From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Lameter Subject: [patch 09/23] SLUB: Add get() and kick() methods Date: Tue, 06 Nov 2007 17:11:39 -0800 Message-ID: <20071107011228.605750914@sgi.com> References: <20071107011130.382244340@sgi.com> Return-path: Content-Disposition: inline; filename=0006-slab_defrag_get_and_kick_method.patch Sender: linux-kernel-owner@vger.kernel.org To: akpm@linux-foundatin.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Mel Gorman List-Id: linux-mm.kvack.org Add the two methods needed for defragmentation and add the display of the methods via the proc interface. Add documentation explaining the use of these methods. Reviewed-by: Rik van Riel Signed-off-by: Christoph Lameter --- include/linux/slab.h | 3 +++ include/linux/slub_def.h | 31 +++++++++++++++++++++++++++++++ mm/slub.c | 32 ++++++++++++++++++++++++++++++-- 3 files changed, 64 insertions(+), 2 deletions(-) Index: linux-2.6/include/linux/slab.h =================================================================== --- linux-2.6.orig/include/linux/slab.h 2007-10-17 13:35:53.000000000 -0700 +++ linux-2.6/include/linux/slab.h 2007-11-06 12:37:51.000000000 -0800 @@ -56,6 +56,9 @@ struct kmem_cache *kmem_cache_create(con void (*)(struct kmem_cache *, void *)); void kmem_cache_destroy(struct kmem_cache *); int kmem_cache_shrink(struct kmem_cache *); +void kmem_cache_setup_defrag(struct kmem_cache *s, + void *(*get)(struct kmem_cache *, int nr, void **), + void (*kick)(struct kmem_cache *, int nr, void **, void *private)); void kmem_cache_free(struct kmem_cache *, void *); unsigned int kmem_cache_size(struct kmem_cache *); const char *kmem_cache_name(struct kmem_cache *); Index: linux-2.6/include/linux/slub_def.h =================================================================== --- linux-2.6.orig/include/linux/slub_def.h 2007-11-06 12:37:44.000000000 -0800 +++ linux-2.6/include/linux/slub_def.h 2007-11-06 12:37:51.000000000 -0800 @@ -51,6 +51,37 @@ struct kmem_cache { int objects; /* Number of objects in slab */ int refcount; /* Refcount for slab cache destroy */ void (*ctor)(struct kmem_cache *, void *); + /* + * Called with slab lock held and interrupts disabled. + * No slab operation may be performed in get(). + * + * Parameters passed are the number of objects to process + * and an array of pointers to objects for which we + * need references. + * + * Returns a pointer that is passed to the kick function. + * If all objects cannot be moved then the pointer may + * indicate that this wont work and then kick can simply + * remove the references that were already obtained. + * + * The array passed to get() is also passed to kick(). The + * function may remove objects by setting array elements to NULL. + */ + void *(*get)(struct kmem_cache *, int nr, void **); + + /* + * Called with no locks held and interrupts enabled. + * Any operation may be performed in kick(). + * + * Parameters passed are the number of objects in the array, + * the array of pointers to the objects and the pointer + * returned by get(). + * + * Success is checked by examining the number of remaining + * objects in the slab. + */ + void (*kick)(struct kmem_cache *, int nr, void **, void *private); + int inuse; /* Offset to metadata */ int align; /* Alignment */ int defrag_ratio; /* Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c 2007-11-06 12:37:47.000000000 -0800 +++ linux-2.6/mm/slub.c 2007-11-06 12:37:51.000000000 -0800 @@ -2760,6 +2760,20 @@ void kfree(const void *x) } EXPORT_SYMBOL(kfree); +void kmem_cache_setup_defrag(struct kmem_cache *s, + void *(*get)(struct kmem_cache *, int nr, void **), + void (*kick)(struct kmem_cache *, int nr, void **, void *private)) +{ + /* + * Defragmentable slabs must have a ctor otherwise objects may be + * in an undetermined state after they are allocated. + */ + BUG_ON(!s->ctor); + s->get = get; + s->kick = kick; +} +EXPORT_SYMBOL(kmem_cache_setup_defrag); + static unsigned long count_partial(struct kmem_cache_node *n) { unsigned long flags; @@ -3058,7 +3072,7 @@ static int slab_unmergeable(struct kmem_ if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE)) return 1; - if (s->ctor) + if (s->ctor || s->kick || s->get) return 1; /* @@ -3795,7 +3809,21 @@ static ssize_t ops_show(struct kmem_cach if (s->ctor) { x += sprintf(buf + x, "ctor : "); - x += sprint_symbol(buf + x, (unsigned long)s->ops->ctor); + x += sprint_symbol(buf + x, (unsigned long)s->ctor); + x += sprintf(buf + x, "\n"); + } + + if (s->get) { + x += sprintf(buf + x, "get : "); + x += sprint_symbol(buf + x, + (unsigned long)s->get); + x += sprintf(buf + x, "\n"); + } + + if (s->kick) { + x += sprintf(buf + x, "kick : "); + x += sprint_symbol(buf + x, + (unsigned long)s->kick); x += sprintf(buf + x, "\n"); } return x; --