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Diffstat (limited to 'mm/vmalloc.c')
-rw-r--r--mm/vmalloc.c114
1 files changed, 87 insertions, 27 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 37e69295f25..ae007462b7f 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) {
@@ -555,10 +561,8 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
}
rcu_read_unlock();
- if (nr) {
- BUG_ON(nr > atomic_read(&vmap_lazy_nr));
+ if (nr)
atomic_sub(nr, &vmap_lazy_nr);
- }
if (nr || force_flush)
flush_tlb_kernel_range(*start, *end);
@@ -669,8 +673,6 @@ static bool vmap_initialized __read_mostly = false;
struct vmap_block_queue {
spinlock_t lock;
struct list_head free;
- struct list_head dirty;
- unsigned int nr_dirty;
};
struct vmap_block {
@@ -680,10 +682,9 @@ struct vmap_block {
unsigned long free, dirty;
DECLARE_BITMAP(alloc_map, VMAP_BBMAP_BITS);
DECLARE_BITMAP(dirty_map, VMAP_BBMAP_BITS);
- union {
- struct list_head free_list;
- struct rcu_head rcu_head;
- };
+ 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 */
@@ -759,7 +760,7 @@ static struct vmap_block *new_vmap_block(gfp_t gfp_mask)
vbq = &get_cpu_var(vmap_block_queue);
vb->vbq = vbq;
spin_lock(&vbq->lock);
- list_add(&vb->free_list, &vbq->free);
+ list_add_rcu(&vb->free_list, &vbq->free);
spin_unlock(&vbq->lock);
put_cpu_var(vmap_block_queue);
@@ -778,8 +779,6 @@ static void free_vmap_block(struct vmap_block *vb)
struct vmap_block *tmp;
unsigned long vb_idx;
- BUG_ON(!list_empty(&vb->free_list));
-
vb_idx = addr_to_vb_idx(vb->va->va_start);
spin_lock(&vmap_block_tree_lock);
tmp = radix_tree_delete(&vmap_block_tree, vb_idx);
@@ -790,12 +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);
@@ -808,24 +856,38 @@ 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_init(&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_block_queue);
rcu_read_unlock();
@@ -862,11 +924,11 @@ static void vb_free(const void *addr, unsigned long size)
BUG_ON(!vb);
spin_lock(&vb->lock);
- bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order);
+ BUG_ON(bitmap_allocate_region(vb->dirty_map, offset >> PAGE_SHIFT, order));
vb->dirty += 1UL << order;
if (vb->dirty == VMAP_BBMAP_BITS) {
- BUG_ON(vb->free || !list_empty(&vb->free_list));
+ BUG_ON(vb->free);
spin_unlock(&vb->lock);
free_vmap_block(vb);
} else
@@ -1035,8 +1097,6 @@ void __init vmalloc_init(void)
vbq = &per_cpu(vmap_block_queue, i);
spin_lock_init(&vbq->lock);
INIT_LIST_HEAD(&vbq->free);
- INIT_LIST_HEAD(&vbq->dirty);
- vbq->nr_dirty = 0;
}
/* Import existing vmlist entries. */
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-03 11:57:40 +0000