diff options
author | Kent Overstreet <kent.overstreet@linux.dev> | 2024-03-02 13:27:50 -0500 |
---|---|---|
committer | Kent Overstreet <kent.overstreet@linux.dev> | 2024-03-07 23:18:26 -0500 |
commit | 77fcd88de2ae1309c16e4fc35fb90cbc60c3d2ec (patch) | |
tree | f8ba44500c7d06eed1f3c4794759b4226d6a7c09 | |
parent | 1054c0f498fcb57de4858313d974aee23daf7376 (diff) |
mm/slub: Make __ksize() fastervmalloc_size
with slab gone, we now have a free u32 in struct slab.
This steals it to make __ksize() faster; it's now a single dependent
load, instead of two. This is going to be important for tracking the
amount of memory stranded by RCU, which we want to be able to do if
we're going to be freeing all pagecache folios (and perhaps all folios)
via RCU.
Cc: linux-mm@kvack.org
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
-rw-r--r-- | mm/slab.h | 2 | ||||
-rw-r--r-- | mm/slab_common.c | 9 | ||||
-rw-r--r-- | mm/slub.c | 2 |
3 files changed, 7 insertions, 6 deletions
diff --git a/mm/slab.h b/mm/slab.h index 54deeb0428c6..64f06431cc97 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -84,7 +84,7 @@ struct slab { }; struct rcu_head rcu_head; }; - unsigned int __unused; + unsigned int object_size; atomic_t __page_refcount; #ifdef CONFIG_MEMCG diff --git a/mm/slab_common.c b/mm/slab_common.c index 6ec0f6543f34..f209b8cf4965 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -963,13 +963,12 @@ size_t __ksize(const void *object) if (WARN_ON(object != folio_address(folio))) return 0; return folio_size(folio); - } - + } else { #ifdef CONFIG_SLUB_DEBUG - skip_orig_size_check(folio_slab(folio)->slab_cache, object); + skip_orig_size_check(folio_slab(folio)->slab_cache, object); #endif - - return slab_ksize(folio_slab(folio)->slab_cache); + return folio_slab(folio)->object_size; + } } /** diff --git a/mm/slub.c b/mm/slub.c index 2ef88bbf56a3..45e95133653e 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2366,6 +2366,7 @@ static struct slab *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) } slab->objects = oo_objects(oo); + slab->object_size = slab_ksize(s); slab->inuse = 0; slab->frozen = 0; @@ -2414,6 +2415,7 @@ static void __free_slab(struct kmem_cache *s, struct slab *slab) int order = folio_order(folio); int pages = 1 << order; + slab->object_size = -1; /* page->_mapcount */ __slab_clear_pfmemalloc(slab); folio->mapping = NULL; /* Make the mapping reset visible before clearing the flag */ |