diff options
| author | Christoph Lameter <clameter@sgi.com> | 2008-04-14 19:11:41 +0300 |
|---|---|---|
| committer | Pekka Enberg <penberg@cs.helsinki.fi> | 2008-04-27 18:28:18 +0300 |
| commit | 06b285dc3d6194abe79ab9dcaaab703d6f75627c (patch) | |
| tree | 4443514e99740054028f6eb035c796a74a540ab1 /mm | |
| parent | 319d1e240683d37924ea8977c91730c3393fd453 (diff) | |
slub: Make the order configurable for each slab cache
Makes /sys/kernel/slab/<slabname>/order writable. The allocation
order of a slab cache can then be changed dynamically during runtime.
This can be used to override the objects per slabs value establisheed
with the slub_min_objects setting that was manually specified or
calculated on bootup.
The changes of the slab order can occur while allocate_slab() runs.
Allocate slab needs the order and the number of slab objects that
are both changed by the change of order. Both are put into
a single word (struct kmem_cache_order_objects). They can then
be atomically updated and retrieved.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slub.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/mm/slub.c b/mm/slub.c index de6f38761d1f..23a2683d6c9f 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -2218,7 +2218,7 @@ static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) * calculate_sizes() determines the order and the distribution of data within * a slab object. */ -static int calculate_sizes(struct kmem_cache *s) +static int calculate_sizes(struct kmem_cache *s, int forced_order) { unsigned long flags = s->flags; unsigned long size = s->objsize; @@ -2307,7 +2307,10 @@ static int calculate_sizes(struct kmem_cache *s) */ size = ALIGN(size, align); s->size = size; - order = calculate_order(size); + if (forced_order >= 0) + order = forced_order; + else + order = calculate_order(size); if (order < 0) return 0; @@ -2346,7 +2349,7 @@ static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, s->align = align; s->flags = kmem_cache_flags(size, flags, name, ctor); - if (!calculate_sizes(s)) + if (!calculate_sizes(s, -1)) goto error; s->refcount = 1; @@ -3833,11 +3836,23 @@ static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) } SLAB_ATTR_RO(objs_per_slab); +static ssize_t order_store(struct kmem_cache *s, + const char *buf, size_t length) +{ + int order = simple_strtoul(buf, NULL, 10); + + if (order > slub_max_order || order < slub_min_order) + return -EINVAL; + + calculate_sizes(s, order); + return length; +} + static ssize_t order_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%d\n", oo_order(s->oo)); } -SLAB_ATTR_RO(order); +SLAB_ATTR(order); static ssize_t ctor_show(struct kmem_cache *s, char *buf) { @@ -3971,7 +3986,7 @@ static ssize_t red_zone_store(struct kmem_cache *s, s->flags &= ~SLAB_RED_ZONE; if (buf[0] == '1') s->flags |= SLAB_RED_ZONE; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(red_zone); @@ -3990,7 +4005,7 @@ static ssize_t poison_store(struct kmem_cache *s, s->flags &= ~SLAB_POISON; if (buf[0] == '1') s->flags |= SLAB_POISON; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(poison); @@ -4009,7 +4024,7 @@ static ssize_t store_user_store(struct kmem_cache *s, s->flags &= ~SLAB_STORE_USER; if (buf[0] == '1') s->flags |= SLAB_STORE_USER; - calculate_sizes(s); + calculate_sizes(s, -1); return length; } SLAB_ATTR(store_user); |