powerpc: Optimize hugepage invalidate

Hugepage invalidate involves invalidating multiple hpte entries.
Optimize the operation using H_BULK_REMOVE on lpar platforms.
On native, reduce the number of tlb flush.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 801e3c6..8b48090 100644 (file)
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -57,6 +57,9 @@ struct machdep_calls {
        void            (*hpte_removebolted)(unsigned long ea,
                                             int psize, int ssize);
        void            (*flush_hash_range)(unsigned long number, int local);
+       void            (*hugepage_invalidate)(struct mm_struct *mm,
+                                              unsigned char *hpte_slot_array,
+                                              unsigned long addr, int psize);
 
        /* special for kexec, to be called in real mode, linear mapping is
         * destroyed as well */

diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
index 6d152bc..3f0c30a 100644 (file)
--- a/arch/powerpc/mm/hash_native_64.c
+++ b/arch/powerpc/mm/hash_native_64.c
@@ -407,6 +407,78 @@ static void native_hpte_invalidate(unsigned long slot, unsigned long vpn,
        local_irq_restore(flags);
 }
 
+static void native_hugepage_invalidate(struct mm_struct *mm,
+                                      unsigned char *hpte_slot_array,
+                                      unsigned long addr, int psize)
+{
+       int ssize = 0, i;
+       int lock_tlbie;
+       struct hash_pte *hptep;
+       int actual_psize = MMU_PAGE_16M;
+       unsigned int max_hpte_count, valid;
+       unsigned long flags, s_addr = addr;
+       unsigned long hpte_v, want_v, shift;
+       unsigned long hidx, vpn = 0, vsid, hash, slot;
+
+       shift = mmu_psize_defs[psize].shift;
+       max_hpte_count = 1U << (PMD_SHIFT - shift);
+
+       local_irq_save(flags);
+       for (i = 0; i < max_hpte_count; i++) {
+               valid = hpte_valid(hpte_slot_array, i);
+               if (!valid)
+                       continue;
+               hidx =  hpte_hash_index(hpte_slot_array, i);
+
+               /* get the vpn */
+               addr = s_addr + (i * (1ul << shift));
+               if (!is_kernel_addr(addr)) {
+                       ssize = user_segment_size(addr);
+                       vsid = get_vsid(mm->context.id, addr, ssize);
+                       WARN_ON(vsid == 0);
+               } else {
+                       vsid = get_kernel_vsid(addr, mmu_kernel_ssize);
+                       ssize = mmu_kernel_ssize;
+               }
+
+               vpn = hpt_vpn(addr, vsid, ssize);
+               hash = hpt_hash(vpn, shift, ssize);
+               if (hidx & _PTEIDX_SECONDARY)
+                       hash = ~hash;
+
+               slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+               slot += hidx & _PTEIDX_GROUP_IX;
+
+               hptep = htab_address + slot;
+               want_v = hpte_encode_avpn(vpn, psize, ssize);
+               native_lock_hpte(hptep);
+               hpte_v = hptep->v;
+
+               /* Even if we miss, we need to invalidate the TLB */
+               if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))
+                       native_unlock_hpte(hptep);
+               else
+                       /* Invalidate the hpte. NOTE: this also unlocks it */
+                       hptep->v = 0;
+       }
+       /*
+        * Since this is a hugepage, we just need a single tlbie.
+        * use the last vpn.
+        */
+       lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
+       if (lock_tlbie)
+               raw_spin_lock(&native_tlbie_lock);
+
+       asm volatile("ptesync":::"memory");
+       __tlbie(vpn, psize, actual_psize, ssize);
+       asm volatile("eieio; tlbsync; ptesync":::"memory");
+
+       if (lock_tlbie)
+               raw_spin_unlock(&native_tlbie_lock);
+
+       local_irq_restore(flags);
+}
+
 static inline int __hpte_actual_psize(unsigned int lp, int psize)
 {
        int i, shift;
@@ -640,4 +712,5 @@ void __init hpte_init_native(void)
        ppc_md.hpte_remove      = native_hpte_remove;
        ppc_md.hpte_clear_all   = native_hpte_clear;
        ppc_md.flush_hash_range = native_flush_hash_range;
+       ppc_md.hugepage_invalidate   = native_hugepage_invalidate;
 }

diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 074a4a2..536eec7 100644 (file)
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -708,6 +708,7 @@ void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr,
 {
        int ssize, i;
        unsigned long s_addr;
+       int max_hpte_count;
        unsigned int psize, valid;
        unsigned char *hpte_slot_array;
        unsigned long hidx, vpn, vsid, hash, shift, slot;
@@ -727,9 +728,16 @@ void hpte_do_hugepage_flush(struct mm_struct *mm, unsigned long addr,
 
        /* get the base page size */
        psize = get_slice_psize(mm, s_addr);
-       shift = mmu_psize_defs[psize].shift;
 
-       for (i = 0; i < (HPAGE_PMD_SIZE >> shift); i++) {
+       if (ppc_md.hugepage_invalidate)
+               return ppc_md.hugepage_invalidate(mm, hpte_slot_array,
+                                                 s_addr, psize);
+       /*
+        * No bluk hpte removal support, invalidate each entry
+        */
+       shift = mmu_psize_defs[psize].shift;
+       max_hpte_count = HPAGE_PMD_SIZE >> shift;
+       for (i = 0; i < max_hpte_count; i++) {
                /*
                 * 8 bits per each hpte entries
                 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit]

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index ca45c8f..fd0f2f2 100644 (file)
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -45,6 +45,13 @@
 #include "plpar_wrappers.h"
 #include "pseries.h"
 
+/* Flag bits for H_BULK_REMOVE */
+#define HBR_REQUEST    0x4000000000000000UL
+#define HBR_RESPONSE   0x8000000000000000UL
+#define HBR_END                0xc000000000000000UL
+#define HBR_AVPN       0x0200000000000000UL
+#define HBR_ANDCOND    0x0100000000000000UL
+
 
 /* in hvCall.S */
 EXPORT_SYMBOL(plpar_hcall);
@@ -347,6 +354,113 @@ static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long vpn,
        BUG_ON(lpar_rc != H_SUCCESS);
 }
 
+/*
+ * Limit iterations holding pSeries_lpar_tlbie_lock to 3. We also need
+ * to make sure that we avoid bouncing the hypervisor tlbie lock.
+ */
+#define PPC64_HUGE_HPTE_BATCH 12
+
+static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
+                                            unsigned long *vpn, int count,
+                                            int psize, int ssize)
+{
+       unsigned long param[8];
+       int i = 0, pix = 0, rc;
+       unsigned long flags = 0;
+       int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
+
+       if (lock_tlbie)
+               spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
+
+       for (i = 0; i < count; i++) {
+
+               if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
+                       pSeries_lpar_hpte_invalidate(slot[i], vpn[i], psize, 0,
+                                                    ssize, 0);
+               } else {
+                       param[pix] = HBR_REQUEST | HBR_AVPN | slot[i];
+                       param[pix+1] = hpte_encode_avpn(vpn[i], psize, ssize);
+                       pix += 2;
+                       if (pix == 8) {
+                               rc = plpar_hcall9(H_BULK_REMOVE, param,
+                                                 param[0], param[1], param[2],
+                                                 param[3], param[4], param[5],
+                                                 param[6], param[7]);
+                               BUG_ON(rc != H_SUCCESS);
+                               pix = 0;
+                       }
+               }
+       }
+       if (pix) {
+               param[pix] = HBR_END;
+               rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
+                                 param[2], param[3], param[4], param[5],
+                                 param[6], param[7]);
+               BUG_ON(rc != H_SUCCESS);
+       }
+
+       if (lock_tlbie)
+               spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
+}
+
+static void pSeries_lpar_hugepage_invalidate(struct mm_struct *mm,
+                                      unsigned char *hpte_slot_array,
+                                      unsigned long addr, int psize)
+{
+       int ssize = 0, i, index = 0;
+       unsigned long s_addr = addr;
+       unsigned int max_hpte_count, valid;
+       unsigned long vpn_array[PPC64_HUGE_HPTE_BATCH];
+       unsigned long slot_array[PPC64_HUGE_HPTE_BATCH];
+       unsigned long shift, hidx, vpn = 0, vsid, hash, slot;
+
+       shift = mmu_psize_defs[psize].shift;
+       max_hpte_count = 1U << (PMD_SHIFT - shift);
+
+       for (i = 0; i < max_hpte_count; i++) {
+               valid = hpte_valid(hpte_slot_array, i);
+               if (!valid)
+                       continue;
+               hidx =  hpte_hash_index(hpte_slot_array, i);
+
+               /* get the vpn */
+               addr = s_addr + (i * (1ul << shift));
+               if (!is_kernel_addr(addr)) {
+                       ssize = user_segment_size(addr);
+                       vsid = get_vsid(mm->context.id, addr, ssize);
+                       WARN_ON(vsid == 0);
+               } else {
+                       vsid = get_kernel_vsid(addr, mmu_kernel_ssize);
+                       ssize = mmu_kernel_ssize;
+               }
+
+               vpn = hpt_vpn(addr, vsid, ssize);
+               hash = hpt_hash(vpn, shift, ssize);
+               if (hidx & _PTEIDX_SECONDARY)
+                       hash = ~hash;
+
+               slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+               slot += hidx & _PTEIDX_GROUP_IX;
+
+               slot_array[index] = slot;
+               vpn_array[index] = vpn;
+               if (index == PPC64_HUGE_HPTE_BATCH - 1) {
+                       /*
+                        * Now do a bluk invalidate
+                        */
+                       __pSeries_lpar_hugepage_invalidate(slot_array,
+                                                          vpn_array,
+                                                          PPC64_HUGE_HPTE_BATCH,
+                                                          psize, ssize);
+                       index = 0;
+               } else
+                       index++;
+       }
+       if (index)
+               __pSeries_lpar_hugepage_invalidate(slot_array, vpn_array,
+                                                  index, psize, ssize);
+}
+
 static void pSeries_lpar_hpte_removebolted(unsigned long ea,
                                           int psize, int ssize)
 {
@@ -364,13 +478,6 @@ static void pSeries_lpar_hpte_removebolted(unsigned long ea,
        pSeries_lpar_hpte_invalidate(slot, vpn, psize, 0, ssize, 0);
 }
 
-/* Flag bits for H_BULK_REMOVE */
-#define HBR_REQUEST    0x4000000000000000UL
-#define HBR_RESPONSE   0x8000000000000000UL
-#define HBR_END                0xc000000000000000UL
-#define HBR_AVPN       0x0200000000000000UL
-#define HBR_ANDCOND    0x0100000000000000UL
-
 /*
  * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
  * lock.
@@ -459,6 +566,7 @@ void __init hpte_init_lpar(void)
        ppc_md.hpte_removebolted = pSeries_lpar_hpte_removebolted;
        ppc_md.flush_hash_range = pSeries_lpar_flush_hash_range;
        ppc_md.hpte_clear_all   = pSeries_lpar_hptab_clear;
+       ppc_md.hugepage_invalidate = pSeries_lpar_hugepage_invalidate;
 }
 
 #ifdef CONFIG_PPC_SMLPAR