diff options
| author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-07-24 19:54:08 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-18 10:12:52 -0700 |
| commit | f5617ffeb450f84c57f7eba1a3524a29955d42b7 (patch) | |
| tree | 74d1b0c1d61e71d0500fd658645b662277a8bc6d /mm/memory.c | |
| parent | 61a4b8d32025dcabcd78994f887a4b9dff912cf0 (diff) | |
mm: run the fault-around code under the VMA lock
The map_pages fs method should be safe to run under the VMA lock instead
of the mmap lock. This should have a measurable reduction in contention
on the mmap lock.
Link: https://lkml.kernel.org/r/20230724185410.1124082-9-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 | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/memory.c b/mm/memory.c index 23a20b7a483c..52235aa3d665 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4533,11 +4533,6 @@ 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 @@ -4549,6 +4544,11 @@ static vm_fault_t do_read_fault(struct vm_fault *vmf) return ret; } + if (vmf->flags & FAULT_FLAG_VMA_LOCK) { + vma_end_read(vmf->vma); + return VM_FAULT_RETRY; + } + ret = __do_fault(vmf); if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY))) return ret; |