ret = false;

- tlb_remove_check_page_size_change(tlb, HPAGE_PMD_SIZE);
+ tlb_change_page_size(tlb, HPAGE_PMD_SIZE);

ptl = pmd_trans_huge_lock(pmd, vma);
if (!ptl)
@@ -1693,7 +1693,7 @@ int zap_huge_pmd(struct mmu_gather *tlb,
pmd_t orig_pmd;
spinlock_t *ptl;

- tlb_remove_check_page_size_change(tlb, HPAGE_PMD_SIZE);
+ tlb_change_page_size(tlb, HPAGE_PMD_SIZE);

ptl = __pmd_trans_huge_lock(pmd, vma);
if (!ptl)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3337,7 +3337,7 @@ void __unmap_hugepage_range(struct mmu_g
* This is a hugetlb vma, all the pte entries should point
* to huge page.
*/
- tlb_remove_check_page_size_change(tlb, sz);
+ tlb_change_page_size(tlb, sz);
tlb_start_vma(tlb, vma);
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
address = start;
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -328,7 +328,7 @@ static int madvise_free_pte_range(pmd_t
if (pmd_trans_unstable(pmd))
return 0;

- tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
+ tlb_change_page_size(tlb, PAGE_SIZE);
orig_pte = pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
flush_tlb_batched_pending(mm);
arch_enter_lazy_mmu_mode();
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -355,7 +355,7 @@ void free_pgd_range(struct mmu_gather *t
* We add page table cache pages with PAGE_SIZE,
* (see pte_free_tlb()), flush the tlb if we need
*/
- tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
+ tlb_change_page_size(tlb, PAGE_SIZE);
pgd = pgd_offset(tlb->mm, addr);
do {
next = pgd_addr_end(addr, end);
@@ -1046,7 +1046,7 @@ static unsigned long zap_pte_range(struc
pte_t *pte;
swp_entry_t entry;

- tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
+ tlb_change_page_size(tlb, PAGE_SIZE);
again:
init_rss_vec(rss);
start_pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
--- a/mm/mmu_gather.c
+++ b/mm/mmu_gather.c
@@ -58,7 +58,9 @@ void arch_tlb_gather_mmu(struct mmu_gath
#ifdef CONFIG_HAVE_RCU_TABLE_FREE
tlb->batch = NULL;
#endif
+#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
tlb->page_size = 0;
+#endif

__tlb_reset_range(tlb);
}
@@ -121,7 +123,10 @@ bool __tlb_remove_page_size(struct mmu_g
struct mmu_gather_batch *batch;

VM_BUG_ON(!tlb->end);
+
+#ifdef CONFIG_HAVE_MMU_GATHER_PAGE_SIZE
VM_WARN_ON(tlb->page_size != page_size);
+#endif

batch = tlb->active;
/*