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-rw-r--r--mm/vmalloc.c91
1 files changed, 80 insertions, 11 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6e5a1d263842..c2287313b985 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -509,6 +509,9 @@ static unsigned long lazy_max_pages(void)
static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
+/* for per-CPU blocks */
+static void purge_fragmented_blocks_allcpus(void);
+
/*
* Purges all lazily-freed vmap areas.
*
@@ -539,6 +542,9 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
} else
spin_lock(&purge_lock);
+ if (sync)
+ purge_fragmented_blocks_allcpus();
+
rcu_read_lock();
list_for_each_entry_rcu(va, &vmap_area_list, list) {
if (va->flags & VM_LAZY_FREE) {
@@ -678,6 +684,7 @@ struct vmap_block {
DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS);
struct list_head free_list;
struct rcu_head rcu_head;
+ struct list_head purge;
};
/* Queue of free and dirty vmap blocks, for allocation and flushing purposes */
@@ -782,12 +789,61 @@ static void free_vmap_block(struct vmap_block *vb)
call_rcu(&vb->rcu_head, rcu_free_vb);
}
+static void purge_fragmented_blocks(int cpu)
+{
+ LIST_HEAD(purge);
+ struct vmap_block *vb;
+ struct vmap_block *n_vb;
+ struct vmap_block_queue *vbq = &per_cpu(vmap_block_queue, cpu);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(vb, &vbq->free, free_list) {
+
+ if (!(vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS))
+ continue;
+
+ spin_lock(&vb->lock);
+ if (vb->free + vb->dirty == VMAP_BBMAP_BITS && vb->dirty != VMAP_BBMAP_BITS) {
+ vb->free = 0; /* prevent further allocs after releasing lock */
+ vb->dirty = VMAP_BBMAP_BITS; /* prevent purging it again */
+ bitmap_fill(vb->alloc_map, VMAP_BBMAP_BITS);
+ bitmap_fill(vb->dirty_map, VMAP_BBMAP_BITS);
+ spin_lock(&vbq->lock);
+ list_del_rcu(&vb->free_list);
+ spin_unlock(&vbq->lock);
+ spin_unlock(&vb->lock);
+ list_add_tail(&vb->purge, &purge);
+ } else
+ spin_unlock(&vb->lock);
+ }
+ rcu_read_unlock();
+
+ list_for_each_entry_safe(vb, n_vb, &purge, purge) {
+ list_del(&vb->purge);
+ free_vmap_block(vb);
+ }
+}
+
+static void purge_fragmented_blocks_thiscpu(void)
+{
+ purge_fragmented_blocks(smp_processor_id());
+}
+
+static void purge_fragmented_blocks_allcpus(void)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ purge_fragmented_blocks(cpu);
+}
+
static void *vb_alloc(unsigned long size, gfp_t gfp_mask)
{
struct vmap_block_queue *vbq;
struct vmap_block *vb;
unsigned long addr = 0;
unsigned int order;
+ int purge = 0;
BUG_ON(size & ~PAGE_MASK);
BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC);
@@ -800,24 +856,37 @@ again:
int i;
spin_lock(&vb->lock);
+ if (vb->free < 1UL << order)
+ goto next;
i = bitmap_find_free_region(vb->alloc_map,
VMAP_BBMAP_BITS, order);
- if (i >= 0) {
- addr = vb->va->va_start + (i << PAGE_SHIFT);
- BUG_ON(addr_to_vb_idx(addr) !=
- addr_to_vb_idx(vb->va->va_start));
- vb->free -= 1UL << order;
- if (vb->free == 0) {
- spin_lock(&vbq->lock);
- list_del_rcu(&vb->free_list);
- spin_unlock(&vbq->lock);
+ if (i < 0) {
+ if (vb->free + vb->dirty == VMAP_BBMAP_BITS) {
+ /* fragmented and no outstanding allocations */
+ BUG_ON(vb->dirty != VMAP_BBMAP_BITS);
+ purge = 1;
}
- spin_unlock(&vb->lock);
- break;
+ goto next;
}
+ addr = vb->va->va_start + (i << PAGE_SHIFT);
+ BUG_ON(addr_to_vb_idx(addr) !=
+ addr_to_vb_idx(vb->va->va_start));
+ vb->free -= 1UL << order;
+ if (vb->free == 0) {
+ spin_lock(&vbq->lock);
+ list_del_rcu(&vb->free_list);
+ spin_unlock(&vbq->lock);
+ }
+ spin_unlock(&vb->lock);
+ break;
+next:
spin_unlock(&vb->lock);
}
+
+ if (purge)
+ purge_fragmented_blocks_thiscpu();
+
put_cpu_var(vmap_cpu_blocks);
rcu_read_unlock();