path: root/mm/memory.c
diff options
authorJoel Fernandes (Google) <joel@joelfernandes.org>2019-01-03 15:28:34 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2019-01-04 13:13:47 -0800
commit4cf58924951ef80eec636b863e7a53973c44261a (patch)
tree388816f0df0547713a1977d3aa8f120065822487 /mm/memory.c
parentinitramfs: cleanup incomplete rootfs (diff)
mm: treewide: remove unused address argument from pte_alloc functions
Patch series "Add support for fast mremap". This series speeds up the mremap(2) syscall by copying page tables at the PMD level even for non-THP systems. There is concern that the extra 'address' argument that mremap passes to pte_alloc may do something subtle architecture related in the future that may make the scheme not work. Also we find that there is no point in passing the 'address' to pte_alloc since its unused. This patch therefore removes this argument tree-wide resulting in a nice negative diff as well. Also ensuring along the way that the enabled architectures do not do anything funky with the 'address' argument that goes unnoticed by the optimization. Build and boot tested on x86-64. Build tested on arm64. The config enablement patch for arm64 will be posted in the future after more testing. The changes were obtained by applying the following Coccinelle script. (thanks Julia for answering all Coccinelle questions!). Following fix ups were done manually: * Removal of address argument from pte_fragment_alloc * Removal of pte_alloc_one_fast definitions from m68k and microblaze. // Options: --include-headers --no-includes // Note: I split the 'identifier fn' line, so if you are manually // running it, please unsplit it so it runs for you. virtual patch @pte_alloc_func_def depends on patch exists@ identifier E2; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; type T2; @@ fn(... - , T2 E2 ) { ... } @pte_alloc_func_proto_noarg depends on patch exists@ type T1, T2, T3, T4; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ ( - T3 fn(T1, T2); + T3 fn(T1); | - T3 fn(T1, T2, T4); + T3 fn(T1, T2); ) @pte_alloc_func_proto depends on patch exists@ identifier E1, E2, E4; type T1, T2, T3, T4; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ ( - T3 fn(T1 E1, T2 E2); + T3 fn(T1 E1); | - T3 fn(T1 E1, T2 E2, T4 E4); + T3 fn(T1 E1, T2 E2); ) @pte_alloc_func_call depends on patch exists@ expression E2; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ fn(... -, E2 ) @pte_alloc_macro depends on patch exists@ identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; identifier a, b, c; expression e; position p; @@ ( - #define fn(a, b, c) e + #define fn(a, b) e | - #define fn(a, b) e + #define fn(a) e ) Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Suggested-by: Kirill A. Shutemov <kirill@shutemov.name> Acked-by: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michal Hocko <mhocko@kernel.org> Cc: Julia Lawall <Julia.Lawall@lip6.fr> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
1 files changed, 8 insertions, 9 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 2dd2f9ab57f4..a52663c0612d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -400,10 +400,10 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
-int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
+int __pte_alloc(struct mm_struct *mm, pmd_t *pmd)
spinlock_t *ptl;
- pgtable_t new = pte_alloc_one(mm, address);
+ pgtable_t new = pte_alloc_one(mm);
if (!new)
return -ENOMEM;
@@ -434,9 +434,9 @@ int __pte_alloc(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
return 0;
-int __pte_alloc_kernel(pmd_t *pmd, unsigned long address)
+int __pte_alloc_kernel(pmd_t *pmd)
- pte_t *new = pte_alloc_one_kernel(&init_mm, address);
+ pte_t *new = pte_alloc_one_kernel(&init_mm);
if (!new)
return -ENOMEM;
@@ -2896,7 +2896,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
* Here we only have down_read(mmap_sem).
- if (pte_alloc(vma->vm_mm, vmf->pmd, vmf->address))
+ if (pte_alloc(vma->vm_mm, vmf->pmd))
return VM_FAULT_OOM;
/* See the comment in pte_alloc_one_map() */
@@ -3043,7 +3043,7 @@ static vm_fault_t pte_alloc_one_map(struct vm_fault *vmf)
pmd_populate(vma->vm_mm, vmf->pmd, vmf->prealloc_pte);
vmf->prealloc_pte = NULL;
- } else if (unlikely(pte_alloc(vma->vm_mm, vmf->pmd, vmf->address))) {
+ } else if (unlikely(pte_alloc(vma->vm_mm, vmf->pmd))) {
return VM_FAULT_OOM;
@@ -3122,7 +3122,7 @@ static vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
* related to pte entry. Use the preallocated table for that.
if (arch_needs_pgtable_deposit() && !vmf->prealloc_pte) {
- vmf->prealloc_pte = pte_alloc_one(vma->vm_mm, vmf->address);
+ vmf->prealloc_pte = pte_alloc_one(vma->vm_mm);
if (!vmf->prealloc_pte)
return VM_FAULT_OOM;
smp_wmb(); /* See comment in __pte_alloc() */
@@ -3360,8 +3360,7 @@ static vm_fault_t do_fault_around(struct vm_fault *vmf)
start_pgoff + nr_pages - 1);
if (pmd_none(*vmf->pmd)) {
- vmf->prealloc_pte = pte_alloc_one(vmf->vma->vm_mm,
- vmf->address);
+ vmf->prealloc_pte = pte_alloc_one(vmf->vma->vm_mm);
if (!vmf->prealloc_pte)
goto out;
smp_wmb(); /* See comment in __pte_alloc() */