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authorUladzislau Rezki <urezki@gmail.com>2021-06-28 19:40:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-06-29 10:53:52 -0700
commit12b9f873a5d0e6b3846835ec973bbafa338d0b5a (patch)
treec5617fa2f576635dabe193530fb9debc3c202cb4 /mm/vmalloc.c
parentf4bdfeaf18a44b4d0bca945ace272cbf5e91a1b3 (diff)
mm/vmalloc: fallback to a single page allocator
Currently for order-0 pages we use a bulk-page allocator to get set of pages. From the other hand not allocating all pages is something that might occur. In that case we should fallbak to the single-page allocator trying to get missing pages, because it is more permissive(direct reclaim, etc). Introduce a vm_area_alloc_pages() function where the described logic is implemented. Link: https://lkml.kernel.org/r/20210521130718.GA17882@pc638.lan Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Mel Gorman <mgorman@suse.de> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/vmalloc.c')
-rw-r--r--mm/vmalloc.c81
1 files changed, 52 insertions, 29 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ed0a32ea09ee..0c80caaf041a 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2758,6 +2758,54 @@ void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot)
EXPORT_SYMBOL_GPL(vmap_pfn);
#endif /* CONFIG_VMAP_PFN */
+static inline unsigned int
+vm_area_alloc_pages(gfp_t gfp, int nid,
+ unsigned int order, unsigned long nr_pages, struct page **pages)
+{
+ unsigned int nr_allocated = 0;
+
+ /*
+ * For order-0 pages we make use of bulk allocator, if
+ * the page array is partly or not at all populated due
+ * to fails, fallback to a single page allocator that is
+ * more permissive.
+ */
+ if (!order)
+ nr_allocated = alloc_pages_bulk_array_node(
+ gfp, nid, nr_pages, pages);
+ else
+ /*
+ * Compound pages required for remap_vmalloc_page if
+ * high-order pages.
+ */
+ gfp |= __GFP_COMP;
+
+ /* High-order pages or fallback path if "bulk" fails. */
+ while (nr_allocated < nr_pages) {
+ struct page *page;
+ int i;
+
+ page = alloc_pages_node(nid, gfp, order);
+ if (unlikely(!page))
+ break;
+
+ /*
+ * Careful, we allocate and map page-order pages, but
+ * tracking is done per PAGE_SIZE page so as to keep the
+ * vm_struct APIs independent of the physical/mapped size.
+ */
+ for (i = 0; i < (1U << order); i++)
+ pages[nr_allocated + i] = page + i;
+
+ if (gfpflags_allow_blocking(gfp))
+ cond_resched();
+
+ nr_allocated += 1U << order;
+ }
+
+ return nr_allocated;
+}
+
static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
pgprot_t prot, unsigned int page_shift,
int node)
@@ -2790,37 +2838,11 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
return NULL;
}
- area->nr_pages = 0;
set_vm_area_page_order(area, page_shift - PAGE_SHIFT);
page_order = vm_area_page_order(area);
- if (!page_order) {
- area->nr_pages = alloc_pages_bulk_array_node(
- gfp_mask, node, nr_small_pages, area->pages);
- } else {
- /*
- * Careful, we allocate and map page_order pages, but tracking is done
- * per PAGE_SIZE page so as to keep the vm_struct APIs independent of
- * the physical/mapped size.
- */
- while (area->nr_pages < nr_small_pages) {
- struct page *page;
- int i;
-
- /* Compound pages required for remap_vmalloc_page */
- page = alloc_pages_node(node, gfp_mask | __GFP_COMP, page_order);
- if (unlikely(!page))
- break;
-
- for (i = 0; i < (1U << page_order); i++)
- area->pages[area->nr_pages + i] = page + i;
-
- if (gfpflags_allow_blocking(gfp_mask))
- cond_resched();
-
- area->nr_pages += 1U << page_order;
- }
- }
+ area->nr_pages = vm_area_alloc_pages(gfp_mask, node,
+ page_order, nr_small_pages, area->pages);
atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
@@ -2835,7 +2857,8 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
goto fail;
}
- if (vmap_pages_range(addr, addr + size, prot, area->pages, page_shift) < 0) {
+ if (vmap_pages_range(addr, addr + size, prot, area->pages,
+ page_shift) < 0) {
warn_alloc(gfp_mask, NULL,
"vmalloc error: size %lu, failed to map pages",
area->nr_pages * PAGE_SIZE);