aboutsummaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorHugh Dickins <hughd@google.com>2014-07-02 15:22:38 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-01-29 17:40:52 -0800
commit15c145c39719fbcb3818fbc0df843f7263bbbe89 (patch)
treeed2b377a016df25908cca83d8939c404a8f3ca1f /mm
parent07e97c1e9bb85706d84395aa46d47c8ae5ff3e0f (diff)
shmem: fix init_page_accessed use to stop !PageLRU bug
commit 66d2f4d28cd030220e7ea2a628993fcabcb956d1 upstream. Under shmem swapping load, I sometimes hit the VM_BUG_ON_PAGE(!PageLRU) in isolate_lru_pages() at mm/vmscan.c:1281! Commit 2457aec63745 ("mm: non-atomically mark page accessed during page cache allocation where possible") looks like interrupted work-in-progress. mm/filemap.c's call to init_page_accessed() is fine, but not mm/shmem.c's - shmem_write_begin() is clearly wrong to use it after shmem_getpage(), when the page is always visible in radix_tree, and often already on LRU. Revert change to shmem_write_begin(), and use init_page_accessed() or mark_page_accessed() appropriately for SGP_WRITE in shmem_getpage_gfp(). SGP_WRITE also covers shmem_symlink(), which did not mark_page_accessed() before; but since many other filesystems use [__]page_symlink(), which did and does mark the page accessed, consider this as rectifying an oversight. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Prabhakar Lad <prabhakar.csengg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/shmem.c15
1 files changed, 10 insertions, 5 deletions
diff --git a/mm/shmem.c b/mm/shmem.c
index fe1c488012bc..85d8a1a3626c 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1035,6 +1035,9 @@ repeat:
goto failed;
}
+ if (page && sgp == SGP_WRITE)
+ mark_page_accessed(page);
+
/* fallocated page? */
if (page && !PageUptodate(page)) {
if (sgp != SGP_READ)
@@ -1116,6 +1119,9 @@ repeat:
shmem_recalc_inode(inode);
spin_unlock(&info->lock);
+ if (sgp == SGP_WRITE)
+ mark_page_accessed(page);
+
delete_from_swap_cache(page);
set_page_dirty(page);
swap_free(swap);
@@ -1142,6 +1148,9 @@ repeat:
__SetPageSwapBacked(page);
__set_page_locked(page);
+ if (sgp == SGP_WRITE)
+ init_page_accessed(page);
+
error = mem_cgroup_cache_charge(page, current->mm,
gfp & GFP_RECLAIM_MASK);
if (error)
@@ -1438,13 +1447,9 @@ shmem_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
- int ret;
struct inode *inode = mapping->host;
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
- ret = shmem_getpage(inode, index, pagep, SGP_WRITE, NULL);
- if (ret == 0 && *pagep)
- init_page_accessed(*pagep);
- return ret;
+ return shmem_getpage(inode, index, pagep, SGP_WRITE, NULL);
}
static int