vmware balloon: clamp number of collected non-balloonable pages

[pandora-kernel.git] / drivers / misc / vmware_balloon.c

diff --git a/drivers/misc/vmware_balloon.c b/drivers/misc/vmware_balloon.c
index db9cd02..2a1e804 100644 (file)
--- a/drivers/misc/vmware_balloon.c
+++ b/drivers/misc/vmware_balloon.c
@@ -45,7 +45,7 @@
 
 MODULE_AUTHOR("VMware, Inc.");
 MODULE_DESCRIPTION("VMware Memory Control (Balloon) Driver");
-MODULE_VERSION("1.2.1.0-K");
+MODULE_VERSION("1.2.1.1-k");
 MODULE_ALIAS("dmi:*:svnVMware*:*");
 MODULE_ALIAS("vmware_vmmemctl");
 MODULE_LICENSE("GPL");
@@ -101,6 +101,8 @@ MODULE_LICENSE("GPL");
 /* Maximum number of page allocations without yielding processor */
 #define VMW_BALLOON_YIELD_THRESHOLD    1024
 
+/* Maximum number of refused pages we accumulate during inflation cycle */
+#define VMW_BALLOON_MAX_REFUSED                16
 
 /*
  * Hypervisor communication port definitions.
@@ -183,6 +185,7 @@ struct vmballoon {
 
        /* transient list of non-balloonable pages */
        struct list_head refused_pages;
+       unsigned int n_refused_pages;
 
        /* balloon size in pages */
        unsigned int size;
@@ -428,14 +431,21 @@ static int vmballoon_reserve_page(struct vmballoon *b, bool can_sleep)
                /* inform monitor */
                locked = vmballoon_send_lock_page(b, page_to_pfn(page));
                if (!locked) {
+                       STATS_INC(b->stats.refused_alloc);
+
                        if (b->reset_required) {
                                __free_page(page);
                                return -EIO;
                        }
 
-                       /* place on list of non-balloonable pages, retry allocation */
+                       /*
+                        * Place page on the list of non-balloonable pages
+                        * and retry allocation, unless we already accumulated
+                        * too many of them, in which case take a breather.
+                        */
                        list_add(&page->lru, &b->refused_pages);
-                       STATS_INC(b->stats.refused_alloc);
+                       if (++b->n_refused_pages >= VMW_BALLOON_MAX_REFUSED)
+                               return -EIO;
                }
        } while (!locked);
 
@@ -483,6 +493,8 @@ static void vmballoon_release_refused_pages(struct vmballoon *b)
                __free_page(page);
                STATS_INC(b->stats.refused_free);
        }
+
+       b->n_refused_pages = 0;
 }
 
 /*