mm/hugetlb: clean up ARCH_HAS_GIGANTIC_PAGE

This moves the #ifdef in C code to a Kconfig dependency.  Also we move
the gigantic_page_supported() function to be arch specific.

This allows architectures to conditionally enable runtime allocation of
gigantic huge page.  Architectures like ppc64 supports different
gigantic huge page size (16G and 1G) based on the translation mode
selected.  This provides an opportunity for ppc64 to enable runtime
allocation only w.r.t 1G hugepage.

No functional change in this patch.

Link: http://lkml.kernel.org/r/1494995292-4443-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9f7a934ff707a00b8495ab0ca533fb86468d3aba..ff925ece82d66080b775b83be7fa7190df0f4ac5 100644 (file)
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -13,7 +13,7 @@ config ARM64
        select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
        select ARCH_HAS_ELF_RANDOMIZE
        select ARCH_HAS_GCOV_PROFILE_ALL
-       select ARCH_HAS_GIGANTIC_PAGE
+       select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
        select ARCH_HAS_KCOV
        select ARCH_HAS_SET_MEMORY
        select ARCH_HAS_SG_CHAIN

diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h
index bbc1e35aa6014c8ea83a1c06acbea83da250121d..793bd73b0d0788903820cd60fe8affedb97ae126 100644 (file)
--- a/arch/arm64/include/asm/hugetlb.h
+++ b/arch/arm64/include/asm/hugetlb.h
@@ -83,4 +83,8 @@ extern void huge_ptep_set_wrprotect(struct mm_struct *mm,
 extern void huge_ptep_clear_flush(struct vm_area_struct *vma,
                                  unsigned long addr, pte_t *ptep);
 
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void) { return true; }
+#endif
+
 #endif /* __ASM_HUGETLB_H */

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 37abe86e5bc922743667f389af4c745009f5db14..7eeb75d758c196449e6ed90527c731b945e97e49 100644 (file)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -68,7 +68,7 @@ config S390
        select ARCH_HAS_DEVMEM_IS_ALLOWED
        select ARCH_HAS_ELF_RANDOMIZE
        select ARCH_HAS_GCOV_PROFILE_ALL
-       select ARCH_HAS_GIGANTIC_PAGE
+       select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
        select ARCH_HAS_KCOV
        select ARCH_HAS_SET_MEMORY
        select ARCH_HAS_SG_CHAIN

diff --git a/arch/s390/include/asm/hugetlb.h b/arch/s390/include/asm/hugetlb.h
index cd546a245c68bf08d40d17bfc0bf7b3f647c3a22..89057b2cc8fe07da43a4f5059f64a9f7e7c31263 100644 (file)
--- a/arch/s390/include/asm/hugetlb.h
+++ b/arch/s390/include/asm/hugetlb.h
@@ -112,4 +112,7 @@ static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
        return pte_modify(pte, newprot);
 }
 
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void) { return true; }
+#endif
 #endif /* _ASM_S390_HUGETLB_H */

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1dbbe38f6ec0f63b1e3bedf5232673e4c8a498c9..fe53a3aa805a93612ca3d35434b786c4054b0bc7 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -22,7 +22,7 @@ config X86_64
        def_bool y
        depends on 64BIT
        # Options that are inherently 64-bit kernel only:
-       select ARCH_HAS_GIGANTIC_PAGE
+       select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
        select ARCH_SUPPORTS_INT128
        select ARCH_USE_CMPXCHG_LOCKREF
        select HAVE_ARCH_SOFT_DIRTY

diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h
index 3a106165e03ad035484df5fb97989265798263df..535af0f2d8ac3059a3f700b42157f464931ad3bf 100644 (file)
--- a/arch/x86/include/asm/hugetlb.h
+++ b/arch/x86/include/asm/hugetlb.h
@@ -85,4 +85,8 @@ static inline void arch_clear_hugepage_flags(struct page *page)
 {
 }
 
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
+static inline bool gigantic_page_supported(void) { return true; }
+#endif
+
 #endif /* _ASM_X86_HUGETLB_H */

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 33263734255552911b6fb00d112c52de7be0b97a..c73828e431004c4fe0e17b1c1a73cf3d0395c7de 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1040,9 +1040,7 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
                ((node = hstate_next_node_to_free(hs, mask)) || 1);     \
                nr_nodes--)
 
-#if defined(CONFIG_ARCH_HAS_GIGANTIC_PAGE) && \
-       ((defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || \
-       defined(CONFIG_CMA))
+#ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
 static void destroy_compound_gigantic_page(struct page *page,
                                        unsigned int order)
 {
@@ -1174,8 +1172,7 @@ static int alloc_fresh_gigantic_page(struct hstate *h,
        return 0;
 }
 
-static inline bool gigantic_page_supported(void) { return true; }
-#else
+#else /* !CONFIG_ARCH_HAS_GIGANTIC_PAGE */
 static inline bool gigantic_page_supported(void) { return false; }
 static inline void free_gigantic_page(struct page *page, unsigned int order) { }
 static inline void destroy_compound_gigantic_page(struct page *page,