powerpc/64s/hash: remove user SLB data from the paca
authorNicholas Piggin <npiggin@gmail.com>
Fri, 14 Sep 2018 15:30:52 +0000 (01:30 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Wed, 19 Sep 2018 12:01:46 +0000 (22:01 +1000)
User SLB mappig data is copied into the PACA from the mm->context so
it can be accessed by the SLB miss handlers.

After the C conversion, SLB miss handlers now run with relocation on,
and user SLB misses are able to take recursive kernel SLB misses, so
the user SLB mapping data can be removed from the paca and accessed
directly.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/include/asm/book3s/64/mmu-hash.h
arch/powerpc/include/asm/paca.h
arch/powerpc/kernel/asm-offsets.c
arch/powerpc/kernel/paca.c
arch/powerpc/mm/hash_utils_64.c
arch/powerpc/mm/mmu_context.c
arch/powerpc/mm/slb.c
arch/powerpc/mm/slice.c

index e0e4ce8f77d6d8940b9cbe96e783478e72aa9ce9..d3064c7d1b1f604f82e0efda341fa18f8f2bc45d 100644 (file)
@@ -501,6 +501,7 @@ struct slb_entry {
 };
 
 extern void slb_initialize(void);
+extern void core_flush_all_slbs(struct mm_struct *mm);
 extern void slb_flush_and_rebolt(void);
 void slb_flush_all_realmode(void);
 void __slb_restore_bolted_realmode(void);
index 7b6e23af38082fa7892befdc2f39371b1cbfc36d..8144d673541a74e78c440ba35fe3dce791542c5c 100644 (file)
@@ -143,18 +143,6 @@ struct paca_struct {
        struct tlb_core_data tcd;
 #endif /* CONFIG_PPC_BOOK3E */
 
-#ifdef CONFIG_PPC_BOOK3S
-       mm_context_id_t mm_ctx_id;
-#ifdef CONFIG_PPC_MM_SLICES
-       unsigned char mm_ctx_low_slices_psize[BITS_PER_LONG / BITS_PER_BYTE];
-       unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
-       unsigned long mm_ctx_slb_addr_limit;
-#else
-       u16 mm_ctx_user_psize;
-       u16 mm_ctx_sllp;
-#endif
-#endif
-
        /*
         * then miscellaneous read-write fields
         */
@@ -258,7 +246,6 @@ struct paca_struct {
 #endif /* CONFIG_PPC_BOOK3S_64 */
 } ____cacheline_aligned;
 
-extern void copy_mm_to_paca(struct mm_struct *mm);
 extern struct paca_struct **paca_ptrs;
 extern void initialise_paca(struct paca_struct *new_paca, int cpu);
 extern void setup_paca(struct paca_struct *new_paca);
index 89cf15566c4e80ba4e81d500e1d86f204e1241b2..ce3ac40fd96ea472acd4e88fb89764b1e1445bfa 100644 (file)
@@ -181,15 +181,6 @@ int main(void)
        OFFSET(PACAIRQSOFTMASK, paca_struct, irq_soft_mask);
        OFFSET(PACAIRQHAPPENED, paca_struct, irq_happened);
        OFFSET(PACA_FTRACE_ENABLED, paca_struct, ftrace_enabled);
-#ifdef CONFIG_PPC_BOOK3S
-       OFFSET(PACACONTEXTID, paca_struct, mm_ctx_id);
-#ifdef CONFIG_PPC_MM_SLICES
-       OFFSET(PACALOWSLICESPSIZE, paca_struct, mm_ctx_low_slices_psize);
-       OFFSET(PACAHIGHSLICEPSIZE, paca_struct, mm_ctx_high_slices_psize);
-       OFFSET(PACA_SLB_ADDR_LIMIT, paca_struct, mm_ctx_slb_addr_limit);
-       DEFINE(MMUPSIZEDEFSIZE, sizeof(struct mmu_psize_def));
-#endif /* CONFIG_PPC_MM_SLICES */
-#endif
 
 #ifdef CONFIG_PPC_BOOK3E
        OFFSET(PACAPGD, paca_struct, pgd);
index 0ee3e6d50f2885d519462af046e19560ca4ace8e..0cf84e30d1cde755113f9d5460880c9126367b02 100644 (file)
@@ -258,25 +258,3 @@ void __init free_unused_pacas(void)
        printk(KERN_DEBUG "Allocated %u bytes for %u pacas\n",
                        paca_ptrs_size + paca_struct_size, nr_cpu_ids);
 }
-
-void copy_mm_to_paca(struct mm_struct *mm)
-{
-#ifdef CONFIG_PPC_BOOK3S
-       mm_context_t *context = &mm->context;
-
-       get_paca()->mm_ctx_id = context->id;
-#ifdef CONFIG_PPC_MM_SLICES
-       VM_BUG_ON(!mm->context.slb_addr_limit);
-       get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
-       memcpy(&get_paca()->mm_ctx_low_slices_psize,
-              &context->low_slices_psize, sizeof(context->low_slices_psize));
-       memcpy(&get_paca()->mm_ctx_high_slices_psize,
-              &context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
-#else /* CONFIG_PPC_MM_SLICES */
-       get_paca()->mm_ctx_user_psize = context->user_psize;
-       get_paca()->mm_ctx_sllp = context->sllp;
-#endif
-#else /* !CONFIG_PPC_BOOK3S */
-       return;
-#endif
-}
index f23a89d8e4ce6c8fecf0816d23b88d621c68428b..88c95dc8b141fad5182adb3b2ae7db86607877c0 100644 (file)
@@ -1088,16 +1088,16 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
 }
 
 #ifdef CONFIG_PPC_MM_SLICES
-static unsigned int get_paca_psize(unsigned long addr)
+static unsigned int get_psize(struct mm_struct *mm, unsigned long addr)
 {
        unsigned char *psizes;
        unsigned long index, mask_index;
 
        if (addr < SLICE_LOW_TOP) {
-               psizes = get_paca()->mm_ctx_low_slices_psize;
+               psizes = mm->context.low_slices_psize;
                index = GET_LOW_SLICE_INDEX(addr);
        } else {
-               psizes = get_paca()->mm_ctx_high_slices_psize;
+               psizes = mm->context.high_slices_psize;
                index = GET_HIGH_SLICE_INDEX(addr);
        }
        mask_index = index & 0x1;
@@ -1105,9 +1105,9 @@ static unsigned int get_paca_psize(unsigned long addr)
 }
 
 #else
-unsigned int get_paca_psize(unsigned long addr)
+unsigned int get_psize(struct mm_struct *mm, unsigned long addr)
 {
-       return get_paca()->mm_ctx_user_psize;
+       return mm->context.user_psize;
 }
 #endif
 
@@ -1118,15 +1118,11 @@ unsigned int get_paca_psize(unsigned long addr)
 #ifdef CONFIG_PPC_64K_PAGES
 void demote_segment_4k(struct mm_struct *mm, unsigned long addr)
 {
-       if (get_slice_psize(mm, addr) == MMU_PAGE_4K)
+       if (get_psize(mm, addr) == MMU_PAGE_4K)
                return;
        slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K);
        copro_flush_all_slbs(mm);
-       if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) {
-
-               copy_mm_to_paca(mm);
-               slb_flush_and_rebolt();
-       }
+       core_flush_all_slbs(mm);
 }
 #endif /* CONFIG_PPC_64K_PAGES */
 
@@ -1191,22 +1187,6 @@ void hash_failure_debug(unsigned long ea, unsigned long access,
                trap, vsid, ssize, psize, lpsize, pte);
 }
 
-static void check_paca_psize(unsigned long ea, struct mm_struct *mm,
-                            int psize, bool user_region)
-{
-       if (user_region) {
-               if (psize != get_paca_psize(ea)) {
-                       copy_mm_to_paca(mm);
-                       slb_flush_and_rebolt();
-               }
-       } else if (get_paca()->vmalloc_sllp !=
-                  mmu_psize_defs[mmu_vmalloc_psize].sllp) {
-               get_paca()->vmalloc_sllp =
-                       mmu_psize_defs[mmu_vmalloc_psize].sllp;
-               slb_vmalloc_update();
-       }
-}
-
 /* Result code is:
  *  0 - handled
  *  1 - normal page fault
@@ -1239,7 +1219,7 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
                        rc = 1;
                        goto bail;
                }
-               psize = get_slice_psize(mm, ea);
+               psize = get_psize(mm, ea);
                ssize = user_segment_size(ea);
                vsid = get_user_vsid(&mm->context, ea, ssize);
                break;
@@ -1327,9 +1307,6 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
                        WARN_ON(1);
                }
 #endif
-               if (current->mm == mm)
-                       check_paca_psize(ea, mm, psize, user_region);
-
                goto bail;
        }
 
@@ -1364,15 +1341,14 @@ int hash_page_mm(struct mm_struct *mm, unsigned long ea,
                               "to 4kB pages because of "
                               "non-cacheable mapping\n");
                        psize = mmu_vmalloc_psize = MMU_PAGE_4K;
+                       slb_vmalloc_update();
                        copro_flush_all_slbs(mm);
+                       core_flush_all_slbs(mm);
                }
        }
 
 #endif /* CONFIG_PPC_64K_PAGES */
 
-       if (current->mm == mm)
-               check_paca_psize(ea, mm, psize, user_region);
-
 #ifdef CONFIG_PPC_64K_PAGES
        if (psize == MMU_PAGE_64K)
                rc = __hash_page_64K(ea, access, vsid, ptep, trap,
@@ -1460,7 +1436,7 @@ int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap,
 #ifdef CONFIG_PPC_MM_SLICES
 static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
 {
-       int psize = get_slice_psize(mm, ea);
+       int psize = get_psize(mm, ea);
 
        /* We only prefault standard pages for now */
        if (unlikely(psize != mm->context.user_psize))
index f84e14f23e50aa49ee76c12e81e52f91b40bb4a0..28ae2835db3d402bb648dde400676a2ed28c6570 100644 (file)
@@ -54,8 +54,7 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next,
                 * MMU context id, which is then moved to SPRN_PID.
                 *
                 * For the hash MMU it is either the first load from slb_cache
-                * in switch_slb(), and/or the store of paca->mm_ctx_id in
-                * copy_mm_to_paca().
+                * in switch_slb(), and/or load of MMU context id.
                 *
                 * On the other side, the barrier is in mm/tlb-radix.c for
                 * radix which orders earlier stores to clear the PTEs vs
index 6fec2ce3ccf4ada74640562662c3c344e7774114..1347ab86d32e86527c1f56d3d97f012d15208ce5 100644 (file)
@@ -347,8 +347,6 @@ void switch_slb(struct task_struct *tsk, struct mm_struct *mm)
                get_paca()->slb_cache_ptr = 0;
        }
 
-       copy_mm_to_paca(mm);
-
        /*
         * preload some userspace segments into the SLB.
         * Almost all 32 and 64bit PowerPC executables are linked at
@@ -375,6 +373,24 @@ void slb_set_size(u16 size)
        mmu_slb_size = size;
 }
 
+static void cpu_flush_slb(void *parm)
+{
+       struct mm_struct *mm = parm;
+       unsigned long flags;
+
+       if (mm != current->active_mm)
+               return;
+
+       local_irq_save(flags);
+       slb_flush_and_rebolt();
+       local_irq_restore(flags);
+}
+
+void core_flush_all_slbs(struct mm_struct *mm)
+{
+       on_each_cpu(cpu_flush_slb, mm, 1);
+}
+
 void slb_initialize(void)
 {
        unsigned long linear_llp, vmalloc_llp, io_llp;
index 205fe557ca109dda9a16e3fd9a8fe0f75909bc25..606f424aac4794cce120fc9579d90800ee020f9a 100644 (file)
@@ -207,23 +207,6 @@ static bool slice_check_range_fits(struct mm_struct *mm,
        return true;
 }
 
-static void slice_flush_segments(void *parm)
-{
-#ifdef CONFIG_PPC64
-       struct mm_struct *mm = parm;
-       unsigned long flags;
-
-       if (mm != current->active_mm)
-               return;
-
-       copy_mm_to_paca(current->active_mm);
-
-       local_irq_save(flags);
-       slb_flush_and_rebolt();
-       local_irq_restore(flags);
-#endif
-}
-
 static void slice_convert(struct mm_struct *mm,
                                const struct slice_mask *mask, int psize)
 {
@@ -289,6 +272,9 @@ static void slice_convert(struct mm_struct *mm,
        spin_unlock_irqrestore(&slice_convert_lock, flags);
 
        copro_flush_all_slbs(mm);
+#ifdef CONFIG_PPC64
+       core_flush_all_slbs(mm);
+#endif
 }
 
 /*
@@ -502,8 +488,9 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
                 * be already initialised beyond the old address limit.
                 */
                mm->context.slb_addr_limit = high_limit;
-
-               on_each_cpu(slice_flush_segments, mm, 1);
+#ifdef CONFIG_PPC64
+               core_flush_all_slbs(mm);
+#endif
        }
 
        /* Sanity checks */
@@ -665,8 +652,10 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
                (SLICE_NUM_HIGH &&
                 !bitmap_empty(potential_mask.high_slices, SLICE_NUM_HIGH))) {
                slice_convert(mm, &potential_mask, psize);
+#ifdef CONFIG_PPC64
                if (psize > MMU_PAGE_BASE)
-                       on_each_cpu(slice_flush_segments, mm, 1);
+                       core_flush_all_slbs(mm);
+#endif
        }
        return newaddr;