[PATCH v6 09/18] ia64/tlb: Conver to generic mmu_gather

From: Peter Zijlstra
Date: Tue Feb 19 2019 - 05:34:02 EST


Generic mmu_gather provides everything ia64 needs (range tracking).

Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Nick Piggin <npiggin@xxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/ia64/include/asm/tlb.h | 256 ---------------------------------------
arch/ia64/include/asm/tlbflush.h | 25 +++
arch/ia64/mm/tlb.c | 23 +++
3 files changed, 47 insertions(+), 257 deletions(-)

--- a/arch/ia64/include/asm/tlb.h
+++ b/arch/ia64/include/asm/tlb.h
@@ -47,262 +47,8 @@
#include <asm/tlbflush.h>
#include <asm/machvec.h>

-/*
- * If we can't allocate a page to make a big batch of page pointers
- * to work on, then just handle a few from the on-stack structure.
- */
-#define IA64_GATHER_BUNDLE 8
-
-struct mmu_gather {
- struct mm_struct *mm;
- unsigned int nr;
- unsigned int max;
- unsigned char fullmm; /* non-zero means full mm flush */
- unsigned char need_flush; /* really unmapped some PTEs? */
- unsigned long start, end;
- unsigned long start_addr;
- unsigned long end_addr;
- struct page **pages;
- struct page *local[IA64_GATHER_BUNDLE];
-};
-
-struct ia64_tr_entry {
- u64 ifa;
- u64 itir;
- u64 pte;
- u64 rr;
-}; /*Record for tr entry!*/
-
-extern int ia64_itr_entry(u64 target_mask, u64 va, u64 pte, u64 log_size);
-extern void ia64_ptr_entry(u64 target_mask, int slot);
-
-extern struct ia64_tr_entry *ia64_idtrs[NR_CPUS];
-
-/*
- region register macros
-*/
-#define RR_TO_VE(val) (((val) >> 0) & 0x0000000000000001)
-#define RR_VE(val) (((val) & 0x0000000000000001) << 0)
-#define RR_VE_MASK 0x0000000000000001L
-#define RR_VE_SHIFT 0
-#define RR_TO_PS(val) (((val) >> 2) & 0x000000000000003f)
-#define RR_PS(val) (((val) & 0x000000000000003f) << 2)
-#define RR_PS_MASK 0x00000000000000fcL
-#define RR_PS_SHIFT 2
-#define RR_RID_MASK 0x00000000ffffff00L
-#define RR_TO_RID(val) ((val >> 8) & 0xffffff)
-
-static inline void
-ia64_tlb_flush_mmu_tlbonly(struct mmu_gather *tlb, unsigned long start, unsigned long end)
-{
- tlb->need_flush = 0;
-
- if (tlb->fullmm) {
- /*
- * Tearing down the entire address space. This happens both as a result
- * of exit() and execve(). The latter case necessitates the call to
- * flush_tlb_mm() here.
- */
- flush_tlb_mm(tlb->mm);
- } else if (unlikely (end - start >= 1024*1024*1024*1024UL
- || REGION_NUMBER(start) != REGION_NUMBER(end - 1)))
- {
- /*
- * If we flush more than a tera-byte or across regions, we're probably
- * better off just flushing the entire TLB(s). This should be very rare
- * and is not worth optimizing for.
- */
- flush_tlb_all();
- } else {
- /*
- * flush_tlb_range() takes a vma instead of a mm pointer because
- * some architectures want the vm_flags for ITLB/DTLB flush.
- */
- struct vm_area_struct vma = TLB_FLUSH_VMA(tlb->mm, 0);
-
- /* flush the address range from the tlb: */
- flush_tlb_range(&vma, start, end);
- /* now flush the virt. page-table area mapping the address range: */
- flush_tlb_range(&vma, ia64_thash(start), ia64_thash(end));
- }
-
-}
-
-static inline void
-ia64_tlb_flush_mmu_free(struct mmu_gather *tlb)
-{
- unsigned long i;
- unsigned int nr;
-
- /* lastly, release the freed pages */
- nr = tlb->nr;
-
- tlb->nr = 0;
- tlb->start_addr = ~0UL;
- for (i = 0; i < nr; ++i)
- free_page_and_swap_cache(tlb->pages[i]);
-}
-
-/*
- * Flush the TLB for address range START to END and, if not in fast mode, release the
- * freed pages that where gathered up to this point.
- */
-static inline void
-ia64_tlb_flush_mmu (struct mmu_gather *tlb, unsigned long start, unsigned long end)
-{
- if (!tlb->need_flush)
- return;
- ia64_tlb_flush_mmu_tlbonly(tlb, start, end);
- ia64_tlb_flush_mmu_free(tlb);
-}
-
-static inline void __tlb_alloc_page(struct mmu_gather *tlb)
-{
- unsigned long addr = __get_free_pages(GFP_NOWAIT | __GFP_NOWARN, 0);
-
- if (addr) {
- tlb->pages = (void *)addr;
- tlb->max = PAGE_SIZE / sizeof(void *);
- }
-}
-
-
-static inline void
-arch_tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
- unsigned long start, unsigned long end)
-{
- tlb->mm = mm;
- tlb->max = ARRAY_SIZE(tlb->local);
- tlb->pages = tlb->local;
- tlb->nr = 0;
- tlb->fullmm = !(start | (end+1));
- tlb->start = start;
- tlb->end = end;
- tlb->start_addr = ~0UL;
-}
-
-/*
- * Called at the end of the shootdown operation to free up any resources that were
- * collected.
- */
-static inline void
-arch_tlb_finish_mmu(struct mmu_gather *tlb,
- unsigned long start, unsigned long end, bool force)
-{
- if (force)
- tlb->need_flush = 1;
- /*
- * Note: tlb->nr may be 0 at this point, so we can't rely on tlb->start_addr and
- * tlb->end_addr.
- */
- ia64_tlb_flush_mmu(tlb, start, end);
-
- /* keep the page table cache within bounds */
- check_pgt_cache();
-
- if (tlb->pages != tlb->local)
- free_pages((unsigned long)tlb->pages, 0);
-}
-
-/*
- * Logically, this routine frees PAGE. On MP machines, the actual freeing of the page
- * must be delayed until after the TLB has been flushed (see comments at the beginning of
- * this file).
- */
-static inline bool __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
-{
- tlb->need_flush = 1;
-
- if (!tlb->nr && tlb->pages == tlb->local)
- __tlb_alloc_page(tlb);
-
- tlb->pages[tlb->nr++] = page;
- VM_WARN_ON(tlb->nr > tlb->max);
- if (tlb->nr == tlb->max)
- return true;
- return false;
-}
-
-static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
-{
- ia64_tlb_flush_mmu_tlbonly(tlb, tlb->start_addr, tlb->end_addr);
-}
-
-static inline void tlb_flush_mmu_free(struct mmu_gather *tlb)
-{
- ia64_tlb_flush_mmu_free(tlb);
-}
-
-static inline void tlb_flush_mmu(struct mmu_gather *tlb)
-{
- ia64_tlb_flush_mmu(tlb, tlb->start_addr, tlb->end_addr);
-}
-
-static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
-{
- if (__tlb_remove_page(tlb, page))
- tlb_flush_mmu(tlb);
-}
-
-static inline bool __tlb_remove_page_size(struct mmu_gather *tlb,
- struct page *page, int page_size)
-{
- return __tlb_remove_page(tlb, page);
-}
-
-static inline void tlb_remove_page_size(struct mmu_gather *tlb,
- struct page *page, int page_size)
-{
- return tlb_remove_page(tlb, page);
-}
-
-/*
- * Remove TLB entry for PTE mapped at virtual address ADDRESS. This is called for any
- * PTE, not just those pointing to (normal) physical memory.
- */
-static inline void
-__tlb_remove_tlb_entry (struct mmu_gather *tlb, pte_t *ptep, unsigned long address)
-{
- if (tlb->start_addr == ~0UL)
- tlb->start_addr = address;
- tlb->end_addr = address + PAGE_SIZE;
-}
-
#define tlb_migrate_finish(mm) platform_tlb_migrate_finish(mm)

-#define tlb_start_vma(tlb, vma) do { } while (0)
-#define tlb_end_vma(tlb, vma) do { } while (0)
-
-#define tlb_remove_tlb_entry(tlb, ptep, addr) \
-do { \
- tlb->need_flush = 1; \
- __tlb_remove_tlb_entry(tlb, ptep, addr); \
-} while (0)
-
-#define tlb_remove_huge_tlb_entry(h, tlb, ptep, address) \
- tlb_remove_tlb_entry(tlb, ptep, address)
-
-static inline void tlb_change_page_size(struct mmu_gather *tlb,
- unsigned int page_size)
-{
-}
-
-#define pte_free_tlb(tlb, ptep, address) \
-do { \
- tlb->need_flush = 1; \
- __pte_free_tlb(tlb, ptep, address); \
-} while (0)
-
-#define pmd_free_tlb(tlb, ptep, address) \
-do { \
- tlb->need_flush = 1; \
- __pmd_free_tlb(tlb, ptep, address); \
-} while (0)
-
-#define pud_free_tlb(tlb, pudp, address) \
-do { \
- tlb->need_flush = 1; \
- __pud_free_tlb(tlb, pudp, address); \
-} while (0)
+#include <asm-generic/tlb.h>

#endif /* _ASM_IA64_TLB_H */
--- a/arch/ia64/include/asm/tlbflush.h
+++ b/arch/ia64/include/asm/tlbflush.h
@@ -14,6 +14,31 @@
#include <asm/mmu_context.h>
#include <asm/page.h>

+struct ia64_tr_entry {
+ u64 ifa;
+ u64 itir;
+ u64 pte;
+ u64 rr;
+}; /*Record for tr entry!*/
+
+extern int ia64_itr_entry(u64 target_mask, u64 va, u64 pte, u64 log_size);
+extern void ia64_ptr_entry(u64 target_mask, int slot);
+extern struct ia64_tr_entry *ia64_idtrs[NR_CPUS];
+
+/*
+ region register macros
+*/
+#define RR_TO_VE(val) (((val) >> 0) & 0x0000000000000001)
+#define RR_VE(val) (((val) & 0x0000000000000001) << 0)
+#define RR_VE_MASK 0x0000000000000001L
+#define RR_VE_SHIFT 0
+#define RR_TO_PS(val) (((val) >> 2) & 0x000000000000003f)
+#define RR_PS(val) (((val) & 0x000000000000003f) << 2)
+#define RR_PS_MASK 0x00000000000000fcL
+#define RR_PS_SHIFT 2
+#define RR_RID_MASK 0x00000000ffffff00L
+#define RR_TO_RID(val) ((val >> 8) & 0xffffff)
+
/*
* Now for some TLB flushing routines. This is the kind of stuff that
* can be very expensive, so try to avoid them whenever possible.
--- a/arch/ia64/mm/tlb.c
+++ b/arch/ia64/mm/tlb.c
@@ -297,8 +297,8 @@ local_flush_tlb_all (void)
ia64_srlz_i(); /* srlz.i implies srlz.d */
}

-void
-flush_tlb_range (struct vm_area_struct *vma, unsigned long start,
+static void
+__flush_tlb_range (struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
@@ -335,6 +335,25 @@ flush_tlb_range (struct vm_area_struct *
preempt_enable();
ia64_srlz_i(); /* srlz.i implies srlz.d */
}
+
+void flush_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ if (unlikely(end - start >= 1024*1024*1024*1024UL
+ || REGION_NUMBER(start) != REGION_NUMBER(end - 1))) {
+ /*
+ * If we flush more than a tera-byte or across regions, we're
+ * probably better off just flushing the entire TLB(s). This
+ * should be very rare and is not worth optimizing for.
+ */
+ flush_tlb_all();
+ } else {
+ /* flush the address range from the tlb */
+ __flush_tlb_range(vma, start, end);
+ /* flush the virt. page-table area mapping the addr range */
+ __flush_tlb_range(vma, ia64_thash(start), ia64_thash(end));
+ }
+}
EXPORT_SYMBOL(flush_tlb_range);

void ia64_tlb_init(void)