[PATCH 33/49] vmalloc

[Chris Wilson]

---
 mm/vmalloc.c | 29 +++++++----------------------
 1 file changed, 7 insertions(+), 22 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 7e945c63c7ef..d4d6b70d34eb 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -44,6 +44,8 @@ struct vfree_deferred {
 };
 static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
 
+static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
+
 static void __vunmap(const void *, int);
 
 static void free_work(struct work_struct *w)
@@ -319,7 +321,6 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 	struct vmap_area *va;
 	struct rb_node *n;
 	unsigned long addr;
-	int purged = 0;
 	struct vmap_area *first;
 
 	BUG_ON(!size);
@@ -428,19 +429,16 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 
 overflow:
 	spin_unlock(&vmap_area_lock);
-	if (!purged) {
+	if (atomic_read(&vmap_lazy_nr) > (size >> PAGE_SHIFT)) {
 		purge_vmap_area_lazy();
-		purged = 1;
 		goto retry;
 	}
 
 	if (gfpflags_allow_blocking(gfp_mask)) {
 		unsigned long freed = 0;
 		blocking_notifier_call_chain(&vmap_notify_list, 0, &freed);
-		if (freed > 0) {
-			purged = 0;
+		if (freed > 0)
 			goto retry;
-		}
 	}
 
 	if (printk_ratelimit())
@@ -560,8 +558,6 @@ static unsigned long lazy_max_pages(void)
 	return log * (32UL * 1024 * 1024 / PAGE_SIZE);
 }
 
-static atomic_t vmap_lazy_nr = ATOMIC_INIT(0);
-
 /* for per-CPU blocks */
 static void purge_fragmented_blocks_allcpus(void);
 
@@ -587,7 +583,6 @@ void set_iounmap_nonlazy(void)
 static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 					int sync, int force_flush)
 {
-	static DEFINE_SPINLOCK(purge_lock);
 	struct llist_node *valist;
 	struct vmap_area *va;
 	struct vmap_area *n_va;
@@ -598,12 +593,6 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 	 * should not expect such behaviour. This just simplifies locking for
 	 * the case that isn't actually used at the moment anyway.
 	 */
-	if (!sync && !force_flush) {
-		if (!spin_trylock(&purge_lock))
-			return;
-	} else
-		spin_lock(&purge_lock);
-
 	if (sync)
 		purge_fragmented_blocks_allcpus();
 
@@ -616,9 +605,6 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 		nr += (va->va_end - va->va_start) >> PAGE_SHIFT;
 	}
 
-	if (nr)
-		atomic_sub(nr, &vmap_lazy_nr);
-
 	if (nr || force_flush)
 		flush_tlb_kernel_range(*start, *end);
 
@@ -627,8 +613,9 @@ static void __purge_vmap_area_lazy(unsigned long *start, unsigned long *end,
 		llist_for_each_entry_safe(va, n_va, valist, purge_list)
 			__free_vmap_area(va);
 		spin_unlock(&vmap_area_lock);
+
+		atomic_sub(nr, &vmap_lazy_nr);
 	}
-	spin_unlock(&purge_lock);
 }
 
 /*
@@ -2370,7 +2357,6 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 	struct vm_struct **vms;
 	int area, area2, last_area, term_area;
 	unsigned long base, start, end, last_end;
-	bool purged = false;
 
 	/* verify parameters and allocate data structures */
 	BUG_ON(offset_in_page(align) || !is_power_of_2(align));
@@ -2439,9 +2425,8 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 		 */
 		if (base + last_end < vmalloc_start + last_end) {
 			spin_unlock(&vmap_area_lock);
-			if (!purged) {
+			if (atomic_read(&vmap_lazy_nr)) {
 				purge_vmap_area_lazy();
-				purged = true;
 				goto retry;
 			}
 			goto err_free;
-- 
2.10.2