diff options
| -rw-r--r-- | drivers/misc/vmw_balloon.c | 63 |
1 files changed, 52 insertions, 11 deletions
diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c index 4b5e939ff4c8..043eed845246 100644 --- a/drivers/misc/vmw_balloon.c +++ b/drivers/misc/vmw_balloon.c @@ -239,6 +239,7 @@ static DEFINE_STATIC_KEY_FALSE(balloon_stat_enabled); struct vmballoon_ctl { struct list_head pages; struct list_head refused_pages; + struct list_head prealloc_pages; unsigned int n_refused_pages; unsigned int n_pages; enum vmballoon_page_size_type page_size; @@ -668,15 +669,25 @@ static int vmballoon_alloc_page_list(struct vmballoon *b, unsigned int i; for (i = 0; i < req_n_pages; i++) { - if (ctl->page_size == VMW_BALLOON_2M_PAGE) - page = alloc_pages(__GFP_HIGHMEM|__GFP_NOWARN| + /* + * First check if we happen to have pages that were allocated + * before. This happens when 2MB page rejected during inflation + * by the hypervisor, and then split into 4KB pages. + */ + if (!list_empty(&ctl->prealloc_pages)) { + page = list_first_entry(&ctl->prealloc_pages, + struct page, lru); + list_del(&page->lru); + } else { + if (ctl->page_size == VMW_BALLOON_2M_PAGE) + page = alloc_pages(__GFP_HIGHMEM|__GFP_NOWARN| __GFP_NOMEMALLOC, VMW_BALLOON_2M_ORDER); - else - page = balloon_page_alloc(); + else + page = balloon_page_alloc(); - /* Update statistics */ - vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_ALLOC, - ctl->page_size); + vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_ALLOC, + ctl->page_size); + } if (page) { vmballoon_mark_page_offline(page, ctl->page_size); @@ -922,7 +933,8 @@ static void vmballoon_release_page_list(struct list_head *page_list, __free_pages(page, vmballoon_page_order(page_size)); } - *n_pages = 0; + if (n_pages) + *n_pages = 0; } @@ -1055,6 +1067,32 @@ static void vmballoon_dequeue_page_list(struct vmballoon *b, } /** + * vmballoon_split_refused_pages() - Split the 2MB refused pages to 4k. + * + * If inflation of 2MB pages was denied by the hypervisor, it is likely to be + * due to one or few 4KB pages. These 2MB pages may keep being allocated and + * then being refused. To prevent this case, this function splits the refused + * pages into 4KB pages and adds them into @prealloc_pages list. + * + * @ctl: pointer for the %struct vmballoon_ctl, which defines the operation. + */ +static void vmballoon_split_refused_pages(struct vmballoon_ctl *ctl) +{ + struct page *page, *tmp; + unsigned int i, order; + + order = vmballoon_page_order(ctl->page_size); + + list_for_each_entry_safe(page, tmp, &ctl->refused_pages, lru) { + list_del(&page->lru); + split_page(page, order); + for (i = 0; i < (1 << order); i++) + list_add(&page[i].lru, &ctl->prealloc_pages); + } + ctl->n_refused_pages = 0; +} + +/** * vmballoon_inflate() - Inflate the balloon towards its target size. * * @b: pointer to the balloon. @@ -1065,6 +1103,7 @@ static void vmballoon_inflate(struct vmballoon *b) struct vmballoon_ctl ctl = { .pages = LIST_HEAD_INIT(ctl.pages), .refused_pages = LIST_HEAD_INIT(ctl.refused_pages), + .prealloc_pages = LIST_HEAD_INIT(ctl.prealloc_pages), .page_size = b->max_page_size, .op = VMW_BALLOON_INFLATE }; @@ -1112,10 +1151,10 @@ static void vmballoon_inflate(struct vmballoon *b) break; /* - * Ignore errors from locking as we now switch to 4k - * pages and we might get different errors. + * Split the refused pages to 4k. This will also empty + * the refused pages list. */ - vmballoon_release_refused_pages(b, &ctl); + vmballoon_split_refused_pages(&ctl); ctl.page_size--; } @@ -1129,6 +1168,8 @@ static void vmballoon_inflate(struct vmballoon *b) */ if (ctl.n_refused_pages != 0) vmballoon_release_refused_pages(b, &ctl); + + vmballoon_release_page_list(&ctl.prealloc_pages, NULL, ctl.page_size); } /** |