Slab allocators: Replace explicit zeroing with __GFP_ZERO
Christoph Lameter [Tue, 17 Jul 2007 11:03:29 +0000 (04:03 -0700)]
kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing
variant in the past.  But with __GFP_ZERO it is possible now to do zeroing
while allocating.

Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever
we can.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

12 files changed:
block/as-iosched.c
block/cfq-iosched.c
block/deadline-iosched.c
block/elevator.c
block/genhd.c
block/ll_rw_blk.c
drivers/ide/ide-probe.c
kernel/timer.c
lib/genalloc.c
mm/allocpercpu.c
mm/mempool.c
mm/vmalloc.c

index 109e91b..3e316dd 100644 (file)
@@ -1322,10 +1322,9 @@ static void *as_init_queue(request_queue_t *q)
 {
        struct as_data *ad;
 
-       ad = kmalloc_node(sizeof(*ad), GFP_KERNEL, q->node);
+       ad = kmalloc_node(sizeof(*ad), GFP_KERNEL | __GFP_ZERO, q->node);
        if (!ad)
                return NULL;
-       memset(ad, 0, sizeof(*ad));
 
        ad->q = q; /* Identify what queue the data belongs to */
 
index e0aa4da..9755a3c 100644 (file)
@@ -1251,9 +1251,9 @@ cfq_alloc_io_context(struct cfq_data *cfqd, gfp_t gfp_mask)
 {
        struct cfq_io_context *cic;
 
-       cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask, cfqd->queue->node);
+       cic = kmem_cache_alloc_node(cfq_ioc_pool, gfp_mask | __GFP_ZERO,
+                                                       cfqd->queue->node);
        if (cic) {
-               memset(cic, 0, sizeof(*cic));
                cic->last_end_request = jiffies;
                INIT_LIST_HEAD(&cic->queue_list);
                cic->dtor = cfq_free_io_context;
@@ -1376,17 +1376,19 @@ retry:
                         * free memory.
                         */
                        spin_unlock_irq(cfqd->queue->queue_lock);
-                       new_cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask|__GFP_NOFAIL, cfqd->queue->node);
+                       new_cfqq = kmem_cache_alloc_node(cfq_pool,
+                                       gfp_mask | __GFP_NOFAIL | __GFP_ZERO,
+                                       cfqd->queue->node);
                        spin_lock_irq(cfqd->queue->queue_lock);
                        goto retry;
                } else {
-                       cfqq = kmem_cache_alloc_node(cfq_pool, gfp_mask, cfqd->queue->node);
+                       cfqq = kmem_cache_alloc_node(cfq_pool,
+                                       gfp_mask | __GFP_ZERO,
+                                       cfqd->queue->node);
                        if (!cfqq)
                                goto out;
                }
 
-               memset(cfqq, 0, sizeof(*cfqq));
-
                RB_CLEAR_NODE(&cfqq->rb_node);
                INIT_LIST_HEAD(&cfqq->fifo);
 
@@ -2079,12 +2081,10 @@ static void *cfq_init_queue(request_queue_t *q)
 {
        struct cfq_data *cfqd;
 
-       cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL, q->node);
+       cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node);
        if (!cfqd)
                return NULL;
 
-       memset(cfqd, 0, sizeof(*cfqd));
-
        cfqd->service_tree = CFQ_RB_ROOT;
        INIT_LIST_HEAD(&cfqd->cic_list);
 
index 6d673e9..87ca02a 100644 (file)
@@ -360,10 +360,9 @@ static void *deadline_init_queue(request_queue_t *q)
 {
        struct deadline_data *dd;
 
-       dd = kmalloc_node(sizeof(*dd), GFP_KERNEL, q->node);
+       dd = kmalloc_node(sizeof(*dd), GFP_KERNEL | __GFP_ZERO, q->node);
        if (!dd)
                return NULL;
-       memset(dd, 0, sizeof(*dd));
 
        INIT_LIST_HEAD(&dd->fifo_list[READ]);
        INIT_LIST_HEAD(&dd->fifo_list[WRITE]);
index 4769a25..d265963 100644 (file)
@@ -177,11 +177,10 @@ static elevator_t *elevator_alloc(request_queue_t *q, struct elevator_type *e)
        elevator_t *eq;
        int i;
 
-       eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL, q->node);
+       eq = kmalloc_node(sizeof(elevator_t), GFP_KERNEL | __GFP_ZERO, q->node);
        if (unlikely(!eq))
                goto err;
 
-       memset(eq, 0, sizeof(*eq));
        eq->ops = &e->ops;
        eq->elevator_type = e;
        kobject_init(&eq->kobj);
index 863a8c0..b321cad 100644 (file)
@@ -726,21 +726,21 @@ struct gendisk *alloc_disk_node(int minors, int node_id)
 {
        struct gendisk *disk;
 
-       disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
+       disk = kmalloc_node(sizeof(struct gendisk),
+                               GFP_KERNEL | __GFP_ZERO, node_id);
        if (disk) {
-               memset(disk, 0, sizeof(struct gendisk));
                if (!init_disk_stats(disk)) {
                        kfree(disk);
                        return NULL;
                }
                if (minors > 1) {
                        int size = (minors - 1) * sizeof(struct hd_struct *);
-                       disk->part = kmalloc_node(size, GFP_KERNEL, node_id);
+                       disk->part = kmalloc_node(size,
+                               GFP_KERNEL | __GFP_ZERO, node_id);
                        if (!disk->part) {
                                kfree(disk);
                                return NULL;
                        }
-                       memset(disk->part, 0, size);
                }
                disk->minors = minors;
                kobj_set_kset_s(disk,block_subsys);
index 11e4235..d7cadf3 100644 (file)
@@ -1829,11 +1829,11 @@ request_queue_t *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 {
        request_queue_t *q;
 
-       q = kmem_cache_alloc_node(requestq_cachep, gfp_mask, node_id);
+       q = kmem_cache_alloc_node(requestq_cachep,
+                               gfp_mask | __GFP_ZERO, node_id);
        if (!q)
                return NULL;
 
-       memset(q, 0, sizeof(*q));
        init_timer(&q->unplug_timer);
 
        snprintf(q->kobj.name, KOBJ_NAME_LEN, "%s", "queue");
index cc58013..5a4c5ea 100644 (file)
@@ -1073,14 +1073,14 @@ static int init_irq (ide_hwif_t *hwif)
                hwgroup->hwif->next = hwif;
                spin_unlock_irq(&ide_lock);
        } else {
-               hwgroup = kmalloc_node(sizeof(ide_hwgroup_t), GFP_KERNEL,
+               hwgroup = kmalloc_node(sizeof(ide_hwgroup_t),
+                                       GFP_KERNEL | __GFP_ZERO,
                                        hwif_to_node(hwif->drives[0].hwif));
                if (!hwgroup)
                        goto out_up;
 
                hwif->hwgroup = hwgroup;
 
-               memset(hwgroup, 0, sizeof(ide_hwgroup_t));
                hwgroup->hwif     = hwif->next = hwif;
                hwgroup->rq       = NULL;
                hwgroup->handler  = NULL;
index 1258371..b7792fb 100644 (file)
@@ -1221,7 +1221,8 @@ static int __devinit init_timers_cpu(int cpu)
                        /*
                         * The APs use this path later in boot
                         */
-                       base = kmalloc_node(sizeof(*base), GFP_KERNEL,
+                       base = kmalloc_node(sizeof(*base),
+                                               GFP_KERNEL | __GFP_ZERO,
                                                cpu_to_node(cpu));
                        if (!base)
                                return -ENOMEM;
@@ -1232,7 +1233,6 @@ static int __devinit init_timers_cpu(int cpu)
                                kfree(base);
                                return -ENOMEM;
                        }
-                       memset(base, 0, sizeof(*base));
                        per_cpu(tvec_bases, cpu) = base;
                } else {
                        /*
index eb7c2ba..f6d276d 100644 (file)
@@ -54,11 +54,10 @@ int gen_pool_add(struct gen_pool *pool, unsigned long addr, size_t size,
        int nbytes = sizeof(struct gen_pool_chunk) +
                                (nbits + BITS_PER_BYTE - 1) / BITS_PER_BYTE;
 
-       chunk = kmalloc_node(nbytes, GFP_KERNEL, nid);
+       chunk = kmalloc_node(nbytes, GFP_KERNEL | __GFP_ZERO, nid);
        if (unlikely(chunk == NULL))
                return -1;
 
-       memset(chunk, 0, nbytes);
        spin_lock_init(&chunk->lock);
        chunk->start_addr = addr;
        chunk->end_addr = addr + size;
index b2486cf..00b0262 100644 (file)
@@ -53,12 +53,9 @@ void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu)
        int node = cpu_to_node(cpu);
 
        BUG_ON(pdata->ptrs[cpu]);
-       if (node_online(node)) {
-               /* FIXME: kzalloc_node(size, gfp, node) */
-               pdata->ptrs[cpu] = kmalloc_node(size, gfp, node);
-               if (pdata->ptrs[cpu])
-                       memset(pdata->ptrs[cpu], 0, size);
-       } else
+       if (node_online(node))
+               pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node);
+       else
                pdata->ptrs[cpu] = kzalloc(size, gfp);
        return pdata->ptrs[cpu];
 }
index 3e8f1fe..02d5ec3 100644 (file)
@@ -62,10 +62,9 @@ mempool_t *mempool_create_node(int min_nr, mempool_alloc_t *alloc_fn,
                        mempool_free_t *free_fn, void *pool_data, int node_id)
 {
        mempool_t *pool;
-       pool = kmalloc_node(sizeof(*pool), GFP_KERNEL, node_id);
+       pool = kmalloc_node(sizeof(*pool), GFP_KERNEL | __GFP_ZERO, node_id);
        if (!pool)
                return NULL;
-       memset(pool, 0, sizeof(*pool));
        pool->elements = kmalloc_node(min_nr * sizeof(void *),
                                        GFP_KERNEL, node_id);
        if (!pool->elements) {
index ddf8714..8e05a11 100644 (file)
@@ -432,11 +432,12 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
        area->nr_pages = nr_pages;
        /* Please note that the recursion is strictly bounded. */
        if (array_size > PAGE_SIZE) {
-               pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node);
+               pages = __vmalloc_node(array_size, gfp_mask | __GFP_ZERO,
+                                       PAGE_KERNEL, node);
                area->flags |= VM_VPAGES;
        } else {
                pages = kmalloc_node(array_size,
-                               (gfp_mask & GFP_LEVEL_MASK),
+                               (gfp_mask & GFP_LEVEL_MASK) | __GFP_ZERO,
                                node);
        }
        area->pages = pages;
@@ -445,7 +446,6 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
                kfree(area);
                return NULL;
        }
-       memset(area->pages, 0, array_size);
 
        for (i = 0; i < area->nr_pages; i++) {
                if (node < 0)