[PATCH v3 3/4] hugetlbfs: remove hugetlb_add_hstate() warning for existing hstate

[Mike Kravetz]

The routine hugetlb_add_hstate prints a warning if the hstate already
exists.  This was originally done as part of kernel command line
parsing.  If 'hugepagesz=' was specified more than once, the warning
	pr_warn("hugepagesz= specified twice, ignoring\n");
would be printed.

Some architectures want to enable all huge page sizes.  They would
call hugetlb_add_hstate for all supported sizes.  However, this was
done after command line processing and as a result hstates could have
already been created for some sizes.  To make sure no warning were
printed, there would often be code like:
	if (!size_to_hstate(size)
		hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT)

The only time we want to print the warning is as the result of command
line processing.  So, remove the warning from hugetlb_add_hstate and
add it to the single arch independent routine processing "hugepagesz=".
After this, calls to size_to_hstate() in arch specific code can be
removed and hugetlb_add_hstate can be called without worrying about
warning messages.

Signed-off-by: Mike Kravetz <mike.kravetz at oracle.com>
Acked-by: Mina Almasry <almasrymina at google.com>
---
 arch/arm64/mm/hugetlbpage.c   | 16 ++++------------
 arch/powerpc/mm/hugetlbpage.c |  3 +--
 arch/riscv/mm/hugetlbpage.c   |  2 +-
 arch/sparc/mm/init_64.c       | 19 ++++---------------
 arch/x86/mm/hugetlbpage.c     |  2 +-
 mm/hugetlb.c                  |  9 ++++++---
 6 files changed, 17 insertions(+), 34 deletions(-)

diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index f706b821aba6..21fa98b51e00 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -441,22 +441,14 @@ void huge_ptep_clear_flush(struct vm_area_struct *vma,
 	clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
 }
 
-static void __init add_huge_page_size(unsigned long size)
-{
-	if (size_to_hstate(size))
-		return;
-
-	hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT);
-}
-
 static int __init hugetlbpage_init(void)
 {
 #ifdef CONFIG_ARM64_4K_PAGES
-	add_huge_page_size(PUD_SIZE);
+	hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
 #endif
-	add_huge_page_size(CONT_PMD_SIZE);
-	add_huge_page_size(PMD_SIZE);
-	add_huge_page_size(CONT_PTE_SIZE);
+	hugetlb_add_hstate(CONT_PMD_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(CONT_PTE_SHIFT - PAGE_SHIFT);
 
 	return 0;
 }
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index 2c3fa0a7787b..4d5ed1093615 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -584,8 +584,7 @@ static int __init add_huge_page_size(unsigned long long size)
 	if (!arch_hugetlb_valid_size((unsigned long)size))
 		return -EINVAL;
 
-	if (!size_to_hstate(size))
-		hugetlb_add_hstate(shift - PAGE_SHIFT);
+	hugetlb_add_hstate(shift - PAGE_SHIFT);
 	return 0;
 }
 
diff --git a/arch/riscv/mm/hugetlbpage.c b/arch/riscv/mm/hugetlbpage.c
index 4e5d7e9f0eef..932dadfdca54 100644
--- a/arch/riscv/mm/hugetlbpage.c
+++ b/arch/riscv/mm/hugetlbpage.c
@@ -26,7 +26,7 @@ bool __init arch_hugetlb_valid_size(unsigned long size)
 static __init int gigantic_pages_init(void)
 {
 	/* With CONTIG_ALLOC, we can allocate gigantic pages at runtime */
-	if (IS_ENABLED(CONFIG_64BIT) && !size_to_hstate(1UL << PUD_SHIFT))
+	if (IS_ENABLED(CONFIG_64BIT))
 		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
 	return 0;
 }
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 4618f96fd30f..ae819a16d07a 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -325,23 +325,12 @@ static void __update_mmu_tsb_insert(struct mm_struct *mm, unsigned long tsb_inde
 }
 
 #ifdef CONFIG_HUGETLB_PAGE
-static void __init add_huge_page_size(unsigned long size)
-{
-	unsigned int order;
-
-	if (size_to_hstate(size))
-		return;
-
-	order = ilog2(size) - PAGE_SHIFT;
-	hugetlb_add_hstate(order);
-}
-
 static int __init hugetlbpage_init(void)
 {
-	add_huge_page_size(1UL << HPAGE_64K_SHIFT);
-	add_huge_page_size(1UL << HPAGE_SHIFT);
-	add_huge_page_size(1UL << HPAGE_256MB_SHIFT);
-	add_huge_page_size(1UL << HPAGE_2GB_SHIFT);
+	hugetlb_add_hstate(HPAGE_64K_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(HPAGE_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(HPAGE_256MB_SHIFT - PAGE_SHIFT);
+	hugetlb_add_hstate(HPAGE_2GB_SHIFT - PAGE_SHIFT);
 
 	return 0;
 }
diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c
index 937d640a89e3..cf5781142716 100644
--- a/arch/x86/mm/hugetlbpage.c
+++ b/arch/x86/mm/hugetlbpage.c
@@ -195,7 +195,7 @@ bool __init arch_hugetlb_valid_size(unsigned long size)
 static __init int gigantic_pages_init(void)
 {
 	/* With compaction or CMA we can allocate gigantic pages at runtime */
-	if (boot_cpu_has(X86_FEATURE_GBPAGES) && !size_to_hstate(1UL << PUD_SHIFT))
+	if (boot_cpu_has(X86_FEATURE_GBPAGES))
 		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
 	return 0;
 }
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b2d276408cec..0e6eb755ae94 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3222,8 +3222,7 @@ static int __init hugetlb_init(void)
 		}
 
 		default_hstate_size = HPAGE_SIZE;
-		if (!size_to_hstate(default_hstate_size))
-			hugetlb_add_hstate(HUGETLB_PAGE_ORDER);
+		hugetlb_add_hstate(HUGETLB_PAGE_ORDER);
 	}
 	default_hstate_idx = hstate_index(size_to_hstate(default_hstate_size));
 	if (default_hstate_max_huge_pages) {
@@ -3268,7 +3267,6 @@ void __init hugetlb_add_hstate(unsigned int order)
 	unsigned long i;
 
 	if (size_to_hstate(PAGE_SIZE << order)) {
-		pr_warn("hugepagesz= specified twice, ignoring\n");
 		return;
 	}
 	BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE);
@@ -3343,6 +3341,11 @@ static int __init hugepagesz_setup(char *s)
 		return 0;
 	}
 
+	if (size_to_hstate(size)) {
+		pr_warn("HugeTLB: hugepagesz %s specified twice, ignoring\n", s);
+		return 0;
+	}
+
 	hugetlb_add_hstate(ilog2(size) - PAGE_SHIFT);
 	return 1;
 }
-- 
2.25.2