* [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 01/11] arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present Punit Agrawal
` (10 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
Hi,
This patchset addresses all the known issues with contiguous hugetlb
pages. Support for contiguous hugepages is useful on systems where the
PMD hugepage size is too large (512MB hugepage when using 64k page
granule).
The patches can be split as
* Patches 1-5, 11 cleanups and improvements
* Patch 6 addresses the break-before-make requirement of the
architecture for contiguous hugepages. These patches depend on
enabling memory failure handling on arm64[2].
* Patch 7-9 add support for handling swap entries for contiguous pte
hugepages. These patches depend on fixes to core code required to
support contiguous hugepages[3].
* Patch 10 enables contiguous hugepage support for arm64
The patches are based on v4.12-rc2. Previous postings can be found at
[0], [1].
All feedback welcome.
Thanks,
Punit
[0] https://www.spinics.net/lists/arm-kernel/msg570422.html
[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2017-March/497027.html
[2] https://www.spinics.net/lists/arm-kernel/msg581657.html
[3] https://www.spinics.net/lists/arm-kernel/msg582682.html
Changes v2 -> v3
* Rebased on v4.12-rc2
* Included swap related fixes in this series
* Enable contiguous pte hugepages
Changes v1 -> v2:
* Marked patch 2 for stable
* Fixed comment issues in patch 7
* Added tags
Punit Agrawal (4):
arm64: hugetlbpages: Handle swap entries in huge_pte_offset() for
contiguous hugepages
arm64: hugetlb: Override huge_pte_clear() to support contiguous
hugepages
arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous
hugepages
arm64: Re-enable support for contiguous hugepages
Steve Capper (7):
arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present
arm64: hugetlb: Refactor find_num_contig
arm64: hugetlb: Introduce pte_pgprot helper
arm64: hugetlb: Remove spurious calls to huge_ptep_offset
arm64: hugetlb: Spring clean huge pte accessors
arm64: hugetlb: Add break-before-make logic for contiguous entries
arm64: hugetlb: Cleanup setup_hugepagesz
arch/arm64/mm/hugetlbpage.c | 305 ++++++++++++++++++++++++++++++--------------
1 file changed, 209 insertions(+), 96 deletions(-)
--
2.11.0
^ permalink raw reply [flat|nested] 15+ messages in thread* [PATCH v3 01/11] arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
2017-05-22 14:39 ` Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 02/11] arm64: hugetlb: Refactor find_num_contig Punit Agrawal
` (9 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
This patch adds a WARN_ON to set_huge_pte_at as the accessor assumes
that entries to be written down are all present. (There are separate
accessors to clear huge ptes).
We will need to handle the !pte_present case where memory offlining
is used on hugetlb pages. swap and migration entries will be supplied
to set_huge_pte_at in this case.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 425a8fcd3d38..0389e2ed51f1 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -69,6 +69,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
unsigned long pfn;
pgprot_t hugeprot;
+ /*
+ * Code needs to be expanded to handle huge swap and migration
+ * entries. Needed for HUGETLB and MEMORY_FAILURE.
+ */
+ WARN_ON(!pte_present(pte));
+
if (ncontig == 1) {
set_pte_at(mm, addr, ptep, pte);
return;
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 02/11] arm64: hugetlb: Refactor find_num_contig
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 01/11] arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 03/11] arm64: hugetlb: Introduce pte_pgprot helper Punit Agrawal
` (8 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
As we regularly check for contiguous pte's in the huge accessors, remove
this extra check from find_num_contig.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 0389e2ed51f1..804710dd7463 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -42,15 +42,13 @@ int pud_huge(pud_t pud)
}
static int find_num_contig(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte, size_t *pgsize)
+ pte_t *ptep, size_t *pgsize)
{
pgd_t *pgd = pgd_offset(mm, addr);
pud_t *pud;
pmd_t *pmd;
*pgsize = PAGE_SIZE;
- if (!pte_cont(pte))
- return 1;
pud = pud_offset(pgd, addr);
pmd = pmd_offset(pud, addr);
if ((pte_t *)pmd == ptep) {
@@ -65,7 +63,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
{
size_t pgsize;
int i;
- int ncontig = find_num_contig(mm, addr, ptep, pte, &pgsize);
+ int ncontig;
unsigned long pfn;
pgprot_t hugeprot;
@@ -75,11 +73,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
*/
WARN_ON(!pte_present(pte));
- if (ncontig == 1) {
+ if (!pte_cont(pte)) {
set_pte_at(mm, addr, ptep, pte);
return;
}
+ ncontig = find_num_contig(mm, addr, ptep, &pgsize);
pfn = pte_pfn(pte);
hugeprot = __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
for (i = 0; i < ncontig; i++) {
@@ -195,7 +194,7 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
bool is_dirty = false;
cpte = huge_pte_offset(mm, addr);
- ncontig = find_num_contig(mm, addr, cpte, *cpte, &pgsize);
+ ncontig = find_num_contig(mm, addr, cpte, &pgsize);
/* save the 1st pte to return */
pte = ptep_get_and_clear(mm, addr, cpte);
for (i = 1, addr += pgsize; i < ncontig; ++i, addr += pgsize) {
@@ -235,7 +234,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
cpte = huge_pte_offset(vma->vm_mm, addr);
pfn = pte_pfn(*cpte);
ncontig = find_num_contig(vma->vm_mm, addr, cpte,
- *cpte, &pgsize);
+ &pgsize);
for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize) {
changed |= ptep_set_access_flags(vma, addr, cpte,
pfn_pte(pfn,
@@ -258,7 +257,7 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
size_t pgsize = 0;
cpte = huge_pte_offset(mm, addr);
- ncontig = find_num_contig(mm, addr, cpte, *cpte, &pgsize);
+ ncontig = find_num_contig(mm, addr, cpte, &pgsize);
for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize)
ptep_set_wrprotect(mm, addr, cpte);
} else {
@@ -276,7 +275,7 @@ void huge_ptep_clear_flush(struct vm_area_struct *vma,
cpte = huge_pte_offset(vma->vm_mm, addr);
ncontig = find_num_contig(vma->vm_mm, addr, cpte,
- *cpte, &pgsize);
+ &pgsize);
for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize)
ptep_clear_flush(vma, addr, cpte);
} else {
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 03/11] arm64: hugetlb: Introduce pte_pgprot helper
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (2 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 02/11] arm64: hugetlb: Refactor find_num_contig Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 04/11] arm64: hugetlb: Remove spurious calls to huge_ptep_offset Punit Agrawal
` (7 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
Rather than xor pte bits in various places, use this helper function.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 804710dd7463..3058ec0fcedd 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -41,6 +41,16 @@ int pud_huge(pud_t pud)
#endif
}
+/*
+ * Select all bits except the pfn
+ */
+static inline pgprot_t pte_pgprot(pte_t pte)
+{
+ unsigned long pfn = pte_pfn(pte);
+
+ return __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
+}
+
static int find_num_contig(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, size_t *pgsize)
{
@@ -80,7 +90,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
pfn = pte_pfn(pte);
- hugeprot = __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^ pte_val(pte));
+ hugeprot = pte_pgprot(pte);
for (i = 0; i < ncontig; i++) {
pr_debug("%s: set pte %p to 0x%llx\n", __func__, ptep,
pte_val(pfn_pte(pfn, hugeprot)));
@@ -227,9 +237,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
size_t pgsize = 0;
unsigned long pfn = pte_pfn(pte);
/* Select all bits except the pfn */
- pgprot_t hugeprot =
- __pgprot(pte_val(pfn_pte(pfn, __pgprot(0))) ^
- pte_val(pte));
+ pgprot_t hugeprot = pte_pgprot(pte);
cpte = huge_pte_offset(vma->vm_mm, addr);
pfn = pte_pfn(*cpte);
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 04/11] arm64: hugetlb: Remove spurious calls to huge_ptep_offset
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (3 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 03/11] arm64: hugetlb: Introduce pte_pgprot helper Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 05/11] arm64: hugetlb: Spring clean huge pte accessors Punit Agrawal
` (6 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
We don't need to call huge_ptep_offset as our accessors are already
supplied with the pte_t *. This patch removes those spurious calls.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 37 ++++++++++++++-----------------------
1 file changed, 14 insertions(+), 23 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 3058ec0fcedd..cb84ca33bc6b 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -200,21 +200,19 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
if (pte_cont(*ptep)) {
int ncontig, i;
size_t pgsize;
- pte_t *cpte;
bool is_dirty = false;
- cpte = huge_pte_offset(mm, addr);
- ncontig = find_num_contig(mm, addr, cpte, &pgsize);
+ ncontig = find_num_contig(mm, addr, ptep, &pgsize);
/* save the 1st pte to return */
- pte = ptep_get_and_clear(mm, addr, cpte);
+ pte = ptep_get_and_clear(mm, addr, ptep);
for (i = 1, addr += pgsize; i < ncontig; ++i, addr += pgsize) {
/*
* If HW_AFDBM is enabled, then the HW could
* turn on the dirty bit for any of the page
* in the set, so check them all.
*/
- ++cpte;
- if (pte_dirty(ptep_get_and_clear(mm, addr, cpte)))
+ ++ptep;
+ if (pte_dirty(ptep_get_and_clear(mm, addr, ptep)))
is_dirty = true;
}
if (is_dirty)
@@ -230,8 +228,6 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t pte, int dirty)
{
- pte_t *cpte;
-
if (pte_cont(pte)) {
int ncontig, i, changed = 0;
size_t pgsize = 0;
@@ -239,12 +235,11 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
/* Select all bits except the pfn */
pgprot_t hugeprot = pte_pgprot(pte);
- cpte = huge_pte_offset(vma->vm_mm, addr);
- pfn = pte_pfn(*cpte);
- ncontig = find_num_contig(vma->vm_mm, addr, cpte,
+ pfn = pte_pfn(pte);
+ ncontig = find_num_contig(vma->vm_mm, addr, ptep,
&pgsize);
- for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize) {
- changed |= ptep_set_access_flags(vma, addr, cpte,
+ for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize) {
+ changed |= ptep_set_access_flags(vma, addr, ptep,
pfn_pte(pfn,
hugeprot),
dirty);
@@ -261,13 +256,11 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
{
if (pte_cont(*ptep)) {
int ncontig, i;
- pte_t *cpte;
size_t pgsize = 0;
- cpte = huge_pte_offset(mm, addr);
- ncontig = find_num_contig(mm, addr, cpte, &pgsize);
- for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize)
- ptep_set_wrprotect(mm, addr, cpte);
+ ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+ for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize)
+ ptep_set_wrprotect(mm, addr, ptep);
} else {
ptep_set_wrprotect(mm, addr, ptep);
}
@@ -278,14 +271,12 @@ void huge_ptep_clear_flush(struct vm_area_struct *vma,
{
if (pte_cont(*ptep)) {
int ncontig, i;
- pte_t *cpte;
size_t pgsize = 0;
- cpte = huge_pte_offset(vma->vm_mm, addr);
- ncontig = find_num_contig(vma->vm_mm, addr, cpte,
+ ncontig = find_num_contig(vma->vm_mm, addr, ptep,
&pgsize);
- for (i = 0; i < ncontig; ++i, ++cpte, addr += pgsize)
- ptep_clear_flush(vma, addr, cpte);
+ for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize)
+ ptep_clear_flush(vma, addr, ptep);
} else {
ptep_clear_flush(vma, addr, ptep);
}
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 05/11] arm64: hugetlb: Spring clean huge pte accessors
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (4 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 04/11] arm64: hugetlb: Remove spurious calls to huge_ptep_offset Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 06/11] arm64: hugetlb: Add break-before-make logic for contiguous entries Punit Agrawal
` (5 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
This patch aims to re-structure the huge pte accessors without affecting
their functionality. Control flow is changed to reduce indentation and
expanded use is made of post for loop variable modification.
It is then much easier to add break-before-make semantics in a subsequent
patch.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 119 ++++++++++++++++++++------------------------
1 file changed, 54 insertions(+), 65 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index cb84ca33bc6b..08deed7c71f0 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -74,7 +74,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
size_t pgsize;
int i;
int ncontig;
- unsigned long pfn;
+ unsigned long pfn, dpfn;
pgprot_t hugeprot;
/*
@@ -90,14 +90,13 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
pfn = pte_pfn(pte);
+ dpfn = pgsize >> PAGE_SHIFT;
hugeprot = pte_pgprot(pte);
- for (i = 0; i < ncontig; i++) {
+
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) {
pr_debug("%s: set pte %p to 0x%llx\n", __func__, ptep,
pte_val(pfn_pte(pfn, hugeprot)));
set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
- ptep++;
- pfn += pgsize >> PAGE_SHIFT;
- addr += pgsize;
}
}
@@ -195,91 +194,81 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- pte_t pte;
-
- if (pte_cont(*ptep)) {
- int ncontig, i;
- size_t pgsize;
- bool is_dirty = false;
-
- ncontig = find_num_contig(mm, addr, ptep, &pgsize);
- /* save the 1st pte to return */
- pte = ptep_get_and_clear(mm, addr, ptep);
- for (i = 1, addr += pgsize; i < ncontig; ++i, addr += pgsize) {
- /*
- * If HW_AFDBM is enabled, then the HW could
- * turn on the dirty bit for any of the page
- * in the set, so check them all.
- */
- ++ptep;
- if (pte_dirty(ptep_get_and_clear(mm, addr, ptep)))
- is_dirty = true;
- }
- if (is_dirty)
- return pte_mkdirty(pte);
- else
- return pte;
- } else {
+ int ncontig, i;
+ size_t pgsize;
+ pte_t orig_pte = huge_ptep_get(ptep);
+
+ if (!pte_cont(orig_pte))
return ptep_get_and_clear(mm, addr, ptep);
+
+ ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+ for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
+ /*
+ * If HW_AFDBM is enabled, then the HW could
+ * turn on the dirty bit for any of the page
+ * in the set, so check them all.
+ */
+ if (pte_dirty(ptep_get_and_clear(mm, addr, ptep)))
+ orig_pte = pte_mkdirty(orig_pte);
}
+
+ return orig_pte;
}
int huge_ptep_set_access_flags(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep,
pte_t pte, int dirty)
{
- if (pte_cont(pte)) {
- int ncontig, i, changed = 0;
- size_t pgsize = 0;
- unsigned long pfn = pte_pfn(pte);
- /* Select all bits except the pfn */
- pgprot_t hugeprot = pte_pgprot(pte);
-
- pfn = pte_pfn(pte);
- ncontig = find_num_contig(vma->vm_mm, addr, ptep,
- &pgsize);
- for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize) {
- changed |= ptep_set_access_flags(vma, addr, ptep,
- pfn_pte(pfn,
- hugeprot),
- dirty);
- pfn += pgsize >> PAGE_SHIFT;
- }
- return changed;
- } else {
+ int ncontig, i, changed = 0;
+ size_t pgsize = 0;
+ unsigned long pfn = pte_pfn(pte), dpfn;
+ pgprot_t hugeprot;
+
+ if (!pte_cont(pte))
return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+
+ ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
+ dpfn = pgsize >> PAGE_SHIFT;
+ hugeprot = pte_pgprot(pte);
+
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) {
+ changed |= ptep_set_access_flags(vma, addr, ptep,
+ pfn_pte(pfn, hugeprot), dirty);
}
+
+ return changed;
}
void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- if (pte_cont(*ptep)) {
- int ncontig, i;
- size_t pgsize = 0;
+ int ncontig, i;
+ size_t pgsize;
- ncontig = find_num_contig(mm, addr, ptep, &pgsize);
- for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize)
- ptep_set_wrprotect(mm, addr, ptep);
- } else {
+ if (!pte_cont(*ptep)) {
ptep_set_wrprotect(mm, addr, ptep);
+ return;
}
+
+ ncontig = find_num_contig(mm, addr, ptep, &pgsize);
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
+ ptep_set_wrprotect(mm, addr, ptep);
}
void huge_ptep_clear_flush(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
- if (pte_cont(*ptep)) {
- int ncontig, i;
- size_t pgsize = 0;
-
- ncontig = find_num_contig(vma->vm_mm, addr, ptep,
- &pgsize);
- for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize)
- ptep_clear_flush(vma, addr, ptep);
- } else {
+ int ncontig, i;
+ size_t pgsize;
+
+ if (!pte_cont(*ptep)) {
ptep_clear_flush(vma, addr, ptep);
+ return;
}
+
+ ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
+ ptep_clear_flush(vma, addr, ptep);
}
static __init int setup_hugepagesz(char *opt)
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 06/11] arm64: hugetlb: Add break-before-make logic for contiguous entries
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (5 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 05/11] arm64: hugetlb: Spring clean huge pte accessors Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 07/11] arm64: hugetlbpages: Handle swap entries in huge_pte_offset() for contiguous hugepages Punit Agrawal
` (4 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
It has become apparent that one has to take special care when modifying
attributes of memory mappings that employ the contiguous bit.
Both the requirement and the architecturally correct "Break-Before-Make"
technique of updating contiguous entries can be found described in:
ARM DDI 0487A.k_iss10775, "Misprogramming of the Contiguous bit",
page D4-1762.
The huge pte accessors currently replace the attributes of contiguous
pte entries in place thus can, on certain platforms, lead to TLB
conflict aborts or even erroneous results returned from TLB lookups.
This patch adds a helper function get_clear_flush(.) that clears a
contiguous entry and returns the head pte (whilst taking care to
retain dirty bit information that could have been modified by DBM).
A tlb invalidate is performed to then ensure that there is no
possibility of multiple tlb entries being present for the same
region.
Cc: David Woods <dwoods@mellanox.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
(Fixed indentation and some comments cleanup)
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 81 +++++++++++++++++++++++++++++++++++----------
1 file changed, 64 insertions(+), 17 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 08deed7c71f0..f2c976464f39 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -68,6 +68,47 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr,
return CONT_PTES;
}
+/*
+ * Changing some bits of contiguous entries requires us to follow a
+ * Break-Before-Make approach, breaking the whole contiguous set
+ * before we can change any entries. See ARM DDI 0487A.k_iss10775,
+ * "Misprogramming of the Contiguous bit", page D4-1762.
+ *
+ * This helper performs the break step.
+ */
+static pte_t get_clear_flush(struct mm_struct *mm,
+ unsigned long addr,
+ pte_t *ptep,
+ unsigned long pgsize,
+ unsigned long ncontig)
+{
+ unsigned long i, saddr = addr;
+ struct vm_area_struct vma = { .vm_mm = mm };
+ pte_t orig_pte = huge_ptep_get(ptep);
+
+ /*
+ * If we already have a faulting entry then we don't need
+ * to break before make (there won't be a tlb entry cached).
+ */
+ if (!pte_present(orig_pte))
+ return orig_pte;
+
+ for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
+ pte_t pte = ptep_get_and_clear(mm, addr, ptep);
+
+ /*
+ * If HW_AFDBM is enabled, then the HW could turn on
+ * the dirty bit for any page in the set, so check
+ * them all. All hugetlb entries are already young.
+ */
+ if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) && pte_dirty(pte))
+ orig_pte = pte_mkdirty(orig_pte);
+ }
+
+ flush_tlb_range(&vma, saddr, addr);
+ return orig_pte;
+}
+
void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte)
{
@@ -93,6 +134,8 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
dpfn = pgsize >> PAGE_SHIFT;
hugeprot = pte_pgprot(pte);
+ get_clear_flush(mm, addr, ptep, pgsize, ncontig);
+
for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) {
pr_debug("%s: set pte %p to 0x%llx\n", __func__, ptep,
pte_val(pfn_pte(pfn, hugeprot)));
@@ -194,7 +237,7 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
- int ncontig, i;
+ int ncontig;
size_t pgsize;
pte_t orig_pte = huge_ptep_get(ptep);
@@ -202,17 +245,8 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
return ptep_get_and_clear(mm, addr, ptep);
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
- for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
- /*
- * If HW_AFDBM is enabled, then the HW could
- * turn on the dirty bit for any of the page
- * in the set, so check them all.
- */
- if (pte_dirty(ptep_get_and_clear(mm, addr, ptep)))
- orig_pte = pte_mkdirty(orig_pte);
- }
- return orig_pte;
+ return get_clear_flush(mm, addr, ptep, pgsize, ncontig);
}
int huge_ptep_set_access_flags(struct vm_area_struct *vma,
@@ -222,6 +256,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
int ncontig, i, changed = 0;
size_t pgsize = 0;
unsigned long pfn = pte_pfn(pte), dpfn;
+ pte_t orig_pte;
pgprot_t hugeprot;
if (!pte_cont(pte))
@@ -231,10 +266,12 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
dpfn = pgsize >> PAGE_SHIFT;
hugeprot = pte_pgprot(pte);
- for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) {
- changed |= ptep_set_access_flags(vma, addr, ptep,
- pfn_pte(pfn, hugeprot), dirty);
- }
+ orig_pte = get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ if (!pte_same(orig_pte, pte))
+ changed = 1;
+
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
+ set_pte_at(vma->vm_mm, addr, ptep, pfn_pte(pfn, hugeprot));
return changed;
}
@@ -244,6 +281,9 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
{
int ncontig, i;
size_t pgsize;
+ pte_t pte = pte_wrprotect(huge_ptep_get(ptep)), orig_pte;
+ unsigned long pfn = pte_pfn(pte), dpfn;
+ pgprot_t hugeprot;
if (!pte_cont(*ptep)) {
ptep_set_wrprotect(mm, addr, ptep);
@@ -251,8 +291,15 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
}
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
- for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
- ptep_set_wrprotect(mm, addr, ptep);
+ dpfn = pgsize >> PAGE_SHIFT;
+
+ orig_pte = get_clear_flush(mm, addr, ptep, pgsize, ncontig);
+ if (pte_dirty(orig_pte))
+ pte = pte_mkdirty(pte);
+
+ hugeprot = pte_pgprot(pte);
+ for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
+ set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
}
void huge_ptep_clear_flush(struct vm_area_struct *vma,
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 07/11] arm64: hugetlbpages: Handle swap entries in huge_pte_offset() for contiguous hugepages
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (6 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 06/11] arm64: hugetlb: Add break-before-make logic for contiguous entries Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 08/11] arm64: hugetlb: Override huge_pte_clear() to support " Punit Agrawal
` (3 subsequent siblings)
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
huge_pte_offset() was updated to correctly handle swap entries for
hugepages. With the addition of the size parameter, it is now possible
to disambiguate whether the request is for a regular hugepage or a
contiguous hugepage.
Fix huge_pte_offset() for contiguous hugepages by using the size to find
the correct page table entry.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: David Woods <dwoods@mellanox.com>
---
arch/arm64/mm/hugetlbpage.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index f2c976464f39..e9061704aec3 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -195,6 +195,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
+ pte_t *pte;
pgd = pgd_offset(mm, addr);
pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd);
@@ -202,19 +203,29 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
return NULL;
pud = pud_offset(pgd, addr);
- if (pud_none(*pud))
+ if (pud_none(*pud) && sz != PUD_SIZE)
return NULL;
/* swap or huge page */
if (!pud_present(*pud) || pud_huge(*pud))
return (pte_t *)pud;
/* table; check the next level */
+ if (sz == CONT_PMD_SIZE)
+ addr &= CONT_PMD_MASK;
+
pmd = pmd_offset(pud, addr);
- if (pmd_none(*pmd))
+ if (pmd_none(*pmd) &&
+ !(sz == PMD_SIZE || sz == CONT_PMD_SIZE))
return NULL;
if (!pmd_present(*pmd) || pmd_huge(*pmd))
return (pte_t *)pmd;
+ if (sz == CONT_PTE_SIZE) {
+ pte = pte_offset_kernel(
+ pmd, (addr & CONT_PTE_MASK));
+ return pte;
+ }
+
return NULL;
}
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 08/11] arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (7 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 07/11] arm64: hugetlbpages: Handle swap entries in huge_pte_offset() for contiguous hugepages Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 16:45 ` [PATCH v3.1 8/11] " Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 09/11] arm64: hugetlb: Override set_huge_swap_pte_at() " Punit Agrawal
` (2 subsequent siblings)
11 siblings, 1 reply; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
The default huge_pte_clear() implementation does not clear contiguous
page table entries when it encounters contiguous hugepages that are
supported on arm64.
Fix this by overriding the default implementation to clear all the
entries associated with contiguous hugepages.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: David Woods <dwoods@mellanox.com>
---
arch/arm64/mm/hugetlbpage.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index e9061704aec3..240b2fd53266 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -68,6 +68,30 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr,
return CONT_PTES;
}
+static inline int num_contig_ptes(unsigned long size, size_t *pgsize)
+{
+ int contig_ptes = 0;
+
+ *pgsize = size;
+
+ switch (size) {
+ case PUD_SIZE:
+ case PMD_SIZE:
+ contig_ptes = 1;
+ break;
+ case CONT_PMD_SIZE:
+ *pgsize = PMD_SIZE;
+ contig_ptes = CONT_PMDS;
+ break;
+ case CONT_PTE_SIZE:
+ *pgsize = PAGE_SIZE;
+ contig_ptes = CONT_PTES;
+ break;
+ }
+
+ return contig_ptes;
+}
+
/*
* Changing some bits of contiguous entries requires us to follow a
* Break-Before-Make approach, breaking the whole contiguous set
@@ -245,6 +269,18 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
return entry;
}
+void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned long sz)
+{
+ int i, ncontig;
+ size_t pgsize;
+
+ ncontig = num_contig_ptes(sz, &pgsize);
+
+ for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
+ pte_clear(mm, addr, ptep);
+}
+
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3.1 8/11] arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages
2017-05-22 14:39 ` [PATCH v3 08/11] arm64: hugetlb: Override huge_pte_clear() to support " Punit Agrawal
@ 2017-05-22 16:45 ` Punit Agrawal
0 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 16:45 UTC (permalink / raw)
To: linux-arm-kernel
The default huge_pte_clear() implementation does not clear contiguous
page table entries when it encounters contiguous hugepages that are
supported on arm64.
Fix this by overriding the default implementation to clear all the
entries associated with contiguous hugepages.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: David Woods <dwoods@mellanox.com>
---
Changes since v3:
* Update patch to use #ifndef block to override huge_pte_clear()
arch/arm64/include/asm/hugetlb.h | 6 +++++-
arch/arm64/mm/hugetlbpage.c | 36 ++++++++++++++++++++++++++++++++++++
2 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index bbc1e35aa601..bb86f0741863 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -18,7 +18,6 @@
#ifndef __ASM_HUGETLB_H
#define __ASM_HUGETLB_H
-#include <asm-generic/hugetlb.h>
#include <asm/page.h>
static inline pte_t huge_ptep_get(pte_t *ptep)
@@ -82,5 +81,10 @@ extern void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep);
extern void huge_ptep_clear_flush(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep);
+extern void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned long sz);
+#define huge_pte_clear huge_pte_clear
+
+#include <asm-generic/hugetlb.h>
#endif /* __ASM_HUGETLB_H */
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index e9061704aec3..240b2fd53266 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -68,6 +68,30 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr,
return CONT_PTES;
}
+static inline int num_contig_ptes(unsigned long size, size_t *pgsize)
+{
+ int contig_ptes = 0;
+
+ *pgsize = size;
+
+ switch (size) {
+ case PUD_SIZE:
+ case PMD_SIZE:
+ contig_ptes = 1;
+ break;
+ case CONT_PMD_SIZE:
+ *pgsize = PMD_SIZE;
+ contig_ptes = CONT_PMDS;
+ break;
+ case CONT_PTE_SIZE:
+ *pgsize = PAGE_SIZE;
+ contig_ptes = CONT_PTES;
+ break;
+ }
+
+ return contig_ptes;
+}
+
/*
* Changing some bits of contiguous entries requires us to follow a
* Break-Before-Make approach, breaking the whole contiguous set
@@ -245,6 +269,18 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
return entry;
}
+void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned long sz)
+{
+ int i, ncontig;
+ size_t pgsize;
+
+ ncontig = num_contig_ptes(sz, &pgsize);
+
+ for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
+ pte_clear(mm, addr, ptep);
+}
+
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 09/11] arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous hugepages
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (8 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 08/11] arm64: hugetlb: Override huge_pte_clear() to support " Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 16:48 ` [PATCH v3.1 9/11] " Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 10/11] arm64: Re-enable support for " Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 11/11] arm64: hugetlb: Cleanup setup_hugepagesz Punit Agrawal
11 siblings, 1 reply; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
The default implementation of set_huge_swap_pte_at() does not support
hugepages consisting of contiguous ptes. Override it to add support for
contiguous hugepages.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: David Woods <dwoods@mellanox.com>
---
arch/arm64/mm/hugetlbpage.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 240b2fd53266..3e78673b1bcb 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -167,6 +167,18 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
}
}
+void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned long sz)
+{
+ int i, ncontig;
+ size_t pgsize;
+
+ ncontig = num_contig_ptes(sz, &pgsize);
+
+ for (i = 0; i < ncontig; i++, ptep++)
+ set_pte(ptep, pte);
+}
+
pte_t *huge_pte_alloc(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3.1 9/11] arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous hugepages
2017-05-22 14:39 ` [PATCH v3 09/11] arm64: hugetlb: Override set_huge_swap_pte_at() " Punit Agrawal
@ 2017-05-22 16:48 ` Punit Agrawal
0 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 16:48 UTC (permalink / raw)
To: linux-arm-kernel
The default implementation of set_huge_swap_pte_at() does not support
hugepages consisting of contiguous ptes. Override it to add support for
contiguous hugepages.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Cc: David Woods <dwoods@mellanox.com>
---
Changes since v3:
* Update patch based on core changes update to use #ifndef block
arch/arm64/include/asm/hugetlb.h | 3 +++
arch/arm64/mm/hugetlbpage.c | 12 ++++++++++++
2 files changed, 15 insertions(+)
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index bb86f0741863..e5f6210d1321 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -84,6 +84,9 @@ extern void huge_ptep_clear_flush(struct vm_area_struct *vma,
extern void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, unsigned long sz);
#define huge_pte_clear huge_pte_clear
+extern void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned long sz);
+#define set_huge_swap_pte_at set_huge_swap_pte_at
#include <asm-generic/hugetlb.h>
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 240b2fd53266..3e78673b1bcb 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -167,6 +167,18 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
}
}
+void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned long sz)
+{
+ int i, ncontig;
+ size_t pgsize;
+
+ ncontig = num_contig_ptes(sz, &pgsize);
+
+ for (i = 0; i < ncontig; i++, ptep++)
+ set_pte(ptep, pte);
+}
+
pte_t *huge_pte_alloc(struct mm_struct *mm,
unsigned long addr, unsigned long sz)
{
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread
* [PATCH v3 10/11] arm64: Re-enable support for contiguous hugepages
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (9 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 09/11] arm64: hugetlb: Override set_huge_swap_pte_at() " Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
2017-05-22 14:39 ` [PATCH v3 11/11] arm64: hugetlb: Cleanup setup_hugepagesz Punit Agrawal
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
also known as -
Revert "Revert "Revert "arm64: hugetlb: partial revert of 66b3923a1a0f"""
Now that our hugetlb implementation is compliant with the
break-before-make requirements of the architecture and we have addressed
some of the issues in core code required for properly dealing with
hardware poisoning of contiguous hugepages let's re-enable support for
contiguous hugepages.
This reverts commit 6ae979ab39a368c18ceb0424bf824d172d6ab56f.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 3e78673b1bcb..a10dfbd0ffd5 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -385,6 +385,10 @@ static __init int setup_hugepagesz(char *opt)
hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
} else if (ps == PUD_SIZE) {
hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
+ } else if (ps == (PAGE_SIZE * CONT_PTES)) {
+ hugetlb_add_hstate(CONT_PTE_SHIFT);
+ } else if (ps == (PMD_SIZE * CONT_PMDS)) {
+ hugetlb_add_hstate((PMD_SHIFT + CONT_PMD_SHIFT) - PAGE_SHIFT);
} else {
hugetlb_bad_size();
pr_err("hugepagesz: Unsupported page size %lu K\n", ps >> 10);
@@ -393,3 +397,13 @@ static __init int setup_hugepagesz(char *opt)
return 1;
}
__setup("hugepagesz=", setup_hugepagesz);
+
+#ifdef CONFIG_ARM64_64K_PAGES
+static __init int add_default_hugepagesz(void)
+{
+ if (size_to_hstate(CONT_PTES * PAGE_SIZE) == NULL)
+ hugetlb_add_hstate(CONT_PTE_SHIFT);
+ return 0;
+}
+arch_initcall(add_default_hugepagesz);
+#endif
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v3 11/11] arm64: hugetlb: Cleanup setup_hugepagesz
2017-05-22 14:39 [PATCH v3 00/11] arm64: Enable contiguous pte hugepage support Punit Agrawal
` (10 preceding siblings ...)
2017-05-22 14:39 ` [PATCH v3 10/11] arm64: Re-enable support for " Punit Agrawal
@ 2017-05-22 14:39 ` Punit Agrawal
11 siblings, 0 replies; 15+ messages in thread
From: Punit Agrawal @ 2017-05-22 14:39 UTC (permalink / raw)
To: linux-arm-kernel
From: Steve Capper <steve.capper@arm.com>
Replace a lot of if statements with switch and case labels to make it
much clearer which huge page sizes are supported.
Also, we prevent PUD_SIZE from being used on systems not running with
4KB PAGE_SIZE. Before if one supplied PUD_SIZE in these circumstances,
then unusuable huge page sizes would be in use.
Fixes: 084bd29810a5 ("ARM64: mm: HugeTLB support.")
Cc: David Woods <dwoods@mellanox.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
---
arch/arm64/mm/hugetlbpage.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index a10dfbd0ffd5..b5dc7cca3f45 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -381,20 +381,20 @@ static __init int setup_hugepagesz(char *opt)
{
unsigned long ps = memparse(opt, &opt);
- if (ps == PMD_SIZE) {
- hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
- } else if (ps == PUD_SIZE) {
- hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
- } else if (ps == (PAGE_SIZE * CONT_PTES)) {
- hugetlb_add_hstate(CONT_PTE_SHIFT);
- } else if (ps == (PMD_SIZE * CONT_PMDS)) {
- hugetlb_add_hstate((PMD_SHIFT + CONT_PMD_SHIFT) - PAGE_SHIFT);
- } else {
- hugetlb_bad_size();
- pr_err("hugepagesz: Unsupported page size %lu K\n", ps >> 10);
- return 0;
+ switch (ps) {
+#ifdef CONFIG_ARM64_4K_PAGES
+ case PUD_SIZE:
+#endif
+ case PMD_SIZE * CONT_PMDS:
+ case PMD_SIZE:
+ case PAGE_SIZE * CONT_PTES:
+ hugetlb_add_hstate(ilog2(ps) - PAGE_SHIFT);
+ return 1;
}
- return 1;
+
+ hugetlb_bad_size();
+ pr_err("hugepagesz: Unsupported page size %lu K\n", ps >> 10);
+ return 0;
}
__setup("hugepagesz=", setup_hugepagesz);
--
2.11.0
^ permalink raw reply related [flat|nested] 15+ messages in thread