From fa48e6f780a681cdbc7820e33259edfe1a79b9e3 Mon Sep 17 00:00:00 2001
From: Steve Capper <steve.capper@linaro.org>
Date: Fri, 2 May 2014 14:49:00 +0100
Subject: [PATCH] arm64: mm: Optimise tlb flush logic where we have >4K granule
The tlb maintainence functions: __cpu_flush_user_tlb_range and
__cpu_flush_kern_tlb_range do not take into consideration the page
granule when looping through the address range, and repeatedly flush
tlb entries for the same page when operating with 64K pages.
This patch re-works the logic s.t. we instead advance the loop by
1 << (PAGE_SHIFT - 12), so avoid repeating ourselves.
Also the routines have been converted from assembler to static inline
functions to aid with legibility and potential compiler optimisations.
The isb() has been removed from flush_tlb_kernel_range(.) as it is
only needed when changing the execute permission of a mapping. If one
needs to set an area of the kernel as execute/non-execute an isb()
must be inserted after the call to flush_tlb_kernel_range.
Cc: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---
arch/arm64/include/asm/tlbflush.h | 30 ++++++++++---
arch/arm64/mm/Makefile | 2 +-
arch/arm64/mm/tlb.S | 71 -------------------------------
3 files changed, 26 insertions(+), 77 deletions(-)
delete mode 100644 arch/arm64/mm/tlb.S
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 8b482035cfc24..7881d7dbb9ba3 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -98,11 +98,31 @@ static inline void flush_tlb_page(struct vm_area_struct *vma,
dsb();
}
-/*
- * Convert calls to our calling convention.
- */
-#define flush_tlb_range(vma,start,end) __cpu_flush_user_tlb_range(start,end,vma)
-#define flush_tlb_kernel_range(s,e) __cpu_flush_kern_tlb_range(s,e)
+static inline void flush_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ unsigned long asid = (unsigned long)ASID(vma->vm_mm) << 48;
+ unsigned long addr;
+ start = asid | (start >> 12);
+ end = asid | (end >> 12);
+
+ dsb(ishst);
+ for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
+ asm("tlbi vae1is, %0" : : "r"(addr));
+ dsb(ish);
+}
+
+static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+ start >>= 12;
+ end >>= 12;
+
+ dsb(ishst);
+ for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
+ asm("tlbi vaae1is, %0" : : "r"(addr));
+ dsb(ish);
+}
/*
* On AArch64, the cache coherency is handled via the set_pte_at() function.
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index b51d36401d83f..3ecb56c624d36 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -1,5 +1,5 @@
obj-y := dma-mapping.o extable.o fault.o init.o \
cache.o copypage.o flush.o \
ioremap.o mmap.o pgd.o mmu.o \
- context.o tlb.o proc.o
+ context.o proc.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/arm64/mm/tlb.S b/arch/arm64/mm/tlb.S
deleted file mode 100644
index 19da91e0cd278..0000000000000
--- a/arch/arm64/mm/tlb.S
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * Based on arch/arm/mm/tlb.S
- *
- * Copyright (C) 1997-2002 Russell King
- * Copyright (C) 2012 ARM Ltd.
- * Written by Catalin Marinas <catalin.marinas@arm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-#include <linux/linkage.h>
-#include <asm/assembler.h>
-#include <asm/asm-offsets.h>
-#include <asm/page.h>
-#include <asm/tlbflush.h>
-#include "proc-macros.S"
-
-/*
- * __cpu_flush_user_tlb_range(start, end, vma)
- *
- * Invalidate a range of TLB entries in the specified address space.
- *
- * - start - start address (may not be aligned)
- * - end - end address (exclusive, may not be aligned)
- * - vma - vma_struct describing address range
- */
-ENTRY(__cpu_flush_user_tlb_range)
- vma_vm_mm x3, x2 // get vma->vm_mm
- mmid w3, x3 // get vm_mm->context.id
- dsb sy
- lsr x0, x0, #12 // align address
- lsr x1, x1, #12
- bfi x0, x3, #48, #16 // start VA and ASID
- bfi x1, x3, #48, #16 // end VA and ASID
-1: tlbi vae1is, x0 // TLB invalidate by address and ASID
- add x0, x0, #1
- cmp x0, x1
- b.lo 1b
- dsb sy
- ret
-ENDPROC(__cpu_flush_user_tlb_range)
-
-/*
- * __cpu_flush_kern_tlb_range(start,end)
- *
- * Invalidate a range of kernel TLB entries.
- *
- * - start - start address (may not be aligned)
- * - end - end address (exclusive, may not be aligned)
- */
-ENTRY(__cpu_flush_kern_tlb_range)
- dsb sy
- lsr x0, x0, #12 // align address
- lsr x1, x1, #12
-1: tlbi vaae1is, x0 // TLB invalidate by address
- add x0, x0, #1
- cmp x0, x1
- b.lo 1b
- dsb sy
- isb
- ret
-ENDPROC(__cpu_flush_kern_tlb_range)
--
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