diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-07-24 19:54:07 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 10:12:52 -0700 |
| commit | 61a4b8d32025dcabcd78994f887a4b9dff912cf0 (patch) | |
| tree | d7a63526535a910cf153bb611a28d51795760c87 /mm/memory.c | |
| parent | 0c2e394ab23017303f676e6206a54c54bb0e3681 (diff) | |
| download | lwn-61a4b8d32025dcabcd78994f887a4b9dff912cf0.tar.gz lwn-61a4b8d32025dcabcd78994f887a4b9dff912cf0.zip | |
mm: move FAULT_FLAG_VMA_LOCK check down from do_fault()
Perform the check at the start of do_read_fault(), do_cow_fault() and
do_shared_fault() instead. Should be no performance change from the last
commit.
Link: https://lkml.kernel.org/r/20230724185410.1124082-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Arjun Roy <arjunroy@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Punit Agrawal <punit.agrawal@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/mm/memory.c b/mm/memory.c index d947d8d9e891..23a20b7a483c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4533,6 +4533,11 @@ static vm_fault_t do_read_fault(struct vm_fault *vmf) vm_fault_t ret = 0; struct folio *folio; + if (vmf->flags & FAULT_FLAG_VMA_LOCK) { + vma_end_read(vmf->vma); + return VM_FAULT_RETRY; + } + /* * Let's call ->map_pages() first and use ->fault() as fallback * if page by the offset is not ready to be mapped (cold cache or @@ -4561,6 +4566,11 @@ static vm_fault_t do_cow_fault(struct vm_fault *vmf) struct vm_area_struct *vma = vmf->vma; vm_fault_t ret; + if (vmf->flags & FAULT_FLAG_VMA_LOCK) { + vma_end_read(vma); + return VM_FAULT_RETRY; + } + if (unlikely(anon_vma_prepare(vma))) return VM_FAULT_OOM; @@ -4601,6 +4611,11 @@ static vm_fault_t do_shared_fault(struct vm_fault *vmf) vm_fault_t ret, tmp; struct folio *folio; + if (vmf->flags & FAULT_FLAG_VMA_LOCK) { + vma_end_read(vma); + return VM_FAULT_RETRY; + } + ret = __do_fault(vmf); if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) return ret; @@ -4647,11 +4662,6 @@ static vm_fault_t do_fault(struct vm_fault *vmf) struct mm_struct *vm_mm = vma->vm_mm; vm_fault_t ret; - if (vmf->flags & FAULT_FLAG_VMA_LOCK){ - vma_end_read(vma); - return VM_FAULT_RETRY; - } - /* * The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */ |