From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
To: npiggin@gmail.com, benh@kernel.crashing.org, paulus@samba.org,
mpe@ellerman.id.au
Cc: linuxppc-dev@lists.ozlabs.org,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: [PATCH 1/3] powerpc/mm/hash: Remove the superfluous bitwise operation when find hpte group
Date: Fri, 29 Jun 2018 14:06:29 +0530 [thread overview]
Message-ID: <20180629083631.28017-1-aneesh.kumar@linux.ibm.com> (raw)
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
When computing the starting slot number for a hash page table group we used
to do this
hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
Multiplying with 8 (HPTES_PER_GROUP) imply the last three bits are 0. Hence we
really don't need to clear then separately.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
arch/powerpc/mm/dump_hashpagetable.c | 2 +-
arch/powerpc/mm/hash64_4k.c | 8 ++++----
arch/powerpc/mm/hash64_64k.c | 15 +++++++--------
arch/powerpc/mm/hash_utils_64.c | 10 ++++------
arch/powerpc/mm/hugepage-hash64.c | 9 ++++-----
5 files changed, 20 insertions(+), 24 deletions(-)
diff --git a/arch/powerpc/mm/dump_hashpagetable.c b/arch/powerpc/mm/dump_hashpagetable.c
index 14cfb11b09d0..d241cb6518da 100644
--- a/arch/powerpc/mm/dump_hashpagetable.c
+++ b/arch/powerpc/mm/dump_hashpagetable.c
@@ -260,7 +260,7 @@ static int pseries_find(unsigned long ea, int psize, bool primary, u64 *v, u64 *
/* to check in the secondary hash table, we invert the hash */
if (!primary)
hash = ~hash;
- hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* see if we can find an entry in the hpte with this hash */
for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) {
lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes);
diff --git a/arch/powerpc/mm/hash64_4k.c b/arch/powerpc/mm/hash64_4k.c
index d573d7d07f25..6fa6765a10eb 100644
--- a/arch/powerpc/mm/hash64_4k.c
+++ b/arch/powerpc/mm/hash64_4k.c
@@ -80,7 +80,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
hash = hpt_hash(vpn, shift, ssize);
repeat:
- hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0,
@@ -89,7 +89,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* Primary is full, try the secondary
*/
if (unlikely(slot == -1)) {
- hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
rflags,
HPTE_V_SECONDARY,
@@ -97,8 +97,8 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
MMU_PAGE_4K, ssize);
if (slot == -1) {
if (mftb() & 0x1)
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) *
+ HPTES_PER_GROUP;
mmu_hash_ops.hpte_remove(hpte_group);
/*
* FIXME!! Should be try the group from which we removed ?
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index e601d95c3b20..3afa253d7f52 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -154,7 +154,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
}
hash = hpt_hash(vpn, shift, ssize);
repeat:
- hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0,
@@ -165,7 +165,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
if (unlikely(slot == -1)) {
bool soft_invalid;
- hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
rflags, HPTE_V_SECONDARY,
MMU_PAGE_4K, MMU_PAGE_4K,
@@ -193,8 +193,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* that we do not get the same soft-invalid slot.
*/
if (soft_invalid || (mftb() & 0x1))
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
mmu_hash_ops.hpte_remove(hpte_group);
/*
@@ -288,7 +287,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
hash = hpt_hash(vpn, shift, ssize);
repeat:
- hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0,
@@ -298,7 +297,7 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
* Primary is full, try the secondary
*/
if (unlikely(slot == -1)) {
- hpte_group = ((~hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
rflags,
HPTE_V_SECONDARY,
@@ -306,8 +305,8 @@ int __hash_page_64K(unsigned long ea, unsigned long access,
MMU_PAGE_64K, ssize);
if (slot == -1) {
if (mftb() & 0x1)
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) *
+ HPTES_PER_GROUP;
mmu_hash_ops.hpte_remove(hpte_group);
/*
* FIXME!! Should be try the group from which we removed ?
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 8318716e5075..4ba901223000 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1783,8 +1783,7 @@ long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
long slot;
repeat:
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, vflags,
@@ -1792,15 +1791,14 @@ long hpte_insert_repeating(unsigned long hash, unsigned long vpn,
/* Primary is full, try the secondary */
if (unlikely(slot == -1)) {
- hpte_group = ((~hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags,
vflags | HPTE_V_SECONDARY,
psize, psize, ssize);
if (slot == -1) {
if (mftb() & 0x1)
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP)&~0x7UL;
+ hpte_group = (hash & htab_hash_mask) *
+ HPTES_PER_GROUP;
mmu_hash_ops.hpte_remove(hpte_group);
goto repeat;
diff --git a/arch/powerpc/mm/hugepage-hash64.c b/arch/powerpc/mm/hugepage-hash64.c
index f20d16f849c5..01f213d2bcb9 100644
--- a/arch/powerpc/mm/hugepage-hash64.c
+++ b/arch/powerpc/mm/hugepage-hash64.c
@@ -128,7 +128,7 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
new_pmd |= H_PAGE_HASHPTE;
repeat:
- hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
/* Insert into the hash table, primary slot */
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa, rflags, 0,
@@ -137,16 +137,15 @@ int __hash_page_thp(unsigned long ea, unsigned long access, unsigned long vsid,
* Primary is full, try the secondary
*/
if (unlikely(slot == -1)) {
- hpte_group = ((~hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
slot = mmu_hash_ops.hpte_insert(hpte_group, vpn, pa,
rflags,
HPTE_V_SECONDARY,
psize, lpsize, ssize);
if (slot == -1) {
if (mftb() & 0x1)
- hpte_group = ((hash & htab_hash_mask) *
- HPTES_PER_GROUP) & ~0x7UL;
+ hpte_group = (hash & htab_hash_mask) *
+ HPTES_PER_GROUP;
mmu_hash_ops.hpte_remove(hpte_group);
goto repeat;
--
2.17.1
next reply other threads:[~2018-06-29 8:36 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-29 8:36 Aneesh Kumar K.V [this message]
2018-06-29 8:36 ` [PATCH 2/3] powerpc/mm/hash: Add hpte_get_old_v and use that instead of opencoding Aneesh Kumar K.V
2018-06-29 8:36 ` [PATCH 3/3] powerpc/mm/nv/hash: Reduce contention on hpte lock Aneesh Kumar K.V
2018-07-24 13:59 ` [1/3] powerpc/mm/hash: Remove the superfluous bitwise operation when find hpte group Michael Ellerman
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