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* [PATCH 0/3] mm/hugetlb: Add some new arch enabling macros
@ 2020-04-14 11:44 Anshuman Khandual
  2020-04-14 11:44 ` [PATCH 2/3] mm/hugetlb: Introduce HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE Anshuman Khandual
  2020-04-14 11:44 ` [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS Anshuman Khandual
  0 siblings, 2 replies; 8+ messages in thread
From: Anshuman Khandual @ 2020-04-14 11:44 UTC (permalink / raw)
  To: linux-mm
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Anshuman Khandual,
	Thomas Bogendoerfer, Borislav Petkov, Paul Walmsley,
	Thomas Gleixner, linux-arm-kernel, Tony Luck, linux-parisc,
	linux-mips, Palmer Dabbelt, linuxppc-dev, David S. Miller,
	Mike Kravetz

This series adds two macros which platforms can enable to override generic
fallback definitions. Before that it drops __HAVE_ARCH_HUGE_PTEP_GET from
arm64 platform.

1. HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE - is_hugepage_only_range()
2. HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS   - arch_clear_hugepage_flags()

This has been boot tested on arm64 and x86 platforms but built tested on
some more platforms including the changed ones here. This series applies
on v5.7-rc1. After this arm (32 bit) remains the sole platform defining
it's own huge_ptep_get() via __HAVE_ARCH_HUGE_PTEP_GET.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

Anshuman Khandual (3):
  arm64/mm: Drop __HAVE_ARCH_HUGE_PTEP_GET
  mm/hugetlb: Introduce HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE
  mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS

 arch/arm/include/asm/hugetlb.h     |  7 +------
 arch/arm64/include/asm/hugetlb.h   | 13 +------------
 arch/ia64/include/asm/hugetlb.h    |  5 +----
 arch/mips/include/asm/hugetlb.h    | 11 -----------
 arch/parisc/include/asm/hugetlb.h  | 10 ----------
 arch/powerpc/include/asm/hugetlb.h |  5 +----
 arch/riscv/include/asm/hugetlb.h   | 10 ----------
 arch/s390/include/asm/hugetlb.h    |  8 +-------
 arch/sh/include/asm/hugetlb.h      |  7 +------
 arch/sparc/include/asm/hugetlb.h   | 10 ----------
 arch/x86/include/asm/hugetlb.h     | 10 ----------
 include/linux/hugetlb.h            | 12 ++++++++++++
 12 files changed, 18 insertions(+), 90 deletions(-)

-- 
2.20.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 2/3] mm/hugetlb: Introduce HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE
  2020-04-14 11:44 [PATCH 0/3] mm/hugetlb: Add some new arch enabling macros Anshuman Khandual
@ 2020-04-14 11:44 ` Anshuman Khandual
  2020-04-14 11:44 ` [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS Anshuman Khandual
  1 sibling, 0 replies; 8+ messages in thread
From: Anshuman Khandual @ 2020-04-14 11:44 UTC (permalink / raw)
  To: linux-mm
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Anshuman Khandual,
	Thomas Bogendoerfer, Borislav Petkov, Paul Walmsley,
	Thomas Gleixner, linux-arm-kernel, Tony Luck, linux-parisc,
	linux-mips, Palmer Dabbelt, linuxppc-dev, David S. Miller,
	Mike Kravetz

There are multiple similar definitions for is_hugepage_only_range() across
platforms. This introduces HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE for platforms
that need to define their own is_hugepage_only_range() but otherwise there
is a generic fallback definition for others to use. This help reduce code
duplication.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 arch/arm/include/asm/hugetlb.h     | 6 ------
 arch/arm64/include/asm/hugetlb.h   | 6 ------
 arch/ia64/include/asm/hugetlb.h    | 1 +
 arch/mips/include/asm/hugetlb.h    | 7 -------
 arch/parisc/include/asm/hugetlb.h  | 6 ------
 arch/powerpc/include/asm/hugetlb.h | 1 +
 arch/riscv/include/asm/hugetlb.h   | 6 ------
 arch/s390/include/asm/hugetlb.h    | 7 -------
 arch/sh/include/asm/hugetlb.h      | 6 ------
 arch/sparc/include/asm/hugetlb.h   | 6 ------
 arch/x86/include/asm/hugetlb.h     | 6 ------
 include/linux/hugetlb.h            | 8 ++++++++
 12 files changed, 10 insertions(+), 56 deletions(-)

diff --git a/arch/arm/include/asm/hugetlb.h b/arch/arm/include/asm/hugetlb.h
index 318dcf5921ab..9ecd516d1ff7 100644
--- a/arch/arm/include/asm/hugetlb.h
+++ b/arch/arm/include/asm/hugetlb.h
@@ -14,12 +14,6 @@
 #include <asm/hugetlb-3level.h>
 #include <asm-generic/hugetlb.h>
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr, unsigned long len)
-{
-	return 0;
-}
-
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index b88878ddc88b..8f58e052697a 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -17,12 +17,6 @@
 extern bool arch_hugetlb_migration_supported(struct hstate *h);
 #endif
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr, unsigned long len)
-{
-	return 0;
-}
-
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/ia64/include/asm/hugetlb.h b/arch/ia64/include/asm/hugetlb.h
index 36cc0396b214..f17c1e228045 100644
--- a/arch/ia64/include/asm/hugetlb.h
+++ b/arch/ia64/include/asm/hugetlb.h
@@ -13,6 +13,7 @@ void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
 int prepare_hugepage_range(struct file *file,
 			unsigned long addr, unsigned long len);
 
+#define HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE
 static inline int is_hugepage_only_range(struct mm_struct *mm,
 					 unsigned long addr,
 					 unsigned long len)
diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index 425bb6fc3bda..8b201e281f67 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -11,13 +11,6 @@
 
 #include <asm/page.h>
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len)
-{
-	return 0;
-}
-
 #define __HAVE_ARCH_PREPARE_HUGEPAGE_RANGE
 static inline int prepare_hugepage_range(struct file *file,
 					 unsigned long addr,
diff --git a/arch/parisc/include/asm/hugetlb.h b/arch/parisc/include/asm/hugetlb.h
index 7cb595dcb7d7..411d9d867baa 100644
--- a/arch/parisc/include/asm/hugetlb.h
+++ b/arch/parisc/include/asm/hugetlb.h
@@ -12,12 +12,6 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep);
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len) {
-	return 0;
-}
-
 /*
  * If the arch doesn't supply something else, assume that hugepage
  * size aligned regions are ok without further preparation.
diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
index bd6504c28c2f..9dd50e1e4fe5 100644
--- a/arch/powerpc/include/asm/hugetlb.h
+++ b/arch/powerpc/include/asm/hugetlb.h
@@ -22,6 +22,7 @@ void flush_dcache_icache_hugepage(struct page *page);
 int slice_is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
 			   unsigned long len);
 
+#define HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE
 static inline int is_hugepage_only_range(struct mm_struct *mm,
 					 unsigned long addr,
 					 unsigned long len)
diff --git a/arch/riscv/include/asm/hugetlb.h b/arch/riscv/include/asm/hugetlb.h
index 728a5db66597..866f6ae6467c 100644
--- a/arch/riscv/include/asm/hugetlb.h
+++ b/arch/riscv/include/asm/hugetlb.h
@@ -5,12 +5,6 @@
 #include <asm-generic/hugetlb.h>
 #include <asm/page.h>
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len) {
-	return 0;
-}
-
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index de8f0bf5f238..7d27ea96ec2f 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -21,13 +21,6 @@ pte_t huge_ptep_get(pte_t *ptep);
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
 			      unsigned long addr, pte_t *ptep);
 
-static inline bool is_hugepage_only_range(struct mm_struct *mm,
-					  unsigned long addr,
-					  unsigned long len)
-{
-	return false;
-}
-
 /*
  * If the arch doesn't supply something else, assume that hugepage
  * size aligned regions are ok without further preparation.
diff --git a/arch/sh/include/asm/hugetlb.h b/arch/sh/include/asm/hugetlb.h
index 6f025fe18146..536ad2cb8aa4 100644
--- a/arch/sh/include/asm/hugetlb.h
+++ b/arch/sh/include/asm/hugetlb.h
@@ -5,12 +5,6 @@
 #include <asm/cacheflush.h>
 #include <asm/page.h>
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len) {
-	return 0;
-}
-
 /*
  * If the arch doesn't supply something else, assume that hugepage
  * size aligned regions are ok without further preparation.
diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
index 3963f80d1cb3..a056fe1119f5 100644
--- a/arch/sparc/include/asm/hugetlb.h
+++ b/arch/sparc/include/asm/hugetlb.h
@@ -20,12 +20,6 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep);
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len) {
-	return 0;
-}
-
 #define __HAVE_ARCH_HUGE_PTEP_CLEAR_FLUSH
 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 					 unsigned long addr, pte_t *ptep)
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index f65cfb48cfdd..cc98f79074d0 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -7,12 +7,6 @@
 
 #define hugepages_supported() boot_cpu_has(X86_FEATURE_PSE)
 
-static inline int is_hugepage_only_range(struct mm_struct *mm,
-					 unsigned long addr,
-					 unsigned long len) {
-	return 0;
-}
-
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 1e897e4168ac..2342e5a8d1dd 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -536,6 +536,14 @@ static inline unsigned int blocks_per_huge_page(struct hstate *h)
 
 #include <asm/hugetlb.h>
 
+#ifndef HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE
+static inline int is_hugepage_only_range(struct mm_struct *mm,
+					unsigned long addr, unsigned long len)
+{
+	return 0;
+}
+#endif
+
 #ifndef arch_make_huge_pte
 static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
 				       struct page *page, int writable)
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-04-14 11:44 [PATCH 0/3] mm/hugetlb: Add some new arch enabling macros Anshuman Khandual
  2020-04-14 11:44 ` [PATCH 2/3] mm/hugetlb: Introduce HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE Anshuman Khandual
@ 2020-04-14 11:44 ` Anshuman Khandual
  2020-04-26  0:55   ` Andrew Morton
  1 sibling, 1 reply; 8+ messages in thread
From: Anshuman Khandual @ 2020-04-14 11:44 UTC (permalink / raw)
  To: linux-mm
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Anshuman Khandual,
	Thomas Bogendoerfer, Borislav Petkov, Paul Walmsley,
	Thomas Gleixner, linux-arm-kernel, Tony Luck, linux-parisc,
	linux-mips, Palmer Dabbelt, linuxppc-dev, David S. Miller,
	Mike Kravetz

There are multiple similar definitions for arch_clear_hugepage_flags() on
various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
platforms that need to define their own arch_clear_hugepage_flags() while
also providing a generic fallback definition for others to use. This help
reduce code duplication.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: x86@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
 arch/arm/include/asm/hugetlb.h     | 1 +
 arch/arm64/include/asm/hugetlb.h   | 1 +
 arch/ia64/include/asm/hugetlb.h    | 4 ----
 arch/mips/include/asm/hugetlb.h    | 4 ----
 arch/parisc/include/asm/hugetlb.h  | 4 ----
 arch/powerpc/include/asm/hugetlb.h | 4 ----
 arch/riscv/include/asm/hugetlb.h   | 4 ----
 arch/s390/include/asm/hugetlb.h    | 1 +
 arch/sh/include/asm/hugetlb.h      | 1 +
 arch/sparc/include/asm/hugetlb.h   | 4 ----
 arch/x86/include/asm/hugetlb.h     | 4 ----
 include/linux/hugetlb.h            | 4 ++++
 12 files changed, 8 insertions(+), 28 deletions(-)

diff --git a/arch/arm/include/asm/hugetlb.h b/arch/arm/include/asm/hugetlb.h
index 9ecd516d1ff7..7107c1e6f020 100644
--- a/arch/arm/include/asm/hugetlb.h
+++ b/arch/arm/include/asm/hugetlb.h
@@ -14,6 +14,7 @@
 #include <asm/hugetlb-3level.h>
 #include <asm-generic/hugetlb.h>
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index 8f58e052697a..5369cf26a05d 100644
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -17,6 +17,7 @@
 extern bool arch_hugetlb_migration_supported(struct hstate *h);
 #endif
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/ia64/include/asm/hugetlb.h b/arch/ia64/include/asm/hugetlb.h
index f17c1e228045..2ecff18a32e5 100644
--- a/arch/ia64/include/asm/hugetlb.h
+++ b/arch/ia64/include/asm/hugetlb.h
@@ -28,10 +28,6 @@ static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 {
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* _ASM_IA64_HUGETLB_H */
diff --git a/arch/mips/include/asm/hugetlb.h b/arch/mips/include/asm/hugetlb.h
index 8b201e281f67..10e3be870df7 100644
--- a/arch/mips/include/asm/hugetlb.h
+++ b/arch/mips/include/asm/hugetlb.h
@@ -75,10 +75,6 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 	return changed;
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* __ASM_HUGETLB_H */
diff --git a/arch/parisc/include/asm/hugetlb.h b/arch/parisc/include/asm/hugetlb.h
index 411d9d867baa..a69cf9efb0c1 100644
--- a/arch/parisc/include/asm/hugetlb.h
+++ b/arch/parisc/include/asm/hugetlb.h
@@ -42,10 +42,6 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 					     unsigned long addr, pte_t *ptep,
 					     pte_t pte, int dirty);
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #endif /* _ASM_PARISC64_HUGETLB_H */
diff --git a/arch/powerpc/include/asm/hugetlb.h b/arch/powerpc/include/asm/hugetlb.h
index 9dd50e1e4fe5..d259e056e6cf 100644
--- a/arch/powerpc/include/asm/hugetlb.h
+++ b/arch/powerpc/include/asm/hugetlb.h
@@ -61,10 +61,6 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 			       unsigned long addr, pte_t *ptep,
 			       pte_t pte, int dirty);
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #include <asm-generic/hugetlb.h>
 
 #else /* ! CONFIG_HUGETLB_PAGE */
diff --git a/arch/riscv/include/asm/hugetlb.h b/arch/riscv/include/asm/hugetlb.h
index 866f6ae6467c..a5c2ca1d1cd8 100644
--- a/arch/riscv/include/asm/hugetlb.h
+++ b/arch/riscv/include/asm/hugetlb.h
@@ -5,8 +5,4 @@
 #include <asm-generic/hugetlb.h>
 #include <asm/page.h>
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #endif /* _ASM_RISCV_HUGETLB_H */
diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index 7d27ea96ec2f..9f067a66609b 100644
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -35,6 +35,7 @@ static inline int prepare_hugepage_range(struct file *file,
 	return 0;
 }
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_arch_1, &page->flags);
diff --git a/arch/sh/include/asm/hugetlb.h b/arch/sh/include/asm/hugetlb.h
index 536ad2cb8aa4..869b5a947f07 100644
--- a/arch/sh/include/asm/hugetlb.h
+++ b/arch/sh/include/asm/hugetlb.h
@@ -26,6 +26,7 @@ static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
 {
 }
 
+#define HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
 static inline void arch_clear_hugepage_flags(struct page *page)
 {
 	clear_bit(PG_dcache_clean, &page->flags);
diff --git a/arch/sparc/include/asm/hugetlb.h b/arch/sparc/include/asm/hugetlb.h
index a056fe1119f5..53838a173f62 100644
--- a/arch/sparc/include/asm/hugetlb.h
+++ b/arch/sparc/include/asm/hugetlb.h
@@ -47,10 +47,6 @@ static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
 	return changed;
 }
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #define __HAVE_ARCH_HUGETLB_FREE_PGD_RANGE
 void hugetlb_free_pgd_range(struct mmu_gather *tlb, unsigned long addr,
 			    unsigned long end, unsigned long floor,
diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index cc98f79074d0..1721b1aadeb1 100644
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -7,8 +7,4 @@
 
 #define hugepages_supported() boot_cpu_has(X86_FEATURE_PSE)
 
-static inline void arch_clear_hugepage_flags(struct page *page)
-{
-}
-
 #endif /* _ASM_X86_HUGETLB_H */
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 2342e5a8d1dd..359cfa1b6f54 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
 }
 #endif
 
+#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
+static inline void arch_clear_hugepage_flags(struct page *page) { }
+#endif
+
 #ifndef arch_make_huge_pte
 static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
 				       struct page *page, int writable)
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* Re: [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-04-14 11:44 ` [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS Anshuman Khandual
@ 2020-04-26  0:55   ` Andrew Morton
  2020-04-26  2:43     ` Anshuman Khandual
  0 siblings, 1 reply; 8+ messages in thread
From: Andrew Morton @ 2020-04-26  0:55 UTC (permalink / raw)
  To: Anshuman Khandual
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley, linux-mm,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Thomas Bogendoerfer,
	Borislav Petkov, Paul Walmsley, Thomas Gleixner,
	linux-arm-kernel, Tony Luck, linux-parisc, linux-mips,
	Palmer Dabbelt, linuxppc-dev, David S. Miller, Mike Kravetz

On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> There are multiple similar definitions for arch_clear_hugepage_flags() on
> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
> platforms that need to define their own arch_clear_hugepage_flags() while
> also providing a generic fallback definition for others to use. This help
> reduce code duplication.
> 
> ...
>
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>  }
>  #endif
>  
> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
> +static inline void arch_clear_hugepage_flags(struct page *page) { }
> +#endif
> +
>  #ifndef arch_make_huge_pte
>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>  				       struct page *page, int writable)

This is the rather old-school way of doing it.  The Linus-suggested way is

#ifndef arch_clear_hugepage_flags
static inline void arch_clear_hugepage_flags(struct page *page)
{
}
#define arch_clear_hugepage_flags arch_clear_hugepage_flags
#endif

And the various arch headers do

static inline void arch_clear_hugepage_flags(struct page *page)
{
	<some implementation>
}
#define arch_clear_hugepage_flags arch_clear_hugepage_flags

It's a small difference - mainly to avoid adding two variables to the
overall namespace where one would do.


^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-04-26  0:55   ` Andrew Morton
@ 2020-04-26  2:43     ` Anshuman Khandual
  2020-04-26  3:01       ` Andrew Morton
  0 siblings, 1 reply; 8+ messages in thread
From: Anshuman Khandual @ 2020-04-26  2:43 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley, linux-mm,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Thomas Bogendoerfer,
	Borislav Petkov, Paul Walmsley, Thomas Gleixner,
	linux-arm-kernel, Tony Luck, linux-parisc, linux-mips,
	Palmer Dabbelt, linuxppc-dev, David S. Miller, Mike Kravetz



On 04/26/2020 06:25 AM, Andrew Morton wrote:
> On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> 
>> There are multiple similar definitions for arch_clear_hugepage_flags() on
>> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
>> platforms that need to define their own arch_clear_hugepage_flags() while
>> also providing a generic fallback definition for others to use. This help
>> reduce code duplication.
>>
>> ...
>>
>> --- a/include/linux/hugetlb.h
>> +++ b/include/linux/hugetlb.h
>> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>>  }
>>  #endif
>>  
>> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
>> +static inline void arch_clear_hugepage_flags(struct page *page) { }
>> +#endif
>> +
>>  #ifndef arch_make_huge_pte
>>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>>  				       struct page *page, int writable)
> 
> This is the rather old-school way of doing it.  The Linus-suggested way is
> 
> #ifndef arch_clear_hugepage_flags
> static inline void arch_clear_hugepage_flags(struct page *page)
> {
> }
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags

Do we need that above line here ? Is not that implicit.

> #endif
> 
> And the various arch headers do
> 
> static inline void arch_clear_hugepage_flags(struct page *page)
> {
> 	<some implementation>
> }
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> It's a small difference - mainly to avoid adding two variables to the
> overall namespace where one would do.

Understood, will change and resend.

> 
> 

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-04-26  2:43     ` Anshuman Khandual
@ 2020-04-26  3:01       ` Andrew Morton
  2020-05-05  2:51         ` Anshuman Khandual
  0 siblings, 1 reply; 8+ messages in thread
From: Andrew Morton @ 2020-04-26  3:01 UTC (permalink / raw)
  To: Anshuman Khandual
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley, linux-mm,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Thomas Bogendoerfer,
	Borislav Petkov, Paul Walmsley, Thomas Gleixner,
	linux-arm-kernel, Tony Luck, linux-parisc, linux-mips,
	Palmer Dabbelt, linuxppc-dev, David S. Miller, Mike Kravetz

On Sun, 26 Apr 2020 08:13:17 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> 
> 
> On 04/26/2020 06:25 AM, Andrew Morton wrote:
> > On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> > 
> >> There are multiple similar definitions for arch_clear_hugepage_flags() on
> >> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
> >> platforms that need to define their own arch_clear_hugepage_flags() while
> >> also providing a generic fallback definition for others to use. This help
> >> reduce code duplication.
> >>
> >> ...
> >>
> >> --- a/include/linux/hugetlb.h
> >> +++ b/include/linux/hugetlb.h
> >> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
> >>  }
> >>  #endif
> >>  
> >> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
> >> +static inline void arch_clear_hugepage_flags(struct page *page) { }
> >> +#endif
> >> +
> >>  #ifndef arch_make_huge_pte
> >>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
> >>  				       struct page *page, int writable)
> > 
> > This is the rather old-school way of doing it.  The Linus-suggested way is
> > 
> > #ifndef arch_clear_hugepage_flags
> > static inline void arch_clear_hugepage_flags(struct page *page)
> > {
> > }
> > #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> Do we need that above line here ? Is not that implicit.

It depends if other header files want to test whether
arch_clear_hugepage_flags is already defined.  If the header heorarchy
is well-defined and working properly, they shouldn't need to, because
we're reliably indluding the relevant arch header before (or early
within) include/linux/hugetlb.h.

It would be nice if

#define arch_clear_hugepage_flags arch_clear_hugepage_flags
#define arch_clear_hugepage_flags arch_clear_hugepage_flags

were to generate an compiler error but it doesn't.  If it did we could
detect these incorrect inclusion orders.

> > #endif
> > 
> > And the various arch headers do
> > 
> > static inline void arch_clear_hugepage_flags(struct page *page)
> > {
> > 	<some implementation>
> > }
> > #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> > 
> > It's a small difference - mainly to avoid adding two variables to the
> > overall namespace where one would do.
> 
> Understood, will change and resend.

That's OK - I've queued up that fix.

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-04-26  3:01       ` Andrew Morton
@ 2020-05-05  2:51         ` Anshuman Khandual
  2020-05-05 20:12           ` Andrew Morton
  0 siblings, 1 reply; 8+ messages in thread
From: Anshuman Khandual @ 2020-05-05  2:51 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley, linux-mm,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Thomas Bogendoerfer,
	Borislav Petkov, Paul Walmsley, Thomas Gleixner,
	linux-arm-kernel, Tony Luck, linux-parisc, linux-mips,
	Palmer Dabbelt, linuxppc-dev, David S. Miller, Mike Kravetz



On 04/26/2020 08:31 AM, Andrew Morton wrote:
> On Sun, 26 Apr 2020 08:13:17 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
> 
>>
>>
>> On 04/26/2020 06:25 AM, Andrew Morton wrote:
>>> On Tue, 14 Apr 2020 17:14:30 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:
>>>
>>>> There are multiple similar definitions for arch_clear_hugepage_flags() on
>>>> various platforms. This introduces HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS for those
>>>> platforms that need to define their own arch_clear_hugepage_flags() while
>>>> also providing a generic fallback definition for others to use. This help
>>>> reduce code duplication.
>>>>
>>>> ...
>>>>
>>>> --- a/include/linux/hugetlb.h
>>>> +++ b/include/linux/hugetlb.h
>>>> @@ -544,6 +544,10 @@ static inline int is_hugepage_only_range(struct mm_struct *mm,
>>>>  }
>>>>  #endif
>>>>  
>>>> +#ifndef HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
>>>> +static inline void arch_clear_hugepage_flags(struct page *page) { }
>>>> +#endif
>>>> +
>>>>  #ifndef arch_make_huge_pte
>>>>  static inline pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
>>>>  				       struct page *page, int writable)
>>>
>>> This is the rather old-school way of doing it.  The Linus-suggested way is
>>>
>>> #ifndef arch_clear_hugepage_flags
>>> static inline void arch_clear_hugepage_flags(struct page *page)
>>> {
>>> }
>>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
>>
>> Do we need that above line here ? Is not that implicit.
> 
> It depends if other header files want to test whether
> arch_clear_hugepage_flags is already defined.  If the header heorarchy
> is well-defined and working properly, they shouldn't need to, because
> we're reliably indluding the relevant arch header before (or early
> within) include/linux/hugetlb.h.
> 
> It would be nice if
> 
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> 
> were to generate an compiler error but it doesn't.  If it did we could
> detect these incorrect inclusion orders.
> 
>>> #endif
>>>
>>> And the various arch headers do
>>>
>>> static inline void arch_clear_hugepage_flags(struct page *page)
>>> {
>>> 	<some implementation>
>>> }
>>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
>>>
>>> It's a small difference - mainly to avoid adding two variables to the
>>> overall namespace where one would do.
>>
>> Understood, will change and resend.
> 
> That's OK - I've queued up that fix.
>

Hello Andrew,

I might not have searched all the relevant trees or might have just searched
earlier than required. But I dont see these patches (or your proposed fixes)
either in mmotm (2020-04-29-23-04) or in next-20200504. Wondering if you are
waiting on a V2 for this series accommodating the changes you had proposed.

- Anshuman

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS
  2020-05-05  2:51         ` Anshuman Khandual
@ 2020-05-05 20:12           ` Andrew Morton
  0 siblings, 0 replies; 8+ messages in thread
From: Andrew Morton @ 2020-05-05 20:12 UTC (permalink / raw)
  To: Anshuman Khandual
  Cc: Rich Felker, linux-ia64, linux-sh, Catalin Marinas,
	Heiko Carstens, linux-kernel, James E.J. Bottomley, linux-mm,
	Paul Mackerras, H. Peter Anvin, sparclinux, linux-riscv,
	Will Deacon, linux-arch, linux-s390, Yoshinori Sato,
	Helge Deller, x86, Russell King, Christian Borntraeger,
	Ingo Molnar, Fenghua Yu, Vasily Gorbik, Thomas Bogendoerfer,
	Borislav Petkov, Paul Walmsley, Thomas Gleixner,
	linux-arm-kernel, Tony Luck, linux-parisc, linux-mips,
	Palmer Dabbelt, linuxppc-dev, David S. Miller, Mike Kravetz

On Tue, 5 May 2020 08:21:34 +0530 Anshuman Khandual <anshuman.khandual@arm.com> wrote:

> >>> static inline void arch_clear_hugepage_flags(struct page *page)
> >>> {
> >>> 	<some implementation>
> >>> }
> >>> #define arch_clear_hugepage_flags arch_clear_hugepage_flags
> >>>
> >>> It's a small difference - mainly to avoid adding two variables to the
> >>> overall namespace where one would do.
> >>
> >> Understood, will change and resend.
> > 
> > That's OK - I've queued up that fix.
> >
> 
> Hello Andrew,
> 
> I might not have searched all the relevant trees or might have just searched
> earlier than required. But I dont see these patches (or your proposed fixes)
> either in mmotm (2020-04-29-23-04) or in next-20200504. Wondering if you are
> waiting on a V2 for this series accommodating the changes you had proposed.

hm.  I think I must have got confused and thought you were referring to
a different patch.  Yes please, let's have v2.

^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2020-05-05 20:14 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-04-14 11:44 [PATCH 0/3] mm/hugetlb: Add some new arch enabling macros Anshuman Khandual
2020-04-14 11:44 ` [PATCH 2/3] mm/hugetlb: Introduce HAVE_ARCH_IS_HUGEPAGE_ONLY_RANGE Anshuman Khandual
2020-04-14 11:44 ` [PATCH 3/3] mm/hugetlb: Introduce HAVE_ARCH_CLEAR_HUGEPAGE_FLAGS Anshuman Khandual
2020-04-26  0:55   ` Andrew Morton
2020-04-26  2:43     ` Anshuman Khandual
2020-04-26  3:01       ` Andrew Morton
2020-05-05  2:51         ` Anshuman Khandual
2020-05-05 20:12           ` Andrew Morton

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