mm: memcg: handle non-error OOM situations more gracefully

[~andy/linux] / mm / filemap.c

diff --git a/mm/filemap.c b/mm/filemap.c
index 1e6aec4a2d2ebae29c0fea0405a7e81f422beeb4..ae4846ff48494e9ac5e733a5d5339b61763a49f5 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1616,7 +1616,6 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
        struct inode *inode = mapping->host;
        pgoff_t offset = vmf->pgoff;
        struct page *page;
-       bool memcg_oom;
        pgoff_t size;
        int ret = 0;
 
@@ -1625,11 +1624,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                return VM_FAULT_SIGBUS;
 
        /*
-        * Do we have something in the page cache already?  Either
-        * way, try readahead, but disable the memcg OOM killer for it
-        * as readahead is optional and no errors are propagated up
-        * the fault stack.  The OOM killer is enabled while trying to
-        * instantiate the faulting page individually below.
+        * Do we have something in the page cache already?
         */
        page = find_get_page(mapping, offset);
        if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) {
@@ -1637,14 +1632,10 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                 * We found the page, so try async readahead before
                 * waiting for the lock.
                 */
-               memcg_oom = mem_cgroup_toggle_oom(false);
                do_async_mmap_readahead(vma, ra, file, page, offset);
-               mem_cgroup_toggle_oom(memcg_oom);
        } else if (!page) {
                /* No page in the page cache at all */
-               memcg_oom = mem_cgroup_toggle_oom(false);
                do_sync_mmap_readahead(vma, ra, file, offset);
-               mem_cgroup_toggle_oom(memcg_oom);
                count_vm_event(PGMAJFAULT);
                mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT);
                ret = VM_FAULT_MAJOR;