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| author | Vlastimil Babka <vbabka@suse.cz> | 2023-09-08 12:18:09 +0200 |
|---|---|---|
| committer | Vlastimil Babka <vbabka@suse.cz> | 2023-10-02 11:55:47 +0200 |
| commit | 90f055df112162fd9e093c16be1c21f38c35b907 (patch) | |
| tree | 323590ff68c2424b4c0ec64ca6f49c64fa7f410f /mm/slub.c | |
| parent | mm/slub: attempt to find layouts up to 1/2 waste in calculate_order() (diff) | |
| download | linux-90f055df112162fd9e093c16be1c21f38c35b907.tar.xz linux-90f055df112162fd9e093c16be1c21f38c35b907.zip | |
mm/slub: refactor calculate_order() and calc_slab_order()
After the previous cleanups, we can now move some code from
calc_slab_order() to calculate_order() so it's executed just once, and
do some more cleanups.
- move the min_order and MAX_OBJS_PER_PAGE evaluation to
calculate_order().
- change calc_slab_order() parameter min_objects to min_order
Also make MAX_OBJS_PER_PAGE check more robust by considering also
min_objects in addition to slub_min_order. Otherwise this is not a
functional change.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Feng Tang <feng.tang@intel.com>
Reviewed-and-tested-by: Jay Patel <jaypatel@linux.ibm.com>
Diffstat (limited to 'mm/slub.c')
| -rw-r--r-- | mm/slub.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/mm/slub.c b/mm/slub.c index 86141e5164ca..63d281dfacdb 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4110,17 +4110,12 @@ static unsigned int slub_min_objects; * the smallest order which will fit the object. */ static inline unsigned int calc_slab_order(unsigned int size, - unsigned int min_objects, unsigned int max_order, + unsigned int min_order, unsigned int max_order, unsigned int fract_leftover) { - unsigned int min_order = slub_min_order; unsigned int order; - if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) - return get_order(size * MAX_OBJS_PER_PAGE) - 1; - - for (order = max(min_order, (unsigned int)get_order(min_objects * size)); - order <= max_order; order++) { + for (order = min_order; order <= max_order; order++) { unsigned int slab_size = (unsigned int)PAGE_SIZE << order; unsigned int rem; @@ -4139,7 +4134,7 @@ static inline int calculate_order(unsigned int size) unsigned int order; unsigned int min_objects; unsigned int max_objects; - unsigned int nr_cpus; + unsigned int min_order; min_objects = slub_min_objects; if (!min_objects) { @@ -4152,14 +4147,20 @@ static inline int calculate_order(unsigned int size) * order on systems that appear larger than they are, and too * low order on systems that appear smaller than they are. */ - nr_cpus = num_present_cpus(); + unsigned int nr_cpus = num_present_cpus(); if (nr_cpus <= 1) nr_cpus = nr_cpu_ids; min_objects = 4 * (fls(nr_cpus) + 1); } - max_objects = order_objects(slub_max_order, size); + /* min_objects can't be 0 because get_order(0) is undefined */ + max_objects = max(order_objects(slub_max_order, size), 1U); min_objects = min(min_objects, max_objects); + min_order = max_t(unsigned int, slub_min_order, + get_order(min_objects * size)); + if (order_objects(min_order, size) > MAX_OBJS_PER_PAGE) + return get_order(size * MAX_OBJS_PER_PAGE) - 1; + /* * Attempt to find best configuration for a slab. This works by first * attempting to generate a layout with the best possible configuration @@ -4176,7 +4177,7 @@ static inline int calculate_order(unsigned int size) * long as at least single object fits within slub_max_order. */ for (unsigned int fraction = 16; fraction > 1; fraction /= 2) { - order = calc_slab_order(size, min_objects, slub_max_order, + order = calc_slab_order(size, min_order, slub_max_order, fraction); if (order <= slub_max_order) return order; |