date:20191006

[PATCH V4 2/2] mm/pgtable/debug: Add test validating architecture page table helpers

2019-10-06 Thread Anshuman Khandual

This adds a test module which will validate architecture page table helpers
and accessors regarding compliance with generic MM semantics expectations.
This will help various architectures in validating changes to the existing
page table helpers or addition of new ones.

Test page table and memory pages creating it's entries at various level are
all allocated from system memory with required alignments. If memory pages
with required size and alignment could not be allocated, then all depending
individual tests are skipped.

Cc: Andrew Morton 
Cc: Vlastimil Babka 
Cc: Greg Kroah-Hartman 
Cc: Thomas Gleixner 
Cc: Mike Rapoport 
Cc: Jason Gunthorpe 
Cc: Dan Williams 
Cc: Peter Zijlstra 
Cc: Michal Hocko 
Cc: Mark Rutland 
Cc: Mark Brown 
Cc: Steven Price 
Cc: Ard Biesheuvel 
Cc: Masahiro Yamada 
Cc: Kees Cook 
Cc: Tetsuo Handa 
Cc: Matthew Wilcox 
Cc: Sri Krishna chowdary 
Cc: Dave Hansen 
Cc: Russell King - ARM Linux 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: "David S. Miller" 
Cc: Vineet Gupta 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Ralf Baechle 
Cc: Kirill A. Shutemov 
Cc: Gerald Schaefer 
Cc: Christophe Leroy 
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-m...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-i...@vger.kernel.org
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux-s...@vger.kernel.org
Cc: linux...@vger.kernel.org
Cc: sparcli...@vger.kernel.org
Cc: x...@kernel.org
Cc: linux-ker...@vger.kernel.org

Suggested-by: Catalin Marinas 
Signed-off-by: Christophe Leroy 
Tested-by: Christophe Leroy#PPC32
Signed-off-by: Anshuman Khandual 
---
 arch/x86/include/asm/pgtable_64_types.h |   2 +
 mm/Kconfig.debug|  15 +
 mm/Makefile |   1 +
 mm/arch_pgtable_test.c  | 440 
 4 files changed, 458 insertions(+)
 create mode 100644 mm/arch_pgtable_test.c

diff --git a/arch/x86/include/asm/pgtable_64_types.h 
b/arch/x86/include/asm/pgtable_64_types.h
index 52e5f5f2240d..b882792a3999 100644
--- a/arch/x86/include/asm/pgtable_64_types.h
+++ b/arch/x86/include/asm/pgtable_64_types.h
@@ -40,6 +40,8 @@ static inline bool pgtable_l5_enabled(void)
 #define pgtable_l5_enabled() 0
 #endif /* CONFIG_X86_5LEVEL */
 
+#define mm_p4d_folded(mm) (!pgtable_l5_enabled())
+
 extern unsigned int pgdir_shift;
 extern unsigned int ptrs_per_p4d;
 
diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index 327b3ebf23bf..683131b1ee7d 100644
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -117,3 +117,18 @@ config DEBUG_RODATA_TEST
 depends on STRICT_KERNEL_RWX
 ---help---
   This option enables a testcase for the setting rodata read-only.
+
+config DEBUG_ARCH_PGTABLE_TEST
+   bool "Test arch page table helpers for semantics compliance"
+   depends on MMU
+   depends on DEBUG_KERNEL
+   depends on !(ARM || IA64)
+   help
+ This options provides a kernel module which can be used to test
+ architecture page table helper functions on various platform in
+ verifying if they comply with expected generic MM semantics. This
+ will help architectures code in making sure that any changes or
+ new additions of these helpers will still conform to generic MM
+ expected semantics.
+
+ If unsure, say N.
diff --git a/mm/Makefile b/mm/Makefile
index d996846697ef..bb572c5aa8c5 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -86,6 +86,7 @@ obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o
 obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
 obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
 obj-$(CONFIG_DEBUG_RODATA_TEST) += rodata_test.o
+obj-$(CONFIG_DEBUG_ARCH_PGTABLE_TEST) += arch_pgtable_test.o
 obj-$(CONFIG_PAGE_OWNER) += page_owner.o
 obj-$(CONFIG_CLEANCACHE) += cleancache.o
 obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o
diff --git a/mm/arch_pgtable_test.c b/mm/arch_pgtable_test.c
new file mode 100644
index ..2942a0484d63
--- /dev/null
+++ b/mm/arch_pgtable_test.c
@@ -0,0 +1,440 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This kernel module validates architecture page table helpers &
+ * accessors and helps in verifying their continued compliance with
+ * generic MM semantics.
+ *
+ * Copyright (C) 2019 ARM Ltd.
+ *
+ * Author: Anshuman Khandual 
+ */
+#define pr_fmt(fmt) "arch_pgtable_test: %s " fmt, __func__
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/*
+ * Basic operations
+ *
+ * mkold(entry)= An old and not a young entry
+ * mkyoung(entry)  = A young and not an old entry
+ * mkdirty(entry)  = A dirty and not a clean entry
+ * mkclean(entry)  = A clean and not a dirty entry
+ * mkwrite(entry)  = A write and not a write protected entry
+ * wrprotect(entry

[PATCH V4 0/2] mm/debug: Add tests for architecture exported page table helpers

2019-10-06 Thread Anshuman Khandual

This series adds a test validation for architecture exported page table
helpers. Patch in the series adds basic transformation tests at various
levels of the page table. Before that it exports gigantic page allocation
function from HugeTLB.

This test was originally suggested by Catalin during arm64 THP migration
RFC discussion earlier. Going forward it can include more specific tests
with respect to various generic MM functions like THP, HugeTLB etc and
platform specific tests.

https://lore.kernel.org/linux-mm/20190628102003.ga56...@arrakis.emea.arm.com/

Changes in V4:

- Disable DEBUG_ARCH_PGTABLE_TEST for ARM and IA64 platforms

Changes in V3: 
(https://lore.kernel.org/patchwork/project/lkml/list/?series=411216)

- Changed test trigger from module format into late_initcall()
- Marked all functions with __init to be freed after completion
- Changed all __PGTABLE_PXX_FOLDED checks as mm_pxx_folded()
- Folded in PPC32 fixes from Christophe

Changes in V2:

https://lore.kernel.org/linux-mm/1568268173-31302-1-git-send-email-anshuman.khand...@arm.com/T/#t

- Fixed small typo error in MODULE_DESCRIPTION()
- Fixed m64k build problems for lvalue concerns in pmd_xxx_tests()
- Fixed dynamic page table level folding problems on x86 as per Kirril
- Fixed second pointers during pxx_populate_tests() per Kirill and Gerald
- Allocate and free pte table with pte_alloc_one/pte_free per Kirill
- Modified pxx_clear_tests() to accommodate s390 lower 12 bits situation
- Changed RANDOM_NZVALUE value from 0xbe to 0xff
- Changed allocation, usage, free sequence for saved_ptep
- Renamed VMA_FLAGS as VMFLAGS
- Implemented a new method for random vaddr generation
- Implemented some other cleanups
- Dropped extern reference to mm_alloc()
- Created and exported new alloc_gigantic_page_order()
- Dropped the custom allocator and used new alloc_gigantic_page_order()

Changes in V1:

https://lore.kernel.org/linux-mm/1567497706-8649-1-git-send-email-anshuman.khand...@arm.com/

- Added fallback mechanism for PMD aligned memory allocation failure

Changes in RFC V2:

https://lore.kernel.org/linux-mm/1565335998-22553-1-git-send-email-anshuman.khand...@arm.com/T/#u

- Moved test module and it's config from lib/ to mm/
- Renamed config TEST_ARCH_PGTABLE as DEBUG_ARCH_PGTABLE_TEST
- Renamed file from test_arch_pgtable.c to arch_pgtable_test.c
- Added relevant MODULE_DESCRIPTION() and MODULE_AUTHOR() details
- Dropped loadable module config option
- Basic tests now use memory blocks with required size and alignment
- PUD aligned memory block gets allocated with alloc_contig_range()
- If PUD aligned memory could not be allocated it falls back on PMD aligned
  memory block from page allocator and pud_* tests are skipped
- Clear and populate tests now operate on real in memory page table entries
- Dummy mm_struct gets allocated with mm_alloc()
- Dummy page table entries get allocated with [pud|pmd|pte]_alloc_[map]()
- Simplified [p4d|pgd]_basic_tests(), now has random values in the entries

Original RFC V1:

https://lore.kernel.org/linux-mm/1564037723-26676-1-git-send-email-anshuman.khand...@arm.com/

Cc: Andrew Morton 
Cc: Vlastimil Babka 
Cc: Greg Kroah-Hartman 
Cc: Thomas Gleixner 
Cc: Mike Rapoport 
Cc: Jason Gunthorpe 
Cc: Dan Williams 
Cc: Peter Zijlstra 
Cc: Michal Hocko 
Cc: Mark Rutland 
Cc: Mark Brown 
Cc: Steven Price 
Cc: Ard Biesheuvel 
Cc: Masahiro Yamada 
Cc: Kees Cook 
Cc: Tetsuo Handa 
Cc: Matthew Wilcox 
Cc: Sri Krishna chowdary 
Cc: Dave Hansen 
Cc: Russell King - ARM Linux 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: "David S. Miller" 
Cc: Vineet Gupta 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Ralf Baechle 
Cc: Kirill A. Shutemov 
Cc: Gerald Schaefer 
Cc: Christophe Leroy 
Cc: Mike Kravetz 
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-m...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-i...@vger.kernel.org
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux-s...@vger.kernel.org
Cc: linux...@vger.kernel.org
Cc: sparcli...@vger.kernel.org
Cc: x...@kernel.org
Cc: linux-ker...@vger.kernel.org

Anshuman Khandual (2):
  mm/hugetlb: Make alloc_gigantic_page() available for general use
  mm/pgtable/debug: Add test validating architecture page table helpers

 arch/x86/include/asm/pgtable_64_types.h |   2 +
 include/linux/hugetlb.h |   9 +
 mm/Kconfig.debug|  15 +
 mm/Makefile |   1 +
 mm/arch_pgtable_test.c  | 440 
 mm/hugetlb.c|  24 +-
 6 files changed, 489 insertions(+), 2 deletions(-)
 create mode 100644 mm/arch_pgtable_test.c

-- 
2.20.1


___
linux-snps-arc mailing list
linux-snps-arc@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-snps-arc

[PATCH V4 1/2] mm/hugetlb: Make alloc_gigantic_page() available for general use

2019-10-06 Thread Anshuman Khandual

alloc_gigantic_page() implements an allocation method where it scans over
various zones looking for a large contiguous memory block which could not
have been allocated through the buddy allocator. A subsequent patch which
tests arch page table helpers needs such a method to allocate PUD_SIZE
sized memory block. In the future such methods might have other use cases
as well. So alloc_gigantic_page() has been split carving out actual memory
allocation method and made available via new alloc_gigantic_page_order().

Cc: Andrew Morton 
Cc: Vlastimil Babka 
Cc: Greg Kroah-Hartman 
Cc: Thomas Gleixner 
Cc: Mike Rapoport 
Cc: Mike Kravetz 
Cc: Jason Gunthorpe 
Cc: Dan Williams 
Cc: Peter Zijlstra 
Cc: Michal Hocko 
Cc: Mark Rutland 
Cc: Mark Brown 
Cc: Steven Price 
Cc: Ard Biesheuvel 
Cc: Masahiro Yamada 
Cc: Kees Cook 
Cc: Tetsuo Handa 
Cc: Matthew Wilcox 
Cc: Sri Krishna chowdary 
Cc: Dave Hansen 
Cc: Russell King - ARM Linux 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: "David S. Miller" 
Cc: Vineet Gupta 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Ralf Baechle 
Cc: Kirill A. Shutemov 
Cc: Gerald Schaefer 
Cc: Christophe Leroy 
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-m...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-i...@vger.kernel.org
Cc: linuxppc-...@lists.ozlabs.org
Cc: linux-s...@vger.kernel.org
Cc: linux...@vger.kernel.org
Cc: sparcli...@vger.kernel.org
Cc: x...@kernel.org
Cc: linux-ker...@vger.kernel.org
Signed-off-by: Anshuman Khandual 
---
 include/linux/hugetlb.h |  9 +
 mm/hugetlb.c| 24 ++--
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 53fc34f930d0..cc50d5ad4885 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -299,6 +299,9 @@ static inline bool is_file_hugepages(struct file *file)
 }
 
 
+struct page *
+alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
+ int nid, nodemask_t *nodemask);
 #else /* !CONFIG_HUGETLBFS */
 
 #define is_file_hugepages(file)false
@@ -310,6 +313,12 @@ hugetlb_file_setup(const char *name, size_t size, 
vm_flags_t acctflag,
return ERR_PTR(-ENOSYS);
 }
 
+static inline struct page *
+alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
+ int nid, nodemask_t *nodemask)
+{
+   return NULL;
+}
 #endif /* !CONFIG_HUGETLBFS */
 
 #ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ef37c85423a5..3fb81252f52b 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1112,10 +1112,9 @@ static bool zone_spans_last_pfn(const struct zone *zone,
return zone_spans_pfn(zone, last_pfn);
 }
 
-static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
+struct page *alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
int nid, nodemask_t *nodemask)
 {
-   unsigned int order = huge_page_order(h);
unsigned long nr_pages = 1 << order;
unsigned long ret, pfn, flags;
struct zonelist *zonelist;
@@ -1151,6 +1150,14 @@ static struct page *alloc_gigantic_page(struct hstate 
*h, gfp_t gfp_mask,
return NULL;
 }
 
+static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
+   int nid, nodemask_t *nodemask)
+{
+   unsigned int order = huge_page_order(h);
+
+   return alloc_gigantic_page_order(order, gfp_mask, nid, nodemask);
+}
+
 static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
 static void prep_compound_gigantic_page(struct page *page, unsigned int order);
 #else /* !CONFIG_CONTIG_ALLOC */
@@ -1159,6 +1166,12 @@ static struct page *alloc_gigantic_page(struct hstate 
*h, gfp_t gfp_mask,
 {
return NULL;
 }
+
+struct page *alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
+  int nid, nodemask_t *nodemask)
+{
+   return NULL;
+}
 #endif /* CONFIG_CONTIG_ALLOC */
 
 #else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
@@ -1167,6 +1180,13 @@ static struct page *alloc_gigantic_page(struct hstate 
*h, gfp_t gfp_mask,
 {
return NULL;
 }
+
+struct page *alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
+  int nid, nodemask_t *nodemask)
+{
+   return NULL;
+}
+
 static inline void free_gigantic_page(struct page *page, unsigned int order) { 
}
 static inline void destroy_compound_gigantic_page(struct page *page,
unsigned int order) { }
-- 
2.20.1


___
linux-snps-arc mailing list
linux-snps-arc@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-snps-arc

[PATCH V4 2/2] mm/pgtable/debug: Add test validating architecture page table helpers

[PATCH V4 0/2] mm/debug: Add tests for architecture exported page table helpers

[PATCH V4 1/2] mm/hugetlb: Make alloc_gigantic_page() available for general use

3 matches

Site Navigation

Mail list logo

Footer information