mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-15 23:14:31 +08:00
29e5694054
Activate the RCU fast_gup for ARM64. We also need to force THP splits to broadcast an IPI s.t. we block in the fast_gup page walker. As THP splits are comparatively rare, this should not lead to a noticeable performance degradation. Some pre-requisite functions pud_write and pud_page are also added. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Steve Capper <steve.capper@linaro.org> Tested-by: Dann Frazier <dann.frazier@canonical.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Hugh Dickins <hughd@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
123 lines
3.2 KiB
C
123 lines
3.2 KiB
C
/*
|
|
* Based on arch/arm/mm/flush.c
|
|
*
|
|
* Copyright (C) 1995-2002 Russell King
|
|
* Copyright (C) 2012 ARM Ltd.
|
|
*
|
|
* 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/export.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/pagemap.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/cachetype.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
#include "mm.h"
|
|
|
|
void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
if (vma->vm_flags & VM_EXEC)
|
|
__flush_icache_all();
|
|
}
|
|
|
|
static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
|
|
unsigned long uaddr, void *kaddr,
|
|
unsigned long len)
|
|
{
|
|
if (vma->vm_flags & VM_EXEC) {
|
|
unsigned long addr = (unsigned long)kaddr;
|
|
if (icache_is_aliasing()) {
|
|
__flush_dcache_area(kaddr, len);
|
|
__flush_icache_all();
|
|
} else {
|
|
flush_icache_range(addr, addr + len);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Copy user data from/to a page which is mapped into a different processes
|
|
* address space. Really, we want to allow our "user space" model to handle
|
|
* this.
|
|
*
|
|
* Note that this code needs to run on the current CPU.
|
|
*/
|
|
void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
|
|
unsigned long uaddr, void *dst, const void *src,
|
|
unsigned long len)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
preempt_disable();
|
|
#endif
|
|
memcpy(dst, src, len);
|
|
flush_ptrace_access(vma, page, uaddr, dst, len);
|
|
#ifdef CONFIG_SMP
|
|
preempt_enable();
|
|
#endif
|
|
}
|
|
|
|
void __sync_icache_dcache(pte_t pte, unsigned long addr)
|
|
{
|
|
struct page *page = pte_page(pte);
|
|
|
|
/* no flushing needed for anonymous pages */
|
|
if (!page_mapping(page))
|
|
return;
|
|
|
|
if (!test_and_set_bit(PG_dcache_clean, &page->flags)) {
|
|
__flush_dcache_area(page_address(page),
|
|
PAGE_SIZE << compound_order(page));
|
|
__flush_icache_all();
|
|
} else if (icache_is_aivivt()) {
|
|
__flush_icache_all();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function is called when a page has been modified by the kernel. Mark
|
|
* it as dirty for later flushing when mapped in user space (if executable,
|
|
* see __sync_icache_dcache).
|
|
*/
|
|
void flush_dcache_page(struct page *page)
|
|
{
|
|
if (test_bit(PG_dcache_clean, &page->flags))
|
|
clear_bit(PG_dcache_clean, &page->flags);
|
|
}
|
|
EXPORT_SYMBOL(flush_dcache_page);
|
|
|
|
/*
|
|
* Additional functions defined in assembly.
|
|
*/
|
|
EXPORT_SYMBOL(flush_cache_all);
|
|
EXPORT_SYMBOL(flush_icache_range);
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
#ifdef CONFIG_HAVE_RCU_TABLE_FREE
|
|
void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
|
|
pmd_t *pmdp)
|
|
{
|
|
pmd_t pmd = pmd_mksplitting(*pmdp);
|
|
|
|
VM_BUG_ON(address & ~PMD_MASK);
|
|
set_pmd_at(vma->vm_mm, address, pmdp, pmd);
|
|
|
|
/* dummy IPI to serialise against fast_gup */
|
|
kick_all_cpus_sync();
|
|
}
|
|
#endif /* CONFIG_HAVE_RCU_TABLE_FREE */
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|