powerpc/mm: Use H_READ with H_READ_4

This will bulk read 4 hash pte slot entries and should reduce the loop

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/plpar_wrappers.h b/arch/powerpc/include/asm/plpar_wrappers.h
index 67859edbf8fd39aba27c8f8b7503533d6d9a3271..1b394247afc2dc86c76a26c9b5ed0274ae0de536 100644 (file)
--- a/arch/powerpc/include/asm/plpar_wrappers.h
+++ b/arch/powerpc/include/asm/plpar_wrappers.h
@@ -201,6 +201,23 @@ static inline long plpar_pte_read_raw(unsigned long flags, unsigned long ptex,
        return rc;
 }
 
+/*
+ * ptes must be 8*sizeof(unsigned long)
+ */
+static inline long plpar_pte_read_4(unsigned long flags, unsigned long ptex,
+                                   unsigned long *ptes)
+
+{
+       long rc;
+       unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
+
+       rc = plpar_hcall9(H_READ, retbuf, flags | H_READ_4, ptex);
+
+       memcpy(ptes, retbuf, 8*sizeof(unsigned long));
+
+       return rc;
+}
+
 /*
  * plpar_pte_read_4_raw can be called in real mode.
  * ptes must be 8*sizeof(unsigned long)

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 6d46547871aaa675949fdbe60d96cbd69aad2c76..477290ad855e50a5f0c5da5065ba4b174b77fcfa 100644 (file)
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -315,48 +315,48 @@ static long pSeries_lpar_hpte_updatepp(unsigned long slot,
        return 0;
 }
 
-static unsigned long pSeries_lpar_hpte_getword0(unsigned long slot)
+static long __pSeries_lpar_hpte_find(unsigned long want_v, unsigned long hpte_group)
 {
-       unsigned long dword0;
-       unsigned long lpar_rc;
-       unsigned long dummy_word1;
-       unsigned long flags;
+       long lpar_rc;
+       unsigned long i, j;
+       struct {
+               unsigned long pteh;
+               unsigned long ptel;
+       } ptes[4];
 
-       /* Read 1 pte at a time                        */
-       /* Do not need RPN to logical page translation */
-       /* No cross CEC PFT access                     */
-       flags = 0;
+       for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) {
 
-       lpar_rc = plpar_pte_read(flags, slot, &dword0, &dummy_word1);
+               lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes);
+               if (lpar_rc != H_SUCCESS)
+                       continue;
 
-       BUG_ON(lpar_rc != H_SUCCESS);
+               for (j = 0; j < 4; j++) {
+                       if (HPTE_V_COMPARE(ptes[j].pteh, want_v) &&
+                           (ptes[j].pteh & HPTE_V_VALID))
+                               return i + j;
+               }
+       }
 
-       return dword0;
+       return -1;
 }
 
 static long pSeries_lpar_hpte_find(unsigned long vpn, int psize, int ssize)
 {
-       unsigned long hash;
-       unsigned long i;
        long slot;
-       unsigned long want_v, hpte_v;
+       unsigned long hash;
+       unsigned long want_v;
+       unsigned long hpte_group;
 
        hash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);
        want_v = hpte_encode_avpn(vpn, psize, ssize);
 
        /* Bolted entries are always in the primary group */
-       slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
-       for (i = 0; i < HPTES_PER_GROUP; i++) {
-               hpte_v = pSeries_lpar_hpte_getword0(slot);
-
-               if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
-                       /* HPTE matches */
-                       return slot;
-               ++slot;
-       }
-
-       return -1;
-} 
+       hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+       slot = __pSeries_lpar_hpte_find(want_v, hpte_group);
+       if (slot < 0)
+               return -1;
+       return hpte_group + slot;
+}
 
 static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
                                             unsigned long ea,