diff options
| -rw-r--r-- | mm/slab.c | 89 |
1 files changed, 49 insertions, 40 deletions
diff --git a/mm/slab.c b/mm/slab.c index 3d3b5a46854..2551b1eeadb 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1474,6 +1474,53 @@ static inline void set_up_list3s(kmem_cache_t *cachep, int index) } /** + * calculate_slab_order - calculate size (page order) of slabs and the number + * of objects per slab. + * + * This could be made much more intelligent. For now, try to avoid using + * high order pages for slabs. When the gfp() functions are more friendly + * towards high-order requests, this should be changed. + */ +static inline size_t calculate_slab_order(kmem_cache_t *cachep, size_t size, + size_t align, gfp_t flags) +{ + size_t left_over = 0; + + for ( ; ; cachep->gfporder++) { + unsigned int num; + size_t remainder; + + if (cachep->gfporder > MAX_GFP_ORDER) { + cachep->num = 0; + break; + } + + cache_estimate(cachep->gfporder, size, align, flags, + &remainder, &num); + if (!num) + continue; + /* More than offslab_limit objects will cause problems */ + if (flags & CFLGS_OFF_SLAB && cachep->num > offslab_limit) + break; + + cachep->num = num; + left_over = remainder; + + /* + * Large number of objects is good, but very large slabs are + * currently bad for the gfp()s. + */ + if (cachep->gfporder >= slab_break_gfp_order) + break; + + if ((left_over * 8) <= (PAGE_SIZE << cachep->gfporder)) + /* Acceptable internal fragmentation */ + break; + } + return left_over; +} + +/** * kmem_cache_create - Create a cache. * @name: A string which is used in /proc/slabinfo to identify this cache. * @size: The size of objects to be created in this cache. @@ -1682,46 +1729,8 @@ kmem_cache_create (const char *name, size_t size, size_t align, cachep->gfporder = 0; cache_estimate(cachep->gfporder, size, align, flags, &left_over, &cachep->num); - } else { - /* - * Calculate size (in pages) of slabs, and the num of objs per - * slab. This could be made much more intelligent. For now, - * try to avoid using high page-orders for slabs. When the - * gfp() funcs are more friendly towards high-order requests, - * this should be changed. - */ - do { - unsigned int break_flag = 0; -cal_wastage: - cache_estimate(cachep->gfporder, size, align, flags, - &left_over, &cachep->num); - if (break_flag) - break; - if (cachep->gfporder >= MAX_GFP_ORDER) - break; - if (!cachep->num) - goto next; - if (flags & CFLGS_OFF_SLAB && - cachep->num > offslab_limit) { - /* This num of objs will cause problems. */ - cachep->gfporder--; - break_flag++; - goto cal_wastage; - } - - /* - * Large num of objs is good, but v. large slabs are - * currently bad for the gfp()s. - */ - if (cachep->gfporder >= slab_break_gfp_order) - break; - - if ((left_over*8) <= (PAGE_SIZE<<cachep->gfporder)) - break; /* Acceptable internal fragmentation. */ -next: - cachep->gfporder++; - } while (1); - } + } else + left_over = calculate_slab_order(cachep, size, align, flags); if (!cachep->num) { printk("kmem_cache_create: couldn't create cache %s.\n", name); |