diff options
| author | Matthew Wilcox <mawilcox@microsoft.com> | 2018-06-07 17:08:31 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-07 17:34:37 -0700 |
| commit | 7d27a04bb2b5bd665f147439d18ae236080eef32 (patch) | |
| tree | 2798e10870a5932a694807b58215da370d1efb06 /mm | |
| parent | d4fc5069a39405d67937b25c0dc9249a9b6c50f1 (diff) | |
mm: move 'private' union within struct page
By moving page->private to the fourth word of struct page, we can put the
SLUB counters in the same word as SLAB's s_mem and still do the
cmpxchg_double trick. Now the SLUB counters no longer overlap with the
mapcount or refcount so we can drop the call to page_mapcount_reset() and
simplify set_page_slub_counters() to a single line.
Link: http://lkml.kernel.org/r/20180518194519.3820-6-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slub.c | 20 |
1 files changed, 2 insertions, 18 deletions
diff --git a/mm/slub.c b/mm/slub.c index 0170ea8a97fe..f5db87839ab4 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -356,21 +356,6 @@ static __always_inline void slab_unlock(struct page *page) __bit_spin_unlock(PG_locked, &page->flags); } -static inline void set_page_slub_counters(struct page *page, unsigned long counters_new) -{ - struct page tmp; - tmp.counters = counters_new; - /* - * page->counters can cover frozen/inuse/objects as well - * as page->_refcount. If we assign to ->counters directly - * we run the risk of losing updates to page->_refcount, so - * be careful and only assign to the fields we need. - */ - page->frozen = tmp.frozen; - page->inuse = tmp.inuse; - page->objects = tmp.objects; -} - /* Interrupts must be disabled (for the fallback code to work right) */ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page, void *freelist_old, unsigned long counters_old, @@ -392,7 +377,7 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - set_page_slub_counters(page, counters_new); + page->counters = counters_new; slab_unlock(page); return true; } @@ -431,7 +416,7 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page, if (page->freelist == freelist_old && page->counters == counters_old) { page->freelist = freelist_new; - set_page_slub_counters(page, counters_new); + page->counters = counters_new; slab_unlock(page); local_irq_restore(flags); return true; @@ -1694,7 +1679,6 @@ static void __free_slab(struct kmem_cache *s, struct page *page) __ClearPageSlabPfmemalloc(page); __ClearPageSlab(page); - page_mapcount_reset(page); page->mapping = NULL; if (current->reclaim_state) current->reclaim_state->reclaimed_slab += pages; |