diff options
| author |   Joonsoo Kim <iamjoonsoo.kim@lge.com> | 2016-05-19 17:10:49 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-19 19:12:14 -0700 |
| commit | 0139aa7b7fa12ceef095d99dc36606a5b10ab83a (patch) | |
| tree | 94da74f2f79911a11a3c7c34f73ba971dec41a7e /mm/vmscan.c | |
| parent | mm/page_ref: use page_ref helper instead of direct modification of _count (diff) | |
| download | linux-dev-0139aa7b7fa12ceef095d99dc36606a5b10ab83a.tar.xz linux-dev-0139aa7b7fa12ceef095d99dc36606a5b10ab83a.zip | |
mm: rename _count, field of the struct page, to _refcount
Many developers already know that field for reference count of the
struct page is _count and atomic type. They would try to handle it
directly and this could break the purpose of page reference count
tracepoint. To prevent direct _count modification, this patch rename it
to _refcount and add warning message on the code. After that, developer
who need to handle reference count will find that field should not be
accessed directly.
[akpm@linux-foundation.org: fix comments, per Vlastimil]
[akpm@linux-foundation.org: Documentation/vm/transhuge.txt too]
[sfr@canb.auug.org.au: sync ethernet driver changes]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Sunil Goutham <sgoutham@cavium.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Manish Chopra <manish.chopra@qlogic.com>
Cc: Yuval Mintz <yuval.mintz@qlogic.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 142cb61f4822..d3a02ac3eed7 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -633,7 +633,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, * * Reversing the order of the tests ensures such a situation cannot * escape unnoticed. The smp_rmb is needed to ensure the page->flags - * load is not satisfied before that of page->_count. + * load is not satisfied before that of page->_refcount. * * Note that if SetPageDirty is always performed via set_page_dirty, * and thus under tree_lock, then this ordering is not required. @@ -1720,7 +1720,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, * It is safe to rely on PG_active against the non-LRU pages in here because * nobody will play with that bit on a non-LRU page. * - * The downside is that we have to touch page->_count against each page. + * The downside is that we have to touch page->_refcount against each page. * But we had to alter page->flags anyway. */ |